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The Regulatory Reform (Fire Safety) Order 2005 came into effect on 1 st October 2006 and reforms several pieces of legislation concerned with fire safety including Fire Precautions Act 1971 and the Fire Precautions (Workplace) Regulations 1997. To enable business to comply, a number of documents where produced. Guide 1 – Offices and Shops, Guide 2 – Factories and Warehouses, Guide 3 – Sleeping Accommodation, Guide 4 – Residential Care Premises, Guide 5 – Educational Premises, Guide 6 – Small and Medium places of assembly, Guide 7 – Large places of assembly – Guide 8 -Theatres and Cinemas, Guide 9 – Outdoor events, Guide 10 – Healthcare Premises, Guide 11 – Transport premises and facilities. The Regulatory Reform (Fire Safety) Order 2005 comprises of five parts: General Application, Fire Safety Duties, Enforcement, Offences and Appeals, Miscellaneous Part 1 – Application. The order applies to all non domestic premises (with exceptions listed in article 6 such as ships, offshore, aircraft), and includes advice in four parts (in schedule 1): • The matters to be considered in risk assessment for dangerous substances. • The matters to be taken into account in risk assessment for young children. • Principles of prevention (hierarchy of control) • Measures to be taken in respect of dangerous substances. A number of definitions in part 1 include: • Responsible Person, which could be considered as: The employer with control of the workplace, person with overall management of the building, occupier of the premises, owner of the premises. • General Fire Precautions – Measures to reduce the risk and spread of fire, means of escape that can be safely and effectively used at all times, means of lighting fire, means for detecting fire and giving warning in case of fire, arrangements for action to be taken in the event of fire, including instruction and training of employees, and measure to mitigate effects of fire. Part 2 – Fire Safety Duties A duty is placed on the responsible person for to take reasonable precautions to ensure SFARP the safety of the persons they employ. This is also the case for those not in their employment such as visitors, contractors and fire fighters. Risk Assessment – The responsible person should carry out a suitable and sufficient risk assessment or nominate a person to do this on their behalf. No new work activity should start that involves dangerous substances unless a risk assessment has been done and any measures implemented. Risk assessments should be reviewed if they are no longer valid, or significant changes have occurred. If there are five or more persons working on the premises, the risk assessment must be recorded. No young person to be employed unless a risk assessment has been carried out in relation to risks to young people. Principles of Prevention to be applied (specified in Part 3, Schedule 1). • Avoiding the risks • Evaluating the risks that cannot be avoided • Combating the risks at source • Adapting to technical progress • Replacing the dangerous by the non or less dangerous. • Develop a coherent overall prevention policy which covers technology, organisation of work and the influence of factors relating to the working environment. • Giving collective measures priority over individual measures. • Giving appropriate instructions to people. Fire Safety Arrangements Employers must implement arrangements for the effective planning, organisation, control, monitoring and review identified by the risk assessment.
Regulatory Reform (Fire Safety) Order 2005 – Part 1 Regulatory Reform (Fire Safety) Order 2005 – Part 2
Elimination of the risks from dangerous substances. • Reduce quantity to a minimum • Avoid or minimise the release of a dangerous substance • Control the release at source • Prevent the formation of explosive atmosphere (appropriate ventilation etc) • Ensure any release which may at a risk is suitably contained and collected and rendered safe. • Avoided. • Ignition sources including electrostatic discharges. • Other adverse conditions such as could result in harmful effects. • Segregate incompatible substances. Mitigation Measures • Reduce number of persons exposed • Measures to avoid propagation of fires and explosions • Providing explosive pressure relief arrangements • Providing explosion suppression equipment • Providing plant which is constructed to withstand explosion • Providing suitable PPE. Arrangements need to be in place for safe handling, storage and transport and any risks are eliminated and controlled. Emergency Routes and Exits These should be kept clear at all times and in addition. • Routes and exits must lead as directly as possible to a place of safety • It must be possible to evacuate as quickly as possible • Numbers, dimensions and distribution must be adequate in regard to use, maximum persons present and equipment within the premises. • Emergency doors must open in the direction of travel. Sliding or revolving doors must not be used as specific emergency exits. • To be indicated by appropriate signage. • Where lighting is required, this must be emergency light of adequate intensity. The employer has a duty to put into place procedures that will cover drills, nominated person to aid evacuation and ensure access to danger areas is restricted to those who are trained. Additional measures in response of dangerous occurrences: • Information on emergency arrangements is available. • Suitable warning and communication methods are available for immediate response and rescue. • Visible and audible warning signs are given and persons are withdrawn before any explosive conditions are reached. • Escape facilities are provided and maintained. • Information is available to the emergency services on procedures, arrangements and hazards. Maintenance All equipment, facilities and devices are to be maintained in a good state, working order and repair. Information to Employees Information should be provided such as risks they may be exposed to, preventative measures in place, procedures for emergency arrangements and who the competent persons are. Training Employees should have adequate training with regards to Fire Safety on induction and when there are new circumstance that warrant a refresher and should be repeated periodically. Coordination and Cooperation Where there is more than one employer occupying a building, they should seek to cooperate and coordinate with each other. Duties of Employees These duties are similar to section 7 of the HASWA and Regulation 14 of MHSWR. Part 3 – Enforcement For most premises, the enforcing authority will be the fire authority for the area. Some exceptions to these are: Licensed nuclear sites, ships, construction sites which are managed by the HSE. The fire service maintained by the secretary of state for defence for premises solely occupied by armed forces. Fire Inspectors authorised by the secretary of state for crown premises. Article 27 of the order covers the powers of inspectors and sets out general power to ‘do anything for the purpose of carrying out the order’. Specific powers include: • Ascertain if the order applies. • Identify responsible person. • Take samples of articles and substances to ascertain fire resistance or flammability. • Enter premises at a reasonable time. • Inspect and take copies of records. • Other powers similar to section 20 of the act.
Regulatory Reform (Fire Safety) Order 2005 – Part 2 Regulatory Reform (Fire Safety) Order 2005 – Part 3 Regulatory Reform (Fire Safety) Order 2005 – Part 2
Successful Fire Safety Management Part 3 – Cont’d In addition part 3 details the different notices that can be served. These are: • Alterations Notice – served if there is believed to be a serious risk to persons should the premises be changed in relation to its structure or change of use. The responsible person must then inform the authority before making any changes with a copy of the risk assessment and proposed changes. • Enforcement Notice – issued when it is believed the responsible person had failed to comply with any of the requirements set out in the order. The then have to remedy the issues within a given time frame, which should not be less than 28 days. The notice will detail what is not compliant and may put measures that could be considered. • Prohibition Notice – Issued if there is believed to be a serious risk. This would normally take effect immediately and have remedial action that should be taken. Being served with the notice is not an offence, but failure to comply with the notice is an offence. Part 4 – Offences and Appeals This gives details of appeals that can be made. Appeals should be made within 21 days of the notice being served. The RRFSO imposes a duty on the responsible person to have fire arrangements in place. The arrangements should consider the need for a policy, organisational responsibilities, effective planned, implementation, monitoring, audit and review. Policy – This should detail who has overall responsibility, Organisation - This should detail general arrangements and responsibilities such as who fire wardens and assessors are. The competence levels should be defined to undertake certain roles and also how it communicates its fire safety arrangements out to the workforce. This should also include consultation with employees on fire safety matters. Planning and Implementation - Essential to implement fire safety policies and procedures, and should include: • Identification of fire hazards in the workplace • Evaluate the risks that could be realized • Putting together an action plan based on the findings of the risk assessment. • Development of procedures for fire fighting. • Arrangements for the control of dangerous substances. • Maintenance arrangements for protective measures. • Written fire instructions / training requirements • Measures for control and cooperation of occupants • System for recording fire incidents / fire drills. Monitoring and Review - This is done to ensure a company is complying with requirements. It should use proactive and reactive techniques. The reviews should be regular, and allow for changes to the company. Auditing – This will involve a systematic evaluation of the whole management system for fire and check levels of compliance with its own and external standards. For alternation and enforcement notices, the notice may be suspended until the hearing , whereas a prohibition notice will remain in place. Post Fire Management Failure to comply with a notice can lead to a summary conviction. This is a maximum fine of £ 5, 000. On indictment, this could lead to an unlimited fine. Investigating fires – the purpose of investigating the fire may depend on who is investigating. Internal investigations may seek to find the cause of the fire and also to see how it can be prevented from occurring again. It may be for gathering evidence for civil claims, or to defend any potential criminal proceedings that could arise. Where a company is prosecuted for failure to comply with any provisions of the order the penalties include a summary conviction, maximum fine of £ 5, 00, and on indictment, this can be an unlimited fine and up to 2 years in prison. Normally these are heard in a magistrates court unless deemed more serious and then would be heard in the crown court. External investigations may include those from the fire and rescue service to determine cause, gather evidence and potentially bring criminal proceedings. Insurance companies may want to investigate to allow them to defend any liabilities. The police may be involved if there is a suspected crime such as fraud or arson. Forensic science may be involved in suspected cases of arson or where they have been fatalities. The HSE may investigate if the fire is reported under RIDDOR. Other parties may include the environment agency or utilities.
Regulatory Reform (Fire Safety) Order 2005 – Part 4 Successful Fire Safety Management Regulatory Reform (Fire Safety) Order 2005 – Part 3 Successful Fire Safety Management
Fire Investigation Procedure A fire investigation may start even before the fire has been completely extinguished if it means evidence collecting can begin where putting out the fire may lead to the crime scene being destroyed. It is important to preserve as much of the scene as possible to allow for this. Fires will be classes as either: Accidental - This is where a fire is not suspected as arson but by some other means. The fire and rescue authority would use the powers it has under the fire and rescue act to investigate and pursue criminal action is there has been a breach in legislation. Arson Set Fires - Arson is investigated by the fire and rescue service to assist the police in bringing those who started the fire to court. False alarms may also be investigated to determine the cause of the alarm and where this is excessive further action may be taken such as a reduction in the level of response a company may receive. Reporting and Recording of Fire Incidents Statutory Reporting. The responsible person may need to inform the statutory body (i. e. the HSE when it is reportable under RIDDOR). The following incidents must be reported in connection with work: • Death of any person (reported by the quickest practical means, followed within 10 days of F 2508). • Major Injuries to any person at work (reported by the quickest practical means, followed within 10 days by F 2508). • Incapacity of a person at work for more than 7 days (reported within 10 days on form F 2508). • Dangerous Occurrence. The different types reportable are: • Electrical short circuit or overload causing fire or explosion. • Explosion, collapse or bursting of any closed vessel or associated pipework. • Road tanker carrying a dangerous substance overturns, suffers serious damage, catches fire, or the substance is released. • Dangerous substance conveyed by road is involved in a fire. • Explosion or fire resulting in suspension of normal work for more than 24 hours. Recording Of Incidents If an injury occurs as a result of a fire, this should be recorded in the accident book. Fire log books can also be used to record incidents of a similar nature. Element 2 – Principles of Fire and Explosion Fire Investigation Procedure - Continued Combustion Process. The process of gathering evidence will include: • Physical evidence such as photos, diagrams, CCTV • Observational evidence from eye witnesses and those who raised the alarm. • Documentary evidence such as plans, risk assessments, procedures etc • Locating the seat of the fire which may require specialist knowledge. • Excavating the seat of the fire to determine the origin. Once gathered and evaluated, the extent of the losses can be established and cause identified. Once the cause has been established, preventative measures can be put in place. A full report should then be prepared and given to all relevant parties. Once all of the above has been completed, then the site cleanup can begin and health & safety must be considered when doing so, as specialist services may be required. Combustion is a chemical reaction and this reaction can give off heat, light, smoke or flames.
Fire Investigation Procedure Continued Principles of Fire and Explosion Fire Investigation Procedure Reporting and Recording of Fire Incidents
Classification of Fires Factors influencing fire growth Several factors influence the growth rate of a fire: • The amount of oxygen available will be considerably enhance growth, This can be when windows are left open, or mechanical systems are left running. • The amount of vapour released will affect growth rate. This is dependant on the type and size of the material and also the temperature to which it is being exposed. Petrol for example will easily ignite, whereas wood will not. • Method and style of construction of a building – buildings that are open plan or have large open spaces will offer little resistance to fire as a result of free air circulating, unless the fire is extinguished by some sort of suppression system. • There may also be open stairways, lifts, ill fitting doors and ceiling voids that will offer easy pathways for fire and smoke to circulate throughout the building. • Materials used in construction should also be considered as depending on the type of materials used they will be have in different ways. Fire Growth – Fire and Heat Spread The four methods by which the heat difference may be transmitted either singularly or in combination are: Conduction - this is where heat is transferred through solids, liquid or gas (although most common in solids). For example, heat transfer the structure of a building. Copper, iron and steel are good conductors. Can be prevented with insulating with fire resistant materials. Convection - convection only occurs in liquids and gases. When a liquid or gas is heated it expands and therefore becomes less dense. The lighter liquid or gas rises, being displaces by cooler and therefore denser liquid or gas. The cooler liquid or gas in turn becomes heated and so a circulation is set up. Can be prevented with good separation and compartmentation of building. Radiation – radiated heat is transferred from one body to another by heat rays passing through intervening space. As with light, radiated heat travels in a straight line until it encounters an opaque object where it is absorbed. It can also be reflected and magnified. Can be prevented through space separation and physical barriers. Direct Burning - one of the most common methods of fire spread is where combustible materials are burning and the flames, embers and sparks come into contact with other materials. Construction Materials - Steel – may require surface protection. If it is not protected it may be in danger of collapse when subject to fire or heat transfer. Structural steel will lose 2/3 rds of it’s strength at 600 °C and will distort and sag. Steel is subject to expansion when it gets hot but where it is used as structural beams this might lead to walls being pushed out and subsequent collapse. Aluminium alloys are increasingly being used but they have a lower melting point and rapid loss of strength between 100 – 225 and their higher thermal conductivity. Steel and alloy structural materials should be protected from the effects of fire and this can be achieved by: • Sprayed coatings. • Intumescent coatings • Solid protection • By design (e. g. suspended ceilings).
Fire Growth – Fire and Heat Spread Construction Materials - Steel Classification of Fires Factors Influencing Fire Growth
Construction Materials Concrete Where this is used in areas where it may be subject to stresses, it is usually reinforced with steel bars. If the bars heat up they will begin to lose their strength and at about 550 °C will lose 50% of their strength. This is known as the Critical Temperature. The bars also act as a conductor of heat and may increase the likelihood of the concrete spalling. Timber When subject to fire conditions timber will act in different ways depending on the type and size of timber used (thin timbers may promote a fire, large section retain structural integrity and the charred surface will act as an insulator. Timber can also be treated with fire retardant materials to increase its level of safety within fires and the application of a coating can increase its classification of 3 or 4 surface spread of flame rating to a class 1 rating. It goes through a Pyrolysis stage when burning occurs and thermal decomposition occurs which causes charring protecting the timber underneath. Brick Readily used in construction as they are non combustible and fire resistant, they may also be used to protect other parts of the structure from fire. The level of fire resistance offered by brickwork will depend on the thickness of the brick itself and also how the brick has been made i. e. hollow bricks tend to be more prone to the front facings breaking away. Smoke Most fire deaths in the UK can be attributed to the effects of smoke whether it is from inhalation or from reduced visibility. In complete combustion the fuel will be completely burnt giving off primarily water vapour and carbon dioxide. Unfortunately, in a fire, complete combustion is rare and so we end up with smoke, which is a combination of unburnt carbonaceous materials and hot gases. These tend to be toxic and will include carbon monoxide, hydrochloric acid and certain cyanides depending on the material being burnt. The movement of smoke depends on the temperature of the smoke. Cold smoke will tend lie at lower levels reducing visibility for occupants, whereas hot smoke will get taken up on air currents towards ceiling and higher and if restricted will spread laterally across ceilings and eventually fill the room. Where large amounts of smoke are being produced from a fire this can happen very quickly. The Principles of Explosion and Explosive Combustion The contents of a building The contents that are used and stored need to be taken into account when considering the risk of fire spread. Materials are rated into either high or normal risk categories and this is based on two tests. The first depends on the maximum rate of temperature rise of a materials and the second is the amount of smoke produced. Some materials will rate high on one, but low on the other but may have an impact. Materials that rate high in both categories are polystyrene and polyurethane and acrylic fibres. Location Where a fire is burning under open conditions (e. g. outside), the heat produced will have very little effect on the materials burning as the heat will rise and disperse. However if a fire is in an enclosed area it may behave totally different and the speed in which it grows can be quite dramatic. There are two particular fire conditions which should be considered. • Flashover – This may occur where a fire is burning in a room with an adequate supply of air. The initial fire will radiate massive amounts of hear and other materials present will eventually reach their spontaneous ignition temperature. • Backdraught – This normally occurs when a fire has started in an enclosed room with little airflow. The fire will burn but use the air quickly, but instead of going out, it will smoulder and produce large quantities of smoke and gases that would normally burn off. The mixture will not burn until it receives oxygen (such as someone opens a door). The fire then receives the oxygen it needs and the unburnt mixture will ignite, normally with explosive force. An explosion is a sudden increase in volume and release of energy in a violent manner and usually includes high temperatures and pressure waves. An explosion can occur when the vapour, gas or dust is within its flammable limits (the right mixture with air). Explosions can be classed as either detonations i. e. the most devastating form of an explosion where the flame front speeds are supersonic or deflagrations where the flame front speed is less than the speed of sound. The chances of a detonation occurring in a fuel / air mixture depends on the type of fuel being used. Some high risk fuels are acetylene or the formation of hydrogen gas from battery charging. Deflagrations occur generally through thermal conductivity where hot burning materials heat the next layer of cold material and ignites it. This will continue until all the material is used up. Potential explosions that could occur in the workplace include: • Unconfined Vapour Cloud Explosions (UVCE) • Confined Vapour Closed Explosions (CVCE) • Boiling Liquid Expanding Vapour Explosions (BLEVE) • Dust Explosions.
The contents of a Building and Location The Principles of Explosion and Explosive Combustion Construction Materials – Concrete, Timber and Brick Smoke
Boiling Liquid Expanding Vapour Explosions Failure of the pressure vessel containing flammable liquid gas on exposure to fire can be due to weakening of the portion of the vessel exposed to the fire, and / or the excessive pressure caused by the effect of heat on the vessel contents. This results in a Boiling Liquid Expanding Vapour Explosion. If a liquid is above its critical temperature, and pressure the liquid will flash immediately to its gaseous state when it expands to atmospheric pressure, and temperature due to the rupturing of the tank or vessel. Damage is caused by: • A blasé wave due to relief of internal pressure. This is not a major consideration except near the event. • Thermal radiation from a fireball produced by the massive burning of the contents of the vessel in the air. • Projection of large fragments for considerable distances on violent rupture of the tank. The main effects are missiles being launched or burns for those who are onlookers or emergency service staff. Dust Explosions Dust explosions are very similar to gas and vapour explosions although in dust explosions we tend to get two explosions, these being Primary and Secondary explosions. Primary and Secondary – the concentration limits needed for a dust explosion rarely occur outside of process vessels, therefore a primary explosion would normally take place in mixers, hoppers and silo’s etc. However the pressure wave and air turbulence created form the explosion may dislodge the dust within the surrounding areas and if that dust is then ignited, by either the initial explosion or another ignition source the consequences can be devastating and this is known as the secondary explosion. Conditions for explosions to Occur For dust or gas explosions to occur then certain conditions need to be present and these include: • The dust / gas needs to be combustible • It needs to be within its flammable limits • Must be capable of becoming airborne • An ignition source present and with dust of sufficient heat energy. • Sufficient oxygen to be present • Particle size of dust to be small enough. Dust Explosions Within the workplace if there is the possibility of explosions occurring then suitable control measures need to be taken and these will include, for dust: Control of Ignition Sources – naked flames, faulty electrical equipment, overheating of plant, impact sparks, electrostatic discharges, spontaneous heating, smoking materials. In consideration of these hazards it is necessary to control all flames and flame cutting equipment, such as using cold cutting or removal of combustible dust. Often permits to work are used to ensure safe systems of work. Use of Inert Atmosphere - When combustible dusts are handled in closed vessels oxygen content can be reduced by the introduction of inert atmospheres (e. g. nitrogen). Control of dust cloud formation - Good housekeeping is vital for controlling dust clouds. Air lines or brushing should never be used. Vacuum systems with filters are effective, or the use of dampened powder or pelletised products. Plant Controls - Process deviations need to be controlled, and as such the plant may require continuous monitoring. Filters used in plant equipment need to be checked to ensure they do not become blocked so dust does not escape. Local exhaust would need to be alarmed and interlocked in case of failure. The use of detectors can help to monitor sparks or flowing materials and set off systems such as water to help cool and extinguish potential ignition sources. Explosion Protection This section accepts the fact an explosion has taken place, and considers the measure necessary to minimise the effects of the explosion on plant and people. The main types of explosion protection include: • Explosion Relief Venting • Containment and Suppression Explosion Relief Venting This is the most common and simplest methods. It introduces a deliberate point of weakness into the system, which is an explosion relief vent. To work successfully, the vent must activate at a pressure well below that which the plant it is protecting can withstand. Vents are normal in the form of a lightweight panel or door weighing less than 10 KG/m 2. Vents need to be sited correctly so to be clear of obstruction so release is not inhibited. Vents need to be restrained so they do not become missiles. If a secondary explosion is likely, the vent should not discharge inside the building. Explosion Suppression Explosion suppression systems are often used on major plant items. The suppression system will detect an explosion in it’s early stages by the increase in pressure and a sensor linked to a rapid acting device that injects a suppressant material into the duct into the path of the explosion thus not allowing the flame front to proceed. This can be in the form of dry powder, or water as used in fire extinguishers.
Dust Explosions Explosion Protection Boiling Liquid Expanding Vapour Explosions Dust Explosions
Causes and Prevention and Fire Causes of fires can be divided into two main categories; those that are started accidentally and those that are started maliciously (arson). All fires that are attended by the fire service are recorded and used to compile statistics. These show more fires start between 18. 00 – 06. 00 than during daytime hours. It is considered that accidental fires are responsible for more than half the fires in the UK, and these are caused by: • People’s actions – this can involve the misuse of equipment or appliances or careless actions. • Defective Equipment – The use of defective equipment in the workplace can have serious consequences for example, maintenance costs could be high so the frequency is lessened. For a fire to start (in most cases), there has to be a source of ignition present and it has been found that for accidental fires the most common sources include: Sparks from equipment or process, static electricity, welding, non intrinsically safe equipment used in a flammable atmosphere, smoking materials, hot surfaces, portable heaters, cooking equipment, overloaded electrical circuits and light bulbs. Fire Risks in Construction and Maintenance Work Serious fires tend to happen in existing buildings when either construction or maintenance work is being carried out. It is important to realise during these periods, extra fire precautions may be needed and existing fire risk assessments reviewed. If any fire detection is deactivated due to the work, it is essential compensatory measures are put in place. Extra patrols may be needed. When carrying out the assessment it is worth considering: • The loss of exits and escape routes. • Increase in the amount of flammable substances. • Uncontrolled storage of substances. • Accumulation of waste materials including packaging materials. • Wood and sawdust in work areas. • Burning of waste material (bonfires) • Hot Work (welding, cutting tools) • Bulk Storage Issues. Fires caused by Electrical Appliances Examples of defective equipment or people’s actions that may lead to fires starting include: Lead wires damaged, lamp taken into explosive atmosphere / placed against flammable material, storage of materials on space heaters, portable heaters not taken out of commission, temporary electrical installations not complying with IEE rules, electric motors, loose connections, inadequate maintenance, static electricity not properly controlled. Lightning Lighting strikes may cause power surges or heating of cables or other equipment. Any building has the possibility of being struck although taller buildings, large plants and tank farms may be more at risk. Cooking It is common practice now that employers will provide either fully catered facilities or an area where they can prepare food for themselves. This can cause a number of hazards such as: faulty cooking / electrical appliances, cooking appliances left on or unattended, use of flammable oils or fats, clothes etc left near a source of ignition (e. g. on a heater, grill or hob). Heating and Lighting Systems The misuse of fixed / portable heating systems and lighting equipment by employees may result in fire. Common fire hazards from these different types of equipment will include: Inappropriate lighting equipment, local or task lighting places near combustible materials, covering vents on heating systems, use of space heaters. Welding and Cutting Operations Welding, cutting and other flame using gear has created many fires and proper control is essential to reduce this potential. Work must only be carried out after a site inspection and work permit has been issued. Ensure a fire operative trained in the use of fire fighting equipment is available. If work is being carried out above other plant or flammable material, remove the items or cover with flame resistant blanket or covers. Ensure work area is free from other hazards. If oxygen is being used in a confined space beware of producing an oxygen rich atmosphere. Ensure hose lengths are kept to a minimum. Close all valves on the cylinders when not in use. Do not use greases or oils on valves. Use of non return valves and the fitting of flashback arresators.
Fires caused by Electrical Appliances / Lightning / Cooking / Heating & Lighting Systems Welding and Cutting Operations Causes and Prevention of Fires Fire Risks in Construction and Maintenance Work
Motives for Arson Waste Disposal It is important to consider the types and sizes of waste produced when considering waste disposal. Waste should never be allowed to accumulate, so regular removal is required. Waste materials are a ready source for fuel so suitable storage areas should be considered and the position of waste skips so as not to promote the spread of fire. Waste building materials should only be by a licensed waste contractor to a recognised landfill site. It is important to ensure that fire or explosion hazards are not created so several questions need to be answered. • Is the waste easily ignitable? • Is there the potential for the formation of a dust cloud if the waste is disturbed? • Are flammable vapours given off the waste production? • Are the materials to be disposed of incompatible? A study in the 90’s of reasons why arson is committed, proposed for a three tier system: Arson with a motive • Insurance fraud • Contractual matters • Intimidation • Concealment of other crimes • Revenge or jealousy • Racial / ethnic Motiveless Arson • Clinical psychosis • Pyromania • Criminal damage • Mental disorders / incapacity • Alcohol or drug abuse Juvenile Fire Involvement • Fire Play • Fire Setting • Motiveless Arson Studies undertaken so far only seem to be a small step in gaining an understanding of the psychology of arsonists and the subject is still seen as a new science. Are you at Risk? Arson Results of are attacks are: Loss of life and injuries, business interruption, financial losses, damage to the environment, loss of goodwill from customers, heritage destroyed. Arson costs an estimated £ 1 m per day insurance and that over 50% of all fires causing losses in excess of £ 250, 000 are as a result of arson. Annually more than half of the £ 800 m direct costs of fires are attributable to arson. Arson fires tend to be much bigger and costly because they are normally started under ideal fire conditions in that: fuel may be brought on site to assist the fire, fires may be started in vulnerable areas of the building, sabotage of protection measures, ventilation may be aided by leaving windows and doors open. Arsonists tend to work under the cover of darkness so more likely to happen during the night or darker months. Several factors will influence whether your business is at risk: Location • Is the business in an inner city area? • Are the premises isolated? • Does the are have a high rate of criminal activity? • Has the area suffered a higher than average number of fires? • Are there empty premises surrounding your property? Security • Is there a perimeter fence and is it in good condition? • Are there areas that have no lighting or poorly lit? • Is CCTV installed, and does it cover all areas of the site? • Are bushes and hedges overgrown? Access • How many entrances are used to gain access to the site? • Are all windows and doors closed during periods of inactivity? • Are there restricted areas on site, are they adhered to?
Arson Are you at Risk? Waste Disposal Motives for Arson
Are you at Risk? Examples of reducing the risk are: • Prohibiting smoking to designated areas • Storing fuel in locked containers. • Pruning trees to prevent access to roof tops • Trimming hedges to prevent cover for arsonists • Adequate lighting outside • Windows and doors in good repair and locks working • Security access control to the building • Gaps beneath doors needs to be sealed to prevent lit paper being put under. • CCTV used as a deterrent and means of detection. • Rubbish not allowed to accumulate. Skips should be at least 6 metres away from the building. • Staff awareness and training on risks or arson, intruders etc. Other Fire Prevention and Precaution Measures Daily checks – a simple check of the premises at the start of the day will help ensure a property is safe to occupy. Inspection – Under Article 17 of the RRFSO there is a requirement to maintain fire safety within the workplace, and to assist this companies need to carry out inspections of the workplace. The purpose of the inspections are to: • Aid in the prevention of fires. • Ongoing staff awareness of Fire Safety. • Monitor fire safety performance. • Ensure means of escape are maintained. The frequency of inspectional may be weekly, monthly etc but should be determined by the level of risk within the business. Prevention of Electrical Fires Safe Systems of Work • Ensure PPM of all equipment and circuits is carried out. • Ensure temporary circuits are temporary. They should comply with IEE regs and three A step by step procedure that will enable a task to be carried out safely and is agreed by management and employees. When a SSOW is designed it is usual to take into account the fire hazards associated with the: • People – training, behaviour, fire awareness, knowledge, and level of supervision. • Equipment – safe to use in environment, maintained and inspected. • Materials – type present, form of the materials (e. g. dust, gases). • Environment – heating, lighting, ventilation. months duration maximum. • Provide correct equipment in flammable conditions. HSE code of practice C. P. 1003 -1, 2, and 3. • Ensure good housekeeping. • Keep electric motor vents clean and no storage across them. • Equipment used is dust atmosphere should be totally dust excluding. • Where materials may generate static electricity, earthing and bonding is necessary. Humidification or Ionisation may be needed to prevent static from forming. Lightning Where lighting conductors are installed as on tank farms, these should be maintained top ensure lightning strikes would be directed along a desired route and also: • High enough to prevent a fire occurring from an arc on contact. • Continuous through to earth • Kept free of corrosion and any properly earthed if large enough. • Must not pass near any other potential conductors • Must not pass through flammable material and earthing must be at least two points. Safety Procedures – This should be developed to establish control within the company to ensure fire hazards / risks are not imported into the workplace. Procedures would also need to be established at purchasing and procurement level to prevent incorrect equipment and materials being present. Permits to work – Organisations use a range of PTW’s but the essential one in regards to fire is the HOT WORKS Permit. This would be used whenever any hot work such as welding and cutting is being undertaken. The permit would typically include: Statement of the work, description of plant, warning of residual risk, how the plant has been made safe, precautions to be taken, emergency procedures, name of responsible person, authorised persons working under the permit, signature and release times, acceptance and completion.
Prevention of Electrical Fires / Lightning Safe Systems of Work Are you at Risk? Fire Precaution and Prevention Measures
Control of Contactors Having contractors on site can increase a risk of fire. This can be due to the nature of the work, poor selection of contactors or the lack of control when they are on site. Under the RRFSO it is the duty of the responsible person to consult with other person and to ensure that they understand the preventative and protective measures in place. A number of safety passport schemes exist such as the Client Contractor National Safety Group, and as well as health and safety, fire prevention is also assessed. It is reported that where such schemes are in use, incidents of fire have reduced by up to 50% Maintenance It is an organisations responsibility to ensure standards for maintenance are observed and implemented, and equipment is properly maintained which will enhance it’s working life and reduce the risk of failure or risk of injury to people or fire. It is good practice to have planned preventative maintenance in place of any critical equipment. A plan will set out when and how often equipment should be inspected, serviced and maintained and detail the competency of the persons carrying out the work. Storage of Flammables There are requirements for the correct storage of flammables. The Control of Major Accident Hazards Regs 1999 (COMAH), give specific guidance and requirements for storage and controls. Flammable materials should be kept well away from sources of ignition and stored in well ventilated areas to prevent the build up of fumes. Leaks should be controlled to avoid the build up of vapours which can be heavier than air and travel large distances. The guidance is that up to 50 litres can be stored within the workplace providing that a fire resisting cabinet or bin is used. LPG’s are also a significant concern. The total amount to be kept at a premises should be to a minimum and below 70 kg. Full and empty LPG’s should be kept separate and within secure locations, either in open air or in a ventilated store room. Fire Protection in Buildings – The Building Regulations 2000 The primary role of the regulations is concerned with the aspects of the building design and construction, which apply to new premises and material alterations to existing ones. The regulations detail the requirements with which building work must comply and these include requirements for fire safety. The regulations are subdivided into fourteen approved documents – Part A – Part P. Approved document B (guidance on Fire safety to the Building Regulations) provides extensive and sometimes complicated guidance on what is required and need to be studied in depth to extract all the relevant requirements. The document is split into two volumes and it is volume 2 that details the requirements for buildings other than dwelling houses. B 1 – That there is a satisfactory standard of means of escape for persons in the event of fire in a building and the means of giving an alarm for fire. B 2 – That fire spread over the internal linings of the building is inhibited. B 3 – The ensure the stability of buildings in the event of fire, fire separation between buildings, automatic fire suppression where needed. B 4 – That external walls and roofs have adequate resistance to the spread of fire. B 5 – To ensure satisfactory access for fire appliances to the building. Elements of a Structure Within approved document B elements of a structure is a term applied to the main structural load bearing elements of a structure which may include: • Structural Frames of a building or other beams or columns • A floor • Load bearing walls or load bearing parts of walls. • An external wall • A compartment wall (although not necessarily load bearing). The requirement for fire resistance for elements of a structure Within buildings the principle of fire resistant structures is to ensure the integrity of any fire compartments. Fire resistant materials may be made of blockwork, brickwork, and plaster finishes which may give over 60 minutes of fire protection. Hollow stud walling with plasterboard on either side finished with a skim of plaster will give 30 minutes. It is not always easy to tell if a material is fire protecting or not so use of approved contractors is recommended.
Storage of Flammables Elements of a Structure Control of Contractors and Maintenance The Building Regulations 2000 – Approved Document B
Compartmentation to Inhibit Fire Spread Factors Affecting Fire Resistance The fire resistance of an element of construction is a measure of its ability to withstand the effects of fire in one or more ways including: Resistance to collapse – the ability to maintain its load bearing capacity. Fire Penetration – the ability to maintain its integrity so that fire and smoke will be unable to penetrate the structure. Transfer of excessive heat – the ability to produce insulation at high temperatures so other items on the other side will not ignite. A number of factors will need to be considered when assessing the degree of fire protection needed. These are: • The likely fire severity • Numbers and type of people within the building • The height of the building. The spread of fire within a building can be restricted by sub-dividing buildings into fire compartments by means of walls and floors constructed of fire resistant materials along with fire doors. The object of this is two fold: 1 – To prevent the rapid fire spread which could endanger lives. 2 – To reduce the chances of fires becoming large as these pose a bigger risk. Building regulations limit the size of compartments in some types of building. The size is dependant on the use and load of the building, the height and availability of a sprinkler system. Compartments will normally withstand fire for 30 minutes but may be designed for longer periods according to the design, purpose and use of the building. The compartment should minimise any damage to the building by confining the fire and fire spread. Stairways should also form separate compartments to limit vertical spread. Where there are opening in compartments, there is always potential for fire and smoke to penetrate. A common example is the incorrect use of fire doors. Other common devices used for protection include fire dampers for ductwork and steel shutters in wall openings. In large opening in area like false ceilings, control of spread can be gained using fire blankets to create a barrier and prevent spread. Internal Fire Growth and Lining Materials Common Failures in Fire Resistance Some construction materials that are used in modern buildings are a concern, most notably the use of the sandwich panel. Sandwich panels consist of two outer linings of sheet metal which are then infilled with a heat resistant material such as polyurethane or certain foams. When buildings are on fire it has been known that the panels fall out of their frames and can cause a collapse of the building. Once the foam infill is on fire, this can lead to fire spread. Wherever work is undertaken and holes made, it is important to use good fire resistant material. This is now normally achieved by the use of intumescent materials that upon contact with heat are designed to expand then act as insulation thus reducing the rate of heat transfer. This is know as fire stopping. Internal linings mean the materials or products used in lining any partition, wall, ceiling or other internal structure. When determining the risk of fire spread and its growth in relation to the lining materials used the following properties should be considered. • How easy does the material ignite? • How fast will flame spread across the surface of the material? • How fast is heat released from the material? • How much smoke is produced by the material? Room linings should not be easily ignitable, so should be considered as part of the assessment, as they may contribute to the phenomenon called ‘flashover’. Appendix A in Approved Document B describes the different classes of performance of materials and the appropriate methods of test which are discussed next. Surface spread of flame test This test is used to establish if material has a surface spread of flame that is either class 4 (being the worst) through to class 1 (The best). Class 0 is often quoted for some materials these being class 1 that have undergone a further test to ensure they will not contribute to the propagation of fire. Class 0 are often used in escape routes.
Common Failures in Fire Resistance Internal Fire Growth and Lining Materials Factors Affecting Fire Resistance Compartmentation to Inhibit Fire Spread
Surface Spread of Flame test This test is used to establish if material has a surface spread of flame that is either class 4 (being the worst) through to class 1 (The best). Class 0 is often quoted for some materials these being class 1 that have undergone a further test to ensure they will not contribute to the propagation of fire. Class 0 are often used in escape routes and circulation spaces where requirements are more stringent. Suitable materials for use to limit spread and growth of a fire would include: • Exposed brickwork • Mineral fibre board • Exposed block work • Plasterboard and skim • Fire retardant coatings Means of Escape The definition is: Structural means whereby (in the event of a fire) a safe route or routes is provided for persons to travel from any point in a building to a place of safety. By looking at each component we can ensure that our premises provide a suitable means of escape. Structural – would normally form part of the structure of the building and therefore generally unacceptable means of escape include throw out ladders and chutes, as they cannot be relied upon. Travel – It should be possible to travel away from the fire, not travelling excessive distances to a safe place. Place of safety – This ultimate place of safety should be in the open air and clear from the effects of the fire. However where this is not possible, an area of comparative safety may be used such as a protected stairwell, whereby they can then continue onto a place of safety. BS 5588 Part 11 and Approved Document B give more guidance on this. External Fire Spread Principles for Design of a Means of Escape The construction of external walls and separation between buildings to prevent external fire spread are closely related. The chances of a fire spreading across an open space between buildings and the consequences of it depend on: • The size and intensity of the fire • The distance between the buildings • The fire protection given by their facing sides • The risk presented to people in other buildings. The objective of these factors is to limit the spread of fire to any adjacent buildings. The elements of a structure will have a minimum of 30 minutes fire spread and in most cases 60 minutes dependent on the distance between buildings. The distance is usually 1 metre however if the space is less, the regulations impose other requirements on the nature and type of materials that can be used. • Turn aware from the fire and process along a recognisable escape route. • Alternative Escape Routes • No excess travel distances • Escape routes must lead to a place of safety • Limitation of routes through access rooms. Basic Occupancy Calculations The principles of these based on that depending on the situation, a person will require a certain amount of space measured in square metres. Some typical occupancy factors are: Offices Standing Areas in Bars etc Dining Rooms Factory Areas, Workshops etc 6. 0 m² 0. 3 m² 1. 0 m² 5. 0 m²
External Fire Spread Means of Escape - Continued Surface Spread of Flame Test Means of Escape
Requirements for Means of Escape When considering if the means of escape is adequate, the assessor should consider the following aspects: Escape Routes – Most escape routes will normally be entrances / exits that are provided for every day use. Protected Routes – to ensure that peoples route out of the building will not be compromised in the early stages of a fire, so stairways and corridors need to be protected. Alternative Exits – where possible there should be alternative exits available, but where this is not always possible, fire protection needs to be determined by risk. Where alternative exits are provided they should normally be located at 45° apart unless the route to them is separated by fire resisting construction. Travel distances – The distance travelled to a place of safety. There is no set legal limit for distance, however guidance documents should be considered. Acceptable distances should be done on risk, number of escape routes. Some examples are: Where more than route is provided – 25 m in high risk, 45 m in normal risk, 60 m in low risk. Where only a single route is provided – 12 m high risk, 18 m normal, 25 m low Corridors – these should be sub-divided with self closing doors where less than 30 m in length (45 m in offices and factories). These need to be constructed of fire resisting material when leading in one direction only or when serving sleeping accommodation. It is essential that corridors are free from obstructions, tripping or fire hazards and as a minimum would normally be 1 metre wide. Fire doors serve two purposes: • To prevent the spread of fire and smoke • Ensure a means of escape for people in the building. Escape doors should always open in the direction of travel where they are used by more than 50 people, at or near foot of stairs, exit from high fire risk areas and if they are in areas used for public assembly. As a rule of thumb a fire door should: • It will normally have three hinges • Not be restricted from closing (e. g. self closing or percomatic closer fitted) • New doors will be fitted with intumescent strips and smoke seals. • New doors should have a coloured plus inserted into one of it’s edges. Requirements for Means of Escape If an escape route leads to an alternative exit but initially only allow travel in a single direction, ten that distance should be treated as a ‘single route’ provided distance, yet total should not exceed that of ‘more than one route’. Distances are measures from the furthest point in the room to the final exit or to a vertical storey exit. Access Rooms – Route from inner room through access rooms should be avoided unless those in inner rooms have means of awareness of fire (i. e. vision panel, automatic fire detection or min 500 m gap between partition wall and ceiling). High risk areas should not be used for access rooms and inner rooms not used for sleeping. Stairs and stairways – should be sufficient and adequate in size. Width of stairs should be no less than 1 metre and not excessively wise with handrails and should not reduce in width at any point. Low risk workplaces, not more than two floors should not exceed less than 45 m for one exit, and 60 m for more than exit. Accommodation stairs (additional to means of escape) need not be protected provided they do not link more than 2 floors and are independent of protected routes. Requirements for Means of Escape The colours of the plugs donate the fire standard of the door. This is: • A white circle with a red dot is an FD 20/20 which required intumescent strips to be fitted. • A white circle with a green dot is an FD 20/20 which does NOT require intumescent strips to be fitted. • FD 30/30 means that it is a fire door, which has a 30 minute stability rating and a 30 minute integrity rating. Stability – is the time at which the door collapsed during test. Integrity – is the time that cracks and other openings exist whereby hot gases and flames passed through the door and caused flaming of a cotton wool pad under test. Lighting and signs – once the design and the provision of means of escape have been fulfilled it is essential to ensure that is can be safely used and as such it will need to be maintained. Where the means of escape has no natural or borrowed lighting then the provision of artificial lighting will be required.
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Requirements for Means of Escape Lighting – it is usual to install a form of secondary lighting in the event of a power failure. The provision of emergency lighting is a requirement under the RRFSO where escape routes need to be illuminated, and other legislation such as the building regulations. Emergency lighting should clearly indicate escape routes and provide adequate illumination and indicate call points and fire fighting equipment. Emergency lighting can either be: • Maintained – the lighting is on all the time • Non Maintained – the lighting only operates when the usual lighting system fails. The lighting can be incorporated into existing light fittings or can be stand alone which would normally be powered by batteries or an automatic start generator. There may also be used photo-illuminescent materials or lines of LED’s that can be used to mark escape routes at low levels. Most lighting needs to be manually tested (unless self testing), and this should be done as follows: Daily – check for faults and normal power, if a ‘maintained system’ then check for the LED lamp, fault found to be rectified and recorded. Monthly – a monthly function test to ensure the lighting is energised under conditions of a power failure. Annually – a full check and discharge test of the system by a competent engineer. Requirements for Means of Escape Signage – There are two acceptable types of fire safety signs: • BS 5449 – a white pictogram on a green background which depicts a person running, framed in a doorway which is an exit. These signs may or may not have directional arrows. • EC Directive signs – a white pictogram on a green background a plain white block denoting an exit, again with or without directional arrows. The purpose is to ensure that a means to an exit can be seen from any part of the building. Where there is a choice of route, the directional signs should lead to the shortest route and place of safety. Maintenance of escape routes – regular inspections should be carried out to ensure escape routes are free from obstructions and hazards. These include: • Portable heaters • LPG cylinders • Boilers and cooking appliances • Stored furniture and coat racks • Temporary stored items such as waste bins etc • Photocopiers, vending or gaming machines. Requirements for Means of Escape Fire Safety Records – it is important to keep up to date records of your fire risk assessments as this will allow you to manage fire safety properly. It is good to keep records that demonstrate that you are inspecting, maintaining and servicing items such as: • Means of escape – routes, signs etc • Fire fighting equipment • Fire detection and alarms • Emergency lighting • Instruction and Training • Fixed equipment including sprinklers, smoke venting etc • Assembly areas • Alarms • Lighting and signs • Instruction, training and drills These records can be kept in the fire log book or in some other suitable format. Requirements for Means of Escape – Means of escape for disabled persons People with hearing or sight impairment, or mental illness or staff or visitors with impairments (temporary or otherwise) may be at risk during a fire. Most people of this nature will be able to use normal means of escape but if they are a wheelchair user special consideration must be given due to the possibility of space constraints and getting a wheelchair down stairs. In some cases like these, this would involve the use of refuge areas, evacuation lifts or other facilities. Evacuation Lifts – Designed in accordance with BS 5588 (fire precautions in the design and construction of buildings). The lift would normally be in a fire resistant enclosure and have a separate power supply from the main building. Refuges – A refuge area is a place when someone can wait in relative safety until assistance arrives. Refuges should be part of or open up onto protected stairways and have a minimum of 30 minutes resistance. If staff or visitors have any visual impairment, the use of tactile surfaces (textured surfaces denoting edges or routes) should be considered. If staff or visitors have hearing impairments the use of flashing lights or a vibrating pager should be considered to help alert in the event of a fire.
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Requirements for Means of Escape Fire Detection and Fire Alarms Evacuation plans – it is important to consider disabled persons in evacuation plans and any arrangements developed are recorded. It is best to use a Personal Emergency Evacuation Plan (PEEP). This will include specific needs of the person. Where it is likely that people will need assistance other than your own employees then it is also advisable to have a similar system to a PEEP but called a Generic Emergency Evacuation Plan (GEEP). This may require that the person is evacuated down a protected stairwell and it is unlikely that a wheelchair can be taken this way since it may cause an obstruction or fall. In these cases the use of an evacuation chair may be helpful. These however must only be operated by trained people so as to minimise risk to other people and to those operating the chair (such as manual handling injuries). Such chairs usually only operate by taking someone down the stairs rather than up. The best possible fire alarm system should be designed and installed as to be: • Electrical – equipment and wiring to be exclusive to that system. • Power Supply – battery operated, trickle charged from mains supply. • Cable – MICC, hard metal sheathed, cable in conduit (external overhead lines, underground cables) • Call points – to give continuous signal. • Signal - audible visual, standard throughout, distinctive. • Central point – indicator board, switchboard, to fire brigade. The system may need to actuate auxiliary services such as call points which may actuate fire extinguishing systems, close windows or doors, open or close tank valves or close cover tanks. Fire Detection and Fire Alarms The purpose of a fire alarm is to warn occupants of a building to a fire situation. This is usually achieved by an audible warning device such as a bell or siren. Any audible alarm should be capable of being heard over any background noise and distinguishable from other noises. Considerations must be made for the hearing or sight impaired. The simplest of systems are manually operated such as word of mouth, bells, whistles, hand operated sirens. Though relatively low cost and readily available, they are limited in cover of area and only if someone is operating them (which they may not be in smoke filled room) or they may be stolen or lost. A lot of systems are now going to stand alone call points and sounders. The benefit of these being that once operated the person does not have to stay in the area, but the sounder must still be heard. Systems are set in motion by hand then derive their power for operation from a non-manual source. These will continue to sound until switched off and can be costly to install. Call points – This is normally the standard method of operation for a fire alarm system. Employees should know where their nearest call point is and how to operate it. Where there are call points, the following should be considered: • Sited – on escape routes. • Distance – Positioned so that no person has to travel more than 30 metres (45 actual) to operate an alarm from any part of the premises. • Uniformity – throughout the premises. • Safe Position – operator must not be exposed to undue risk. • Conspicuous – well illuminated (day or night). • Height – 1. 4 metres above floor level. This may need to be lowered to accommodate wheelchair users. • Operation – standard throughout the premises. Audible Range • Minimum of 65 db is required in normal areas or 5 db above any background noise which persists for more than 30 seconds. • Where high noise levels exist the use of visual warnings to be used. • Where sleeping is available, then 75 dv is required at the bed head. • A loss of 5 db per door should be considered, therefore a sounder per bedroom is needed.
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Fire Detection and Fire Alarms Fire Alarm Zones – zoning is a convenient way of dividing the building up into manageable areas to allow a fire to be quickly located. Zoning features include: • The floor area of any zone should not exceed 2000 m². • A building with a floor area of less than 200 m² may be considered as one zone. • A zone should normally cover one storey only (unless it is a shaft) • The maximum distance to locate a fire should not exceed 60 m. Alarm receiving centres – this is a centre that is manned 24 hours a day, provided by commercial fire organisations that alarm systems are linked to. The operator taking the call would then contact the fire and rescue service. Fire Detection and Fire Alarms There are many factors to consider when deciding on what type of system to install. These are: Property Risk – where the organisation is looking to protect property only by using AFD’s then a type P system may be used. Type P’s are subdivided into: • P 1 – Automatic detection installed throughout the entire building to be protected. • P 2 – Automatic detection in designated areas only. When installing P systems it is important to consider that property risk does not also prevent a life risk. Life Risk - Where there is a risk to life, the objective is to protect people loss or injury, then a type L system needs to be installed. These are divided into: • L 5 – specific life safety objective to be covered (usually risk assessment based) or where P 1 insurance requirement. • L 4 – Detection required through escape routes. • L 3 – L 4 – Plus detection required in all rooms directly off an escape route. • L 2 – L 3 - Plus detection where a fire may grow undiscovered. • L 1 – Total coverage of premises for life protection. Fire Detection and Fire Alarms Behavioural and Social Issues – as part of the risk assessment, the behaviour of people should be considered. People tend not to behave how we expect them to when exposed to a fire alarm and may not evacuate immediately or in an orderly manner. Fire marshals may need to be appointed to ensure timely and complete evacuation, and practice drills should be carried out to ensure people display the correct behaviour. Behaviour can be linked to social issues such as peer pressure, such as waiting for someone else to move. In some cases coded alarms may alert fire marshals and associated staff which then prepare for the full alarm which helps prevent panic and distress. This is good when where is a large number of people such as shopping centres or nightclubs. Fire Detection and Fire Alarms False (Unwanted Alarms) It is thought that about 93% of calls to the fire brigade are as a result of false actuation of systems. . Common causes of false alarms are: Cooking, Steam, Cigarette Smoke, Dust, Insects, Aerosol Cans, Processes, Hot Work, Malfunction. False alarms result in business disruption, loss of profit and loss of credibility. False alarms should be recorded in the log book so that it can help diagnose and correct any problems later. Multi sensor detectors are becoming more common to reduce false alarms. These are where a detector will contain more than one sensor (heat and smoke) and the signals from that are analysed to determine where the signals are indicative of a fire. If there a large number of false alarms from one premises it may mean that the level of response is reduced from the fire service if the issues are not corrected properly.
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Fire Detection and Fire Alarms Testing of Fire Alarms: If a system is connected to the fire brigade or remote manned centre, then the system should be isolated or termination point notified prior to the test. All occupants of the building should be notified that a test will take place. Daily Inspection Check that the panel indicates normal operation. Weekly Inspection • For systems with less than 13 zones: Actuate system from one trigger device • For systems with more than 13 zones: actuate system from the necessary number of zones to ensure that the interval between tests does not exceed 13 weeks. • Record location of point tested in log book. • Visual examination of battery and connections. Quarterly Inspection (by suitable qualified person) • Ensure any defects previously noted in log book have been dealt with. • Check batteries and connections and where applicable check secondary batteries. • Test primary batteries. • Check alarm functions and control indicating equipment. • Check siting of all call points and trigger devices. • All further checks specified by manufacturer or installer. Fire Detection and Fire Alarms Annual Inspection (by suitable qualified person) • All tests as list in quarterly inspection. • Each detector to be operated (other than those designed to operate once only). • Visual check of cable and fittings. Tri-Annual Inspection Testing in according with the requirements of ‘Regulations for Electrical Installations’ published by the Institute of Electrical Engineers. Any defects should be recorded in the log book and actioned. After a fire (whether automatically detected or not. A simulated test should be carried out on each trigger device that may have been affected by the fire. Visual check of batteries and charger. Automatic Fire Detectors (AFD) Automatic Fire Detection Systems are designed to give warning to persons in a protected building of an unusually rapid rise in temperature, excessive temperature and thereby reduce the risk of injury to personnel and damage to property. The automatic fire detector makes no attempt to hold the fire in check. It’s only function is to give notice of abnormal conditions. Fire Detection and Fire Alarms Fire Hazard Detection Situations Strictly, a fire detector can only operate after a fire has started. However, other situations may include: • A dangerous environment is developing but ignition has not yet taken place. • Visible smoke is being produced. • Visible flame is being produced. • Temperature is rising at a dangerous rate. • Temperature has reached a predetermined danger figure. • Heat generated is giving rise to lifting and oscillating thermal air currents. Fire Detection A number of different detection methods have and are being used to detect fire. These include: • Spot Detectors – a static detector covering a certain area of a building. • Line Detectors– heat detector cables laid in specific areas. • Beam Detectors – used to cover large areas (usually an infra red beam). • Sampling Detectors – air is sampled from an area through a range of pipe work back to a detector head. • Scanning Detectors – sweeps large areas. Fire Detection and Fire Alarms Pre-Fire Situation Detectors Gas and explosive mixture detectors – these detectors are used extensively in mines, ships, engine rooms, flammable gas and liquid storage areas or where ventilation is restricted. Smoke Detectors These are of two basic types. One employs the flow of electric current through an ionisation chamber. The second operates on the variation in light intensity on a photo electric cell. Detection by Ionisation Chamber – In this system, a close circuit incorporates two ionisation chambers, which act as resisters, one of which is open to the atmosphere. If smoke or other particles of combustion enter the open chamber, ions attach themselves to the molecules of the combustion products and this causes a decrease in the current flow through this chamber. This alters the voltage balance across the two chambers and operates the alarm. A photo electric cell whose electrical properties change when exposed to light. Several applications include the obstruction of light by smoke and some of the reflection of light on particles in the smoke cloud to increase the amount of current generated. Beam Detectors – A transmitter emits an infrared beam to a receiver and any obstruction by smoke will activate the alarm. Heat Detectors – these operate two principles of detection: • Fixed temperature – detection of a predetermined unsafe temperature. • Rate of Rise – detection of a predetermined unsafe rate of rise in temperature.
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Fire Detection and Fire Alarms Heat Detectors Suitable in most buildings, have greater resistance to adverse environmental conditions. Where fires occur in which is evolves rapidly with little smoke, they may give more rapid fire detection. Heat detectors need to suit the environment, so if there is likely to be fluctuating temperatures by design, the type of detector needs to be considered. Smoke Detectors These give the earliest warning for most types of fire, in which the early smouldering stages of the fire evolve considerable quantities of smoke. Ionisation detectors response most quickly to smoke containing small particles such as those produced by wood burning fires. They may respond less to fire involving polymers. Optical detectors respond better to dense smoke and less to small particles but both types respond sufficiently well to most fires except those involving alcohol which do not produce smoke particles. Optical Beam Type Detectors These are probably the most suitable type for protecting tall compartments, cable tunnels, and open areas. They respond to integrated change in smoke density or temperature over the path of the beam. Not suitable for areas that use blower heaters or waste heat. Factors Affecting Choice – A detector has to discriminate between a fire and the normal environment existing within a building. Each type of detector responds at a different rate to different kinds of fire so a combination may be necessary, as to take into account processes taking place and design of the building and contents. Portable Fire Fighting Equipment It is important to have a basic understanding of he differing classes of fires as this will enable you to determine what types of fires are likely and what equipment will be required. The old colour coding of extinguishers has now disappeared and replaced with the new European standard BS EN 3 whereby all new fire extinguishers have a red body and up to 5% to be coded using the traditional colours. Water – Class A Fires The water extinguisher works by cooling the burning material below its ignition temperature and thus removing the heat element of the fire triangle. These must be kept upright to avoid discharging the gas rather than the water. Extinguishers of this type can be inverted once used to stop water coming out to release the remaining gas. Once used, they will not operate effectively again until they have been recharged. As such, the extinguisher should be regarded as a pressure vessel and maintained according to make instructions. Types Include: • Gas cartridge type – cylinder filled with water and a carbon dioxide cylinder provides pressure when pierced. • Stored pressure type – cylinder is filled with water then pressurised with gas, which expels water when a lever type valve is depressed. Portable Fire Fighting Equipment Foam – (Class A, B and F Fires) Foam works in several ways to extinguish a fire although it’s primary role is to smother the burning material (stops the oxygen portion of the fire triangle). These can be used on class A and B fires but careful selection is required as some foams break down in contact with solvents. Types Include: • Chemical foam – cylinder is filled with 8% sodium bicarbonate solution, the inner cylinder contains 13% solution of aluminium sulphate. When the container is inverted, the two mix together. • Aqueous Film Forming Foam (AFFF) – forms a fire extinguishing water film on the surface of the burning liquid. Has a cooling action with a wide extinguishing application than water on solid combustible materials. Portable Fire Fighting Equipment Dry Powder (Class A, B and F fires, general purpose, Class B special purpose powders) Works by forming a think film of powder on the burning material (smothering effect removing the oxygen part of the triangle). Powder also works by chemically interfering with the fire process and acts as a flame suppressant. These extinguishers are also useful for electrical fires, as they do not conduct electricity (although may cause damage through the mess of the powder, and care must be taken when used inside to avoid the risk of inhaling the powder which can cause respiratory problems as well as having laxative effects. Carbon Dioxide (Class A, B and F Fires) These extinguishers consist of a pressurised cylinder containing liquid CO 2. The gas is discharged by pressing a trigger valve which releases the carbon dioxide snow that turns into gas on contact with heat. These are also useful for electrical fires, but they have no cooling effect so re-ignition can easily occur. The discharge of the gas can be very cold and cause ice burns so care needs to be taken not to hold the horn directly. CO 2 is also an asphyxiant so care needs to be taken when used in enclosed spaces. A class C fire should normally be controlled by isolating the gas or plugging the leak, as using an extinguisher may cause an explosion if escaping gas suddenly re-ignites. Metal fires such as magnesium and other light metals can be extinguished by use of Dry Sand, Soda Ash or Special Powders.
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Limitations of Extinguishers Siting, Installation and Maintenance The main limitation with extinguishers is they can only be used on the classes of fire they are manufactured for. They are also limited by their range of discharge. Some types will only last for a short period and can only be used on small fires. The table below gives examples: Nominal Charge of Extinguisher KGs or Litres Minimum duration of discharge (seconds) Up to and including 3 6 More than 3 but less or equal to 6 9 More than 6 but less or equal to 10 12 More than 10 15 Siting, Installation and Maintenance Generally extinguishers should be sited in a convenient place, easily accessible. A person should not have to travel more than 30 metres from the site of a fire to the location of an extinguisher. Extinguishers are normally location in a conspicuous place on an exit route or signage provided where this is not possible. This should be in the same location on all floors, or where the extinguisher is provided for a special risk (e. g. electrical) that it should be sited near the risk. Fire Rating To try and show the limits of extinguishers they have a fire rating marked on them, although this has only been done for class A and Class B fires. The class A rating is achieved by the extinguisher putting out a specific size of test fire, made up of wood, of a certain length and quantity. For the class B rating, the test is similar although the fire consists of containers of flammable liquids and the rating relates directly to the volume of fuel. Fire Rating BS 5306 Part 8 (Fire extinguishing installations and equipment) guidance is given on provision of a minimum number of extinguishers for class A fires: • A minimum of 2 per floor • Total class A ratings should be no less than 0. 065 x floor area of storey (m 2) minimum 26 A rating. • Single story occupancy with upper floor not greater than 100 m 2 rating of 13 A may be sufficient. For Class B fires it is more complicated and the workplace should be assessed as follows: • Each room considered separately. • Where fire risks are more than 20 m apart as above. • Fire risks within 20 m of another fire risk, assessed as an undivided or divided group. Where there is the possibility of a spillage fire, Class B fire rating is equal to 10 x volume in litres of that spillage. Siting, Installation and Maintenance BS 5306 Part 3 gives the requirements for inspections, maintenance and testing of portable fire extinguishers and these are outlined as follows: Monthly Inspections – should be carried out to ensure no discharge has taken place, no pressure has been lost and no signs of damage, and in its correct location (this can also be done weekly). Annual Inspection and Maintenance – a thorough inspection of the extinguishers carried out by a competent person who will inspect the extinguisher, any spare cartridges and replace as necessary. Test by Discharge – need to be tested by discharge at specific intervals. The interval will be taken from the date of manufacture of the last discharge date. For extinguishers this test is every 5 years, except for CO 2 extinguishers which are every 10 years.
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Fixed Fire Fighting Installations An automatic sprinkler system consists of pipes and heat operated valves (sprinkler heads) by means of which a fire is automatically detected, the alarm given and water delivered to the seat of the fire. The sprinkler heads nearest the fire opens and water flows via the valves and pipework to the fire. The flow of the water through the control valves also causes the alarm to sound. In a large building, the sprinkler system is divided into a number of installations each separate from each other. These have different pipe work systems and the pipes have different names according to their position in the system: Range Pipes – on which the sprinklers are attached either directly or via short arms. Distribution Pipes – horizontal pipes feeding the range pipes. Risers (drops) – vertical pipes connecting: - Installation valves with distribution pipes Or - range pipes with distribution pipes. An installation may be: Wet Pipe – with ALL pipes leading from the water supply through the various controlling valves and to the sprinkler heads permanently filled with water under pressure. Dry Pipe – with the pipes above the installation control valves charged with compressed air under enough pressure to prevent entry of water. On operation of the sprinkler head, the compressed air escapes first and the water follows. This is useful if water pipes may freeze over the winter or in cold rooms etc. Alternative wet and dry – operated as a wet pipe installation in the summer and dry pipe in the winter. Tail end alternate or tail end dry – basically wet pipe installations where a portion of the system liable to freeze is dry or alternative wet and dry. Pre-Action – where a dry pipe system is combined with an independent system of heat or smoke detectors installed in the same areas as the sprinklers. Heat and smoke detectors operate sooner and a pre-action valve opens to allow water to flow into the sprinkler pipework before the first one operates. An example of this is shown on the next card. The sizes of pipes vary according to where they are positioned in the installation and the degree of hazard the installation is designed to meet. Typical sizes are 20 -50 mm internal bore for range pipes and 32 -150 mm internal bore for risers and distribution pipes. Range Pipe Riser Distribution Pipe Fixed Fire Fighting Installations Sprinkler Heads A sprinkler head is a heat sensitive valve which opens, releasing water as a spray when it’s heat sensitive element reaches a specific temperature. The orifice of the head (10, 15 or 20 mm) is determined by the risk. The water distribution pattern depends on the type of detector used. Distribution Patterns Conventional – these sprinklers produce a spherical discharge pattern with some of the water being thrown towards the ceiling. Spray – this sprinkler produces a hemispherical discharge below the sprinkler with little of no water reaching the ceiling. Sidewall – these sprinklers are site close to a wall. They deflect most of the water away from the wall. On a wet system sprinkler heads can be upright or pendent on the pipe work. Dry or alternate systems normally must be upright to allow for drainage, although some have special valves that prevent water being trapped and are occasionally used.
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Fixed Fire Fighting Installations Method of Operation – 2 basic types of Sprinkler Frangible bulb - the sealed glass bulb contains liquid and a small gas bubble which can accommodate some changes in temperature. Very high changes however, cause the liquid to expand sufficiently to absorb the bubble. The result is an increase in pressure which fractures the bulb allowing water to escape from the head. Fusible Link – heat melts the solder allowing the levers of cantilever types to move or the strut types to part letting water escape. Solders are always alloys of tin, lead, cadmium, bismuth and antimony. Temperature Ratings. Sprinklers are designed to operate at a set nominal temperature ranging from 57 to 260 °C. The rating of a particular head can be identified by a colour code. Control Valves The water supply into a sprinkler installation is controlled by a set of installation control valves. Main stop valve controls water entering the installation. Alarm valve situated immediately above the main stop valve and designed to open as soon as a sprinkler head opens and water flows from the installation. Fixed Fire Fighting Installations Alarms Water motor alarms consist of a turbine wheel connected to a rotary clapper mounted within a domed gong and is normally situated outside on a wall. Water flow from the alarm drives the turbine and sounds the gong. Electric alarms can be used as an auxiliary warning device to the water motor alarm to indicate on a central control panel which part of the sprinkler system is operating. Electric alarms can be actuated by two types of switch: • Pressure switch situated either downstream of the alarm valve or on the supply to the water motor alarm. • Flow switch situated downstream of the alarm valve. Water Supplies – water supplies for a sprinkler system need to be reliable, at a suitable pressure and be able to supply a sufficient flow of water for long enough to fight the largest expected fire. They should also be: • Under the control of he occupier of the building or right of use guaranteed. • Free from solid matter which might accumulate in pipe work and cause a blockage. Pressurised water for a sprinkler may be obtained from one or more of: Towns mains, gravity tank or elevated private reservoir , pressure tank where the water is kept under pressure by compressed air (between 2 -10 bars), automatic pumps actuated by a fall in water pressure and draw water from a canal, river, lake or reservoir if needed. Pumps should be either electric or diesel powered and fully operational within 30 seconds of starting.
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Combustion, stages Exothermic Reaction – one that releases energy in the form of heat. Endothermic Reaction - one that must absorb energy Complete Combustion – Occurs when all the oxygen in a reaction is consumed and is the most efficient burning of a fuel (stoichiometric concentration – ideal air to fuel ratio). Stages of Combustion • Induction – this is the early stage of a fire when it is just starting and hear is starting to build up. • Ignition – When the point of ignition is reached and the reaction is self sustaining. • Growth – once ignition occurs, the fire will grow very quickly depending on the oxygen available. • Steady state – When the fire has used all the fuel is used up, and remains in a steady state. • Decay – The final stage of a fire where the fuel is now used up and will eventually go out. Ignition Conditions Flashpoint – is the lowest temperature where sufficient vapours are given off across the surface of the liquid that when an external ignition source is applied, the vapours will momentarily flash (burn). Substances with a flashpoint of less than 32 o. C are known as highly flammable. Firepoint – if the vapours continue to burn, the liquid is said to have reached it’s fire point. This is the lowest temperature at which the heat from combustion of the burning vapour is capable of producing sufficient vapour for combustion to continue. Combustion, stages Flammable or Explosive Limits - for vapours (gases and dusts) to ignite, they must be within a certain ratio with air known as flammable or explosive limits. This is where the fuel to air mixture is at the right limits for the fuel to burn. Too much fuel in the air and it won’t burn (upper flammable limits). Too little fuel (lower flammable limits). Auto Ignition Temperature – the lowest temperature at which the substance will spontaneously ignite. Vapour Density - is the density of a gas or vapour relative to air. Gas with a VD of less than one is light than air and great than one, heavier than air. Lighter gases disperse more readily than heavier gases.
Safety of People in the Event of a Fire Emergency Evacuation Procedures A number of dangers may exist in the event of a fire that may threaten your employees and any other persons on your premises or adjacent to them. It is therefore difficult to construct a single evacuation procedure to adopt for all premises. Any procedure developed should leave no room for ambiguity in what to do in different circumstances. Procedures should be brief and written in simple terms so that they are easily understood. It is essential that the following issues be considered when developing the procedure. • Discovering a fire / raising the alarm • Number of people to be evacuated • Location of assembly points. • Fire Wardens • Disabled Persons • Fire Drill Arrangements • Training if Employees. Safety of People in the Event of a Fire Raising the Alarm What action is necessary when discovering a fire is proportionate to how fire the fire has developed and the speed it is likely to spread. Early fires may be easily contained and not require a full evacuation. Buildings contained hundreds of people may have only a portion of the building evacuation with an alert to other staff that a full evacuation may be required. The procedure needs to enable the fire to be tackled with the least disruption to the business. All staff should be instructed in the location and use of fire alarm call points which should b e operated as soon as a fire is discovered. This should trigger the procedure for then raising the alarm with the fire brigade. Number of persons to be Evacuated In some cases it is relatively easy to determine numbers of people or people tend to be fairly static. In other premises (such as department stores, exhibition halls etc), the number on site can vary throughout the day, time of year etc. Evacuation procedures should take account of likely numbers present and be designed to ensure that safe evacuation of the building can take place. Safety of People in the Event of a Fire Your procedures may be: • Single Stage – this involved complete evacuation of all occupants of the building. • Two stage – allows for a period of time after the initial alarm for evacuation of those in the immediate vicinity of the fire for the fire to be investigated. The alarm is then either cancelled if false, or continues to a full evacuation. • Phased – these are more common in taller buildings where large numbers of employees are working. Occupants on the floor directly above and the floor of the fire are evacuated and the remainder alerted but would remain in the building unless alerted otherwise. If a full evacuation was then required, then this would be carried out two floors at a time. In phased evacuations, communication is essential. A PA system may be used to instruct staff. Fire wardens and senior fire people need good communication and should be by means of telephone on each floor (or radios). Safety of People in the Event of a Fire Location of Assembly Points In an evacuation, people should know where to go and how to get there. When there, they should receive further instructions and be counted (i. e. roll call). An assembly point should be far enough away (although no legal distances are set, rule of thumb is 1. 5 times the height of the building), to ensure those gathering at the assembly point: • Are far enough away to be unaffected by the effects of the fire (e. g. radiated heat, smoke, flying debris). • Do not impede on access to the building of the emergency services or be located where emergency services may set up a control post. The route to the assembly point should be clearly marked and easily identifiable to any person that may be in the building. It may also be necessary to have alternative points for certain emergencies such as a bomb threat and both assembly areas should be made aware to all staff and visitors.
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Safety of People in the Event of a Fire Wardens / Marshals The number of fire marshals in a building depends on several factors such as the number of floors, numbers and types of people etc, but they should be fully trained for the role and responsibilities. Fire Marshals are a proactive part of the fire prevention strategy by helping with inspections, ensure escape routes are clear etc. They also help to aid evacuation in a fire and sweep the building to ensure doors and windows are closed and people are not in areas like toilets etc. The advantages of using fire marshals include: • Quickest most efficient way of evacuating buildings. • Buildings can be split into pre-defined areas ensuring all areas are covered. • Fire and Rescue services can gain quick access to the building to rescue people and minimise damage. • People are used to evacuate people and therefore unusual behaviour can be dealt with. • Fire marshals identify problems during and not after the evacuation. Disadvantages include: • Relies on staff volunteering for the role of a fire warden / marshal • Normally in operation during normal working hours. Safety of People In the Event of a Fire Evacuation Plans It is important to consider disabled persons such as the PEEP and generically the GEEP (as mentioned in means of escape) and the use of evacuation chairs or refuge points. Fire Drills To ensure everyone understands the evacuation process practice drills should be undertaken. This should be done at least twice a year. Two and half minutes is a reasonable time to aim for complete evacuation although this can vary. People can become familiar with their escape routes and may not always know where alternative routes are so it is important to carry out scenarios such as blocking an escape route to ensure people can find an alternative route. Recording any difference in evacuation times may then identify any additional training needs people may have. Safety of People in the Event of a Fire Marshal Systems These include: • Fixed system – in this system, people are fairly static at their place of work. Fire marshals can be given a fixed area of the building to search, so in an evacuation, they would sweep their designated area prior to evacuation. • Assembly System – where persons are not regularly in one place. On activation of the alarm, fire marshals gather at a predetermined position, then sent to check specific areas. This can also be used where the number of fire marshals vary. • Points System – the number of fire marshals may vary and may be moving around the building constantly. There will be fire marshal ‘points’ that contain a route map to be searched. On alarm, fire marshals go to the nearest point collect the route map and search the area. However it may be that too many marshals are at the same point and none at others so good communications is essential in this instance. Staff Training There is a duty on employees to ensure staff are provided with adequate health & safety training and this would include fire awareness training. At a basic level, fire training should cover matters including: • What to do on discovering a fire. • Actions on hearing the alarm. • Summoning of the fire brigade. • Location of assembly points. Perception and Behaviour of people in a fire When planning for fire safety, it is essential to take into account the way people behave when faced with a fire situation. The perception that people will immediately evacuate is not always true. People may: • Stand around and watch the fire. • Ignore the fire and carry on with their business. • May try and use fire fighting equipment despite not being trained. It is only when the fire encroaches in the individual’s psychological safety zone that they start to react to a situation, but any delay may result in being overcome by heat or smoke.
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Safety of People in the Event of a Fire Perception of Behaviour – cont’d It is worth noting that how people behave will depend on the people involved. For example, if people are trained frequently on what to do in the event of a fire then research shows they are more likely to react rationally, react to the alarm, help others and evacuate safely. Some people have a strong tendency to protect others (such as parents, children, friends) and may place themselves at risk to protect them. This happened during a fire in a leisure complex when parents became separated from their children and went away from the assembly points to find them. If people were reassured a good procedure was in place, they would know the children would have been taken care of and reunited with their parents once the danger had passed. Regardless of what legislation, standard or best practices are in effect, we still have to rely on human behaviour for procedures to be successful. People’s behaviour is influenced by both psychological and physiological factors which include their perception, attitude, motivation, and past experiences. Safety of People In the Event of a Fire Visual Warnings Strobe lights – used as a back up to any audible warnings, used in buildings where people have hearing difficulties, or where there is high background noise. Can be a disadvantage if it is where people are not aware of it flashing, involved in high concentration work, or light is not intense enough. Information boards – large modern buildings (shopping centres) may have their system connected to large screens where electronic messages may give visual directions to people to enable evacuation, but it needs to be mentioned that language and reading barriers may reduce effectiveness. Audible Warnings Bells / Sirens – Most common type of warning, which needs to be heard throughout the building. Relies on people reacting to it and fire wardens beginning their duties. Verbal Messages – used in places of public assembly, Pa system uses a pre-recorded message. This may get ignored or it’s importance not recognised. Siren and Verbal – There may be a mix of both systems which may reinforce the message to evacuate. Safety of People in the Event of a Fire Principles of Sensory Perception When considering how to ensure people are aware of a potentially dangerous fire situation we need to take into account how people notice a fire. These include: • Visible flames or sparks • The smell of smoke or seeing smoke. • Excessive heat from a fire If people waited for these, it may already be too late to escape. Other signals may be: • Flashing lights • Bells or other audible signs • The sudden movement of people towards exits. • Loud unrecognisable noises. For warning signs to be effective, they need to be easily recognisable and acted upon by the people at risk. Warnings When confronted with either a audible, visual, verbal or combination, people usually do any number of things which include: • Ignore the warning • Wait to see if it is real • Go and investigate and fight the fire • Raise the alarm and instruct others • Flee from the situation • Fail to respond and freeze. It is a common misconception that people panic in fire, but in the early stages, it is more likely that stress levels may increase which affects decision making processes. Decision Making Process In an emergency it is essential information is given to people in a concise and easy to understand way. Where verbal communication is given it is best to tell people what to do rather than not to do, and give the instructions in the order they should be followed such as ‘please leave the building and go to your assembly point’. Use simple words and point in the direction you want people to go, so it is obvious which way even if they are not taking in the verbal instruction. People will try and use familiar routes so regular fire practices is a big help.
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Fire Risk Assessment A fire risk assessment is a logical organised way to examine your premises and any activities that are carried out within to determine whether a fire could start and level of harm to persons or property. Hazard – something that has the potential to cause harm Risk – the likelihood of harm occurring from the hazard. The objectives of a risk assessment are threefold: • The assessor needs to identify all of the factors that may cause harm to property, people and environment during or as a consequence of fire. • Determine the likelihood of the harm actually occurring. • Allow the responsible person to plan, implement and monitor the measures both preventative and protective to ensure the risks are as low as reasonably possible. There is no universal method for carrying out the inspection, however there are guidance books from the RRFSO, British Standards and PAS 79. The legal requirement is that the risk assessments are suitable and sufficient and should: identify and prioritise the risks, level of details should be proportionate to the risks, remain valid for a reasonable amount of time. Fire Risk Assessment Identify the Hazards – This should include • Sources of Ignition – smokers materials, hot work, naked flames, cooking, heaters, electrical equipment, lighting, static electricity, arson, friction and impact sparks from work processes. • Sources of Fuel – flammable liquids, gases, wood, paper, soft furnishings, metals, waste materials, dust, chemicals, foams, plastics. • Sources of Oxygen – natural ventilation, air conditioning systems, oxygen cylinders, piped oxygen, oxidising chemicals. • Structural features – building structure, wall and ceiling linings, open voids nd any breeches in fire protection. It is important to identify hazards that are considered significant and an assessor may ignore trivial ones. Identify the people at risk Consideration needs to be given to the types of people who may be at risk, their location, work activities and any disabilities that may present an increased risk. These would include: • Employees • Visitors / Members of the Public • Contractors • Fire Fighters Fire Risk Assessment Evaluate, remove, reduce and protect from risk. Once hazards and people at risk have been identified, evaluation of the risks needs to be undertaken. We should look at likelihood of fuels being present, being ignited by an ignition source and additional sources of oxygen that may increase speed and spread of fire. Any large spaces that may not be fire stopped may also affect a fire. Qualitative and Quantitative methods may be used to rate risk, although in most cases it is the former. It is normally based on a set of pre-determined questions (a fire risk assessment form) and allows the assessor to make a judgement on the risks being high, normal or low. Once an evaluation of risk has been undertaken, the business will need to consider ways of removing, reducing and protecting buildings and people using the principles of prevention which is specified in Part 3, Schedule 1 of the RRFSO. Fire Risk Assessment Reduce Sources of Ignition • Removing unnecessary sources of ignition, replacing with safer alternatives, using heat producing equipment in accordance with manufacturer’s instructions and is properly maintained. • Installing machinery and equipment designed to minimise risk of fire and explosions. • Replacing naked flame and radiant heaters with convector heaters of central heating. • Ensuring all fuses and circuit breakers are of the correct ratings and suitable for purpose. • Ensuring sources of ignition do not arise from overheated or overloaded equipment. • Operate a permit to work system for items like hot work such as welding or flame cutting. • Operate a safe smoking policy. • Prohibit matches or lighters in areas of high risk. • Ensure any equipment when not in use, is left in a safe condition. • Taking precautions again the risk of arson.
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Fire Risk Assessment Reduce Sources of Fuel • Removing flammable materials and substances, or reducing them to minimum required. • Replacing with less flammable alternatives. • Ensuring flammable materials are handled, transported, stored and used properly. • Ensuring adequate separation distances between flammable materials. • Storing flammable materials in fire resistant stores, and keeping minimum quantities in fire resisting cabinets in workroom. • Replacing or repairing upholstery. • Ensuring flammable waste materials are not allowed to build up and removed on a regular basis. • Taking action to avoid storage areas that are vulnerable to arson. • Ensuring good housekeeping. • Improving fire resistance in the construction of the workplace. Means of Escape • How long will it take for all the occupants to escape to a place of safety? • Is it a reasonable length of time or too long? • Are there enough exits and are they in the right place? • Are the type and size of exits suitable and sufficient for the number of people likely to need to use them (e. g. wheelchair users)? • In the event of a fire, could all exit be affected or a route remain available? • Are all escape routes easily identifiable, free from obstruction and adequately illuminated? • Have staff been trained in using the means of escape? Fire Detection and Fire Warning • Can existing means of detection discover a fire quickly enough to raise an alarm? • Can means of giving warnings be cleared heard and understood through the premises when initiated from a single point? • If the fire detection system is electronically powered, does it have a back up power supply? • Are employees aware of the system and will they know how to operate and respond to it? Fire Risk Assessment Reduce Sources of Oxygen • Close all doors, windows and other openings not required for ventilation. • Shutting down ventilation systems which are not essential to the function of the business. • Not storing oxidising materials near or with any heat source or flammable materials. • Controlling the use of oxygen cylinders making sure they don’t leak or used to ‘sweeten’ the atmosphere and their location adequately ventilated. Reduce Unsatisfactory Structural Features • Removing, covering or treating large areas of flammable wall and ceiling linings to reduce fire spread. • Ensure good fire stopping techniques are used for openings. • Good fire resisting structural materials are used and maintained. Means of Fighting Fire You need to have enough fire-fighting equipment in place for your employees to use either of the below without exposure to unnecessary risk? Aid means of escape To extinguish a fire in its early stage. • Are extinguishers suitable for the purpose and of sufficient capacity? • Are there sufficient numbers sited throughout the building? • Are the right types located close to the fire hazards and can users gain access to them without exposing themselves to risk? • Are the locations of the extinguishers obvious or does their position need indicating? • Have the people been given adequate training and instruction? Fire Procedures and Training • Do you have an emergency plan? • Does the plan take into account all reasonably foreseeable risks? • Are your employees familiar with the plan, trained and involved in testing it? • Is the emergency plan available to all who need to be aware of it? • Are the procedures to be followed clearly indicated throughout the building? • Has consideration been given to all likely people in the workplace, such as visitors, members of the public and those whom you may share with. It is also important that the assessor also considers measures already in place and recommend improvements where appropriate to help reduce risks further. Areas for consideration are given on the following cards.
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Fire Risk Assessment Maintenance and Testing • Do you regularly check all fire doors and escape routes and associated lighting and signs? • Do you regularly check your fire fighting equipment? • Do you regularly check your fire detection and alarm equipment? • Are those who test and maintain the equipment properly trained to do so? Record your Significant Findings Where you employ five or more employees or if an alterations notice is in force you must record the significant findings of your risk assessment in writing or some other retrievable means. A number of forms and systems have been designed for recording but they should all follow the same methodology. Significant Hazards People / Groups who are at risk Existing controls and risks not adequately controlled. Further action needed, by when, and who? Risk Assessment in Respect of Dangerous Substances Dangerous substances within a workplace may give rise to the risk of fire or explosion. It is important that a risk assessment has been carried out to identify risks that may be present. Dangerous Substances can include those defined as: • Extremely flammable • Highly flammable • Explosive • Oxidisers In determining level of risk, assessors should consider flashpoints, firepoint an auto ignition temperatures, upper and lower explosive limits and where it is being used, in what form, how it is stored any existing control measures. Having established the risks, new or further control measures should be considered and these could include for small quantities in the workplace when being stored and used. Risk Assessment in Respect of Dangerous Substances Fire Risk Assessment Reviewing / Revising the assessment Sooner or later you may introduce changes in your workplace which have an effect on your fire risks and precautions such as changes to the work processes, furniture, plant, machinery, substances, buildings or the number of people. Any of these could lead to new hazards or increased risk. So if there is a significant change, you will need to review your risk assessment. It is not necessary to amend the RA for trivial changes, but if a job introduces significant new hazards, these will need to be considered. In any case, the assessment should be reviewed regularly to ensure measures are still effective. Storage • Ventilation – is there plenty of fresh air to allow the safe dispersal of any vapours given off by accidental spillage, release or leakage. It is possible to store them outside of the workroom in open air? If stored inside, the area should be well ventilated either be natural or mechanical means. Permanent means such as using air bricks could be installed both at high and low levels. Five air changes per hour are normally enough to ensure vapour levels are kept low. • Ignition – sources of ignition should be excluded from the area wherever substances are to be stored. If using mechanical ventilation, the electrical safety of the system should be considered. • Containment – containers should be suitable for purpose and could include metal construction fitted with self closing lids to prevent spillage and vapour escape. Containers should be clearly labelled with information on the contents. Empty containers should be treated as full unless purged. • Exchange – can a less flammable material be used? Or eliminate storage and have a just in time delivery system? • Separation – are dangerous substances stored away from work area and other processes by physical means such as partitioning. If not possible, can flameproof storage be used that is secure and bunded? Incompatible substances should also be kept separate, out of direct sunlight, storing minimum quantities and not exceeding 50 litres inside.
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Fire Risk Assessment Use and Handling Where substances are used it is important to ensure adequate precautions are in place. Some measures such as elimination / control of ignition sources will be needed, but additional measures should include. Dispensing and Decanting – this should be done in a way to minimise spillages and releases of the liquids. If possible, an enclosed transfer system should be used or containers designed for the task used. Small containers are available which incorporate the following design features: • Heavy duty plastic or metal in construction • Apertures fitted with self closing lids with flame arrestors. • Hoses and other attachments for dispensing into small openings. • Carrying handles for larger capacity containers. It may also be necessary to maximise the use of funnels and spill trays to decant from sources of ignition. Fire Risk Assessment Where hot work is carried out on vessels (i. e. pipe work or petrol tanks that may contain residues of flammable liquids), this should only be done under a PTW system and no work should commence until the vessel has been cleaned. Smoking should be prohibited in areas where dangerous substances are used and signage posted accordingly. Housekeeping – good standards of housekeeping should be maintained throughout areas and this will involve: • Placing contaminated rags in suitable receptacles (e. g. metal lidded bins that are emptied regularly). • Dealing with spillages promptly using appropriate spill kits (absorbent mats or granules). • Containment of larger spills • Ensuring spillages do not enter drainage systems. Personal Protective Equipment – the use of flame proof overalls to protect the employee from splashes and spillages and possible subsequent ignition. Employees should be made aware through information, instruction and training on what to do in regards to spillages. Environmental Impact of Fire has a number of consequences and one area that many organisations tend to overlook is the effect of fire on the surrounding environment. Whilst the RRFSO does not specifically mention the environment, it does require the responsible person to ‘mitigate the effects of fire’. It would also be prudent to consider any applicable environmental or health and safety legislation when dealing with this. • The Water Resources Act 1991 – deals with the extraction of water from boreholes and rivers for which a license would normally be required except where the water is required for fire fighting purposes. • Control of Major Accidents Hazards (COMAH) Regulations 2005 – which exists to ensure businesses take all measures necessary to prevent major accidents and to limit the effects and consequences on people and the environment. The responsible person may be held liable to prosecution if robust fire prevention measures are not in place. Environmental Impact of Fire Sources of Pollution Fires in businesses can have a significant effect on the environment which threaten both water supplies and general public health. Some products are more obvious such as oils and chemicals, but some are less obvious and may only be a pollutant to the environment such as food or drink products. It is possible these products may escape from site into the water system such as: • Direct run off into watercourses or direct into the ground. • Into foul drainage, possible affecting stability of sewage treatment works. • Atmospheric pollution through vapour clouds. • Surface water drainage systems. Toxic Gases When various products such as plastics, foams etc are burnt, depending on their make up numerous toxic gases may be expected (carbon monoxide, carbon dioxide, hydrogen cyanide etc). All these gases are toxic, some in small quantities and can be harmful to the environment as well as people.
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Environmental Impact of Fire Smoke and its by-products can be extremely corrosive and is capable of causing long term damage to buildings and materials unless cleaned thoroughly after a fire. Consideration needs to be given to possible air pollution and gaseous product and companies should be able to identify: • What toxic chemicals are likely to be released • The prevailing wind conditions • The vicinity of neighbouring properties • Communication methods to the local communities • Type of smoke potentially and likely environmental damage. It is usual for the Environment Agency to work with the fire and rescue service if environmental impact is likely. The EA will normally give advice to the fire service unless there is strong operational safety reasons for not take the advice, the fire service would use the advice given. Environmental Damage For companies to determine whether they are at risk they should carry out an environmental risk assessment and should consider: • Possible materials and chemicals on site that may act as pollutants. • Location of surface water drains. • Natural / man made water courses including rivers, streams, lakes and ponds. • Existing containment strategies by bunding and tanks. • Shut off valves and ease of location to negate damage. • Interceptors to protect sewers in the event of foam use for fire fighting. • Secondary containment measures i. e. reservoirs for contaminated fire water. If risks have been identified, companies need to consider reducing the risk to an acceptable level, and the hierarchy below can be used: • Prevention – prevent the outbreak of fire by segregating / controlling sources of ignition for combustible materials, good stock control. • Detection – Installing and maintaining automatic detection and protection systems. • Containment – Installing and maintaining facilities for the containment of firewater for example, storage lagoons, chambers, isolation tanks and shut off valves. • Mitigation – planning in conjunction with local fire and rescue service for suitable fire fighting strategies including, recycling firewater where non hazardous, controlled burns where little or no water is used. Environmental Impact of Fire Reducing the Impact of Environmental Damage Environmental damage may be short and long term in terms of groundwater contamination which can persist for tens or hundreds of years. The resulting legal proceedings and clean up can be very costly. Not all industries would give rise to pollution even though hazardous materials may be present. The reason for this being that for there to be a risk of pollution, three components have to be present: A SOURCE e. g. contaminated fire water run off, toxic smoke A PATHWAY e. g. surface drains, permeable ground A RECEPTOR e. g. a river, groundwater, people If any one of the above components are missing then there can be no environmental risk. Environmental Impact of Fire water run off Water is the most widely used medium for fires as it is cheap, plentiful and effective. It also has the advantage that is it non hazardous. Most water run off generated in a fire is not usually an problem. If hazardous chemicals are involved, foam may be used instead, although water may still be used for it’s cooling effect. It can cause large amounts of pollution and there are ways this can be controlled: Bunding – it is sensible to store chemicals in bunded areas where the capacity of the bund would take the entire inventory of chemicals, plus the foam or water used to extinguish them. Particular attention should be paid to the ability of the bund walls to withstand the pressure from the contained liquids under fire conditions. Lagoons and tanks – permanent provision for the containment of large quantities of fire water run off, typically several thousand cubic metres and generally are remote and serve several storage areas. Sacrificial areas – might be natural depressions or specially created areas designed to have inherent containment provision. Separators – provide a specified design performance for removal of non-miscible hydrocarbons from the water allow discharge. Booms – can be used to provide total containment or used as flotation devices to contain lighter nonwater-miscible hydrocarbons. Drain seals – to cover or block a drain as an emergency containment system.
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