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Nuclear Energy Safety Operation, Accidents, Attacks, and Proliferation Kallie Metzger
Health Concerns Radiation Poisoning
Radiation Poisoning Large dose of radiation in a short amount of time OR Low level exposure for a long period of time. Symptoms occur because it makes you feel nauseas and radiation interferes with cell division A cell incident to radiation can: Divide as planned and remain unaffected Die- (This is why radiation is used in cancer treatment!) Or divide incorrectly If this is the case, as the mutated cells regenerate they create more and more mutated cells=cancer
Continued… How exposure is measured: Rad- 0. 01 Joules of energy per kilogram of tissue. (Gy)- 1 joule per kilogram of tissue thus, 100 rad=1 Gy In order to determine the effect of the dose on the tissue, you must first know the specific radiation type’s affect on tissue, or relative biological effectiveness (RBE), which you multiply by the dose to determine the overall effect, given in units of Seiverts (100 rem=1 Sv) The RBE is given in units of Röntgen-or rems and is called a quality factor and therefore denoted by Q. Alpha-Q may be as high as 20 Neutron radiation- depends on their energy. Beta particles, x-rays, and gamma rays- Q=1
Levels of Exposure: 0. 05– 0. 2 Sv (5– 20 REM) No symptoms---may be beneficial? (hormesis) 50 m. Sv is the yearly federal limit for radiation workers in the United States. In the UK the yearly limit for a classified radiation worker is 20 m. Sv. 0. 2– 0. 5 Sv (20– 50 REM) No noticeable symptoms. Red blood cell count decreases temporarily. 0. 5– 1 Sv (50– 100 REM) Mild radiation sickness with headache and increased risk of infection due to disruption of immunity cells. Temporary male sterility is possible
Continued… 1– 2 Sv (100– 200 REM)Light radiation poisoning, 10% fatality after 30 days Typical symptoms include mild to moderate nausea (50% probability at 2 Sv), with occasional vomiting, beginning 3 - 6 hrs after exposure and lasting for up a day. Followed by a 10 to 14 day dormant phase, after which light symptoms like general illness and fatigue appear because immune system depressed. Temporary male sterility is common. Spontaneous abortion or stillbirth will occur in pregnant women. 2– 3 Sv (200– 300 REM)Moderate radiation poisoning, 35% fatality after 30 days Nausea is common (100% ), with 50% risk of vomiting symptoms onset at 1 to 6 hours after irradiation and last for 1 to 2 days. 7 to 14 day latent phase, after which the following symptoms appear: loss of hair all over the body (50% probability), fatigue and general illness. Massive loss of white blood cells, greatly increasing the risk of infection. Permanent female sterility is possible. 3– 4 Sv (300– 400 REM)Severe radiation poisoning, 50% fatality after 30 days Symptoms are similar to the 2– 3 Sv dose with uncontrollable bleeding in the mouth, under the skin and in the kidneys after the latent phase.
It gets worse… 4– 6 Sv (400– 600 REM)Acute radiation poisoning, 60% fatality after 30 days Fatality increases from 60% at 4. 5 Sv to 90% at 6 Sv (unless there is intense medical care) Symptoms start 30 min. - 2 hrs after exposure and last up to 2 days. 7 to 14 day latent phase, after which generally the same symptoms appear as with 3 -4 Sv irradiation, with increased intensity. Female sterility is common at this point. The primary causes of death (in general 2 to 12 weeks after irradiation) are infections and internal bleeding. 6– 10 Sv (600– 1, 000 REM)Acute radiation poisoning, near 100% fatality after 14 days. Survival depends on intense medical care. Bone marrow is nearly or completely destroyed (bone marrow transplant required) Gastric and intestinal tissue are severely damaged. Symptoms start 15 to 30 minutes after irradiation and last up to 2 days. -Latent phase-death Recovery would take several years and probably would never be complete.
Even Worse… 10– 50 Sv (1, 000– 5, 000 REM)Acute radiation poisoning, 100% fatality after 7 days An exposure this high leads to spontaneous symptoms after 5 to 30 minutes. powerful fatigue and immediate nausea caused by direct activation of chemical receptors in the brain by the irradiation there is a period of several days of comparative well-beinglatent phase- After that, cell death in the gastric and intestinal tissue, causing massive diarrhea, intestinal bleeding and loss of water/ This leads to water-electrolyte imbalance. Death sets in with delirium and coma due to breakdown of circulation. Death is inevitable; only treatment is pain therapy. More than 50 Sv (>5, 000 REM) death an operator receiving between 60 and 180 Sv (18, 000 REM) to his upper body in an accident at Los Alamos, New Mexico, USA on in December 1958, survived for 36 hours 10 -20 Gy
So, with all the risks…we need regulations…
Agencies Internationally -International Atomic Energy Agency (IAEA) U. S. - Civilian nuclear safety is regulated by the Nuclear Regulatory Commission (NRC). BUT the safety of nuclear plants and materials controlled by the U. S. government for research, weapons production, and those powering naval vessels, is not governed by the NRC. UK -Nuclear safety is regulated by the Nuclear Installations Inspectorate (NII) and the Defense Nuclear Safety Regulator (DNSR).
International Atomic Energy Agency (IAEA) Est. in 1957 as the world’s “Atoms for Peace” program Promote peaceful use of nuclear energy and inhibit use for military purposes Est. the International Nuclear Events Scale 144 member states In terms of safety and security, they oversee nuclear installations, radioactive sources, radioactive materials in transport, and radioactive waste. “A core element is setting and promoting the application of international safety standards for the management and regulation of activities involving nuclear and radioactive materials. ”-IAEA “The focus is on helping States prevent, detect, and respond to terrorist or other malicious acts - such as illegal possession, use, transfer, and trafficking - and to protect nuclear installations and transport against sabotage. ”- IAEA
Nuclear Regulatory Commission (NRC) Created in 1974 Regulates commercial nuclear power plants and other uses of nuclear materials, such as in nuclear medicine, through licensing, inspection and enforcement of requirements. Their program establishes limits for radiation exposure for workers and the general public and requires that those using nuclear material take steps to keep exposures well below the limits. If you want to use radioactive material, you must obtain a license. EXCEPT-in the case of very small amounts of radioactive materials -- like the tiny radiation source inside many smoke detectors. BUT the manufacturing of these and similar items, require specific licensing and regulatory control. Licenses: Commercial nuclear fuel facilities involved in the processing and fabrication of uranium ore. Licenses for other uses of radioactive materials are issued either by the NRC or by State Governments under NRC-approved programs. Construction permit operating license Individual personnel licenses- (Reactor Operator and Senior Reactor Operator)
International Nuclear Events Scale http: //www-ns. iaea. org/tech-areas/emergency/ines. htm
International Nuclear Events Scale (INES) Established by the IAEA Level 7 A large off-site impact, widespread health and environmental effects. Example: Chernobyl disaster (former Soviet Union) in Ukraine - 1986. Level 6 Significant off-site release, likely to require full implementation of planned countermeasures. Example: Mayak accident (former Soviet Union) - 1957. Level 5 Limited off-site release, likely to require partial implementation of planned countermeasure-example: Windscale fire (1957); or severe damage to a reactor core/radiological barriers- example: Three Mile Island accident (1979). Level 4 Minor off-site impact resulting in public exposure of the order of the prescribed limits, or significant damage to a reactor core/radiological barriers or the fatal exposure of a worker. Examples: Sellafield (UK) - 5 incidents 1955 to 1979, Saint-Laurent Nuclear Power Plant – 1980, Buenos Aires – 1983, and Tokaimura nuclear accident (Japan) - 1999. Level 3 A very small off-site impact, public exposure at levels below the prescribed limits, or severe spread of contamination on-site and/or acute health effects to one or more workers, or it is a "near accident" event, when no safety layers are remaining. Examples: THORP plant Sellafield (UK) – 2005 and Paks Nuclear Power Plant - 2003. Level 2 This is an incident with no off-site impact, a significant spread of contamination on-site may have occurred, or overexposure of a worker, or incidents with significant failures in safety provisions. Ex: Forsmark Nuclear Power Plant - Sweeden 2006 Level 1 This is an anomaly beyond the authorized operating regime.
Nuclear Reactor Accidents August 21, 1945 – Los Alamos National Laboratory, Los Alamos, New Mexico, USA – Accidental criticality Harry K. Daghlian, Jr. dropped a tungsten carbide brick onto a plutonium core, inadvertently creating a critical mass. Fatally radiated -Died 9/18/45. October 8– 12, 1957 – Sellafield, Cumbria, UK – Windscale Fire. Reactor core fire Technicians overheated Windscale Pile No. 1 because poorly placed temperature sensors indicated the reactor was cooling rather than heating. The excess heat lead to the failure of a nuclear cartridge. The resulting fire burned for days, damaging a significant portion of the reactor core. About 150 burning fuel cells could not be lifted from the core, but operators succeeded in removing nearby fuel cells. An effort to cool the graphite core with water eventually quenched the fire. The reactor had released radioactive gases into the surrounding countryside, primarily in the form of iodine-131. Milk distribution was banned in a 200 -square-mile area around the reactor for several weeks. Unlikely harm to humans. December 30, 1958 – Los Alamos, New Mexico, USA – Accidental criticality A critical mass of a plutonium solution was accidentally assembled. A crane operator died of acute radiation sickness. October 1988 – Rocky Flats in Colorado. At the nuclear trigger assembly facility at Rocky Flats in Colorado, two employees and a D. O. E. inspector inhaled radioactive particles, causing closure of the plant. Several safety violations were cited, including uncalibrated monitors, inadequate fire equipment, and groundwater contaminated with radioactivity.
A few more… June, 1999 - Shika Nuclear Power Plant- Ishikawa Prefecture, Japan- Control rod malfunction -INES Level needed Incident: Operators attempting to insert one control rod during an inspection neglected procedure and instead withdrew three causing a 15 minute uncontrolled sustained reaction at the number 1 reactor of Shika Nuclear Power Plant. Result: The Hokuriku Electric Company who owned the reactor did not report this incident and falsified records, covering it up until March, 2007. April 6, 1993 - Tomsk-7 Siberian Chemical Enterprise - Tomsk, Russia - Explosion -INES Level 4 Incident: Explosive mechanical failure in a reaction vessel. The explosion dislodged the concrete lid of the bunker and blew a large hole in the roof of the building. Result: The hole released approximately 6 GBq of Pu 239 and 30 TBq of various other radionuclides into the environment. The accident exposed 160 on-site workers and almost 2, 000 cleanup workers to total doses of up to 50 m. Sv (the threshold limit for radiation workers is 100 m. Sv per 5 years). September 30, 1999 – Reprocessing Facility in Tokaimura Japan- Accidental criticality INES Level 4 Incident: Workers put uranyl nitrate solution containing about 16. 6 kg of uranium, which exceeded the critical mass, into a precipitation tank. The tank was not designed to dissolve this type of solution and was not configured to preventual criticality. Result: Three workers were exposed to neutron radiation doses in excess of allowable limits. Two died.
Chernobyl April 26, 1986 –Chernobyl Nuclear Plant- Prypiat, Ukraine (then USSR) - Power excursion, explosion, complete meltdown- INES Level 7 Incident: An uncontrolled power excursion during a safety test caused a severe steam explosion, meltdown and release of radioactive material. Result: Approximately fifty fatalities resulted from the accident and many more cases of cancer. (mostly thyroid) The explosion and combustion of the graphite reactor core spread radioactive material over much of Europe. 100, 000 people were evacuated from the areas immediately surrounding Chernobyl in addition to 300, 000 from the areas of heavy fallout in Ukraine, Belarus and Russia. An "Exclusion Zone" was created surrounding the site encompassing approximately 1, 000 mi² (3, 000 km²) and deemed off-limits for human habitation for an indefinite period.
Recent Accidents April 10, 2003 - Paks Nuclear Reactor -Paks, Hungary -Fuel damaged - INES Level 3 Incident: fuel rods undergoing cleaning spilled fuel pellets the plant. Result: Boric acid was added to the tank to prevent the loose fuel pellets from achieving criticality. Ammonia and hydrazine were also added to absorb iodine-131. April 19, 2005 – Thorp Nuclear Fuel Reprocessing Plant- Sellafield, UK - Nuclear material leak -INES Level 3 Incident: 20 tons of uranium and 160 kilograms of plutonium dissolved within 83, 000 liters of nitric acid leaked from a cracked pipe over several months into a stainless steel “sump” chamber. Result: The partially processed spent fuel was drained into holding tanks outside the plant. November 2005 — Excelon’s Braidwood Station- - Braidwood, Illinois - INES Level needed -Nuclear material leak Incident: Tritium contamination of groundwater was discovered at Exelon's Braidwood station. Result: Groundwater off site remains within safe drinking standards though the NRC is requiring the plant to correct any problems related to the release. March 6, 2006 —Nuclear Fuel Services Erwin Plant- Erwin, Tennessee - Nuclear material leak- INES Level needed Incident: 35 liters of a highly enriched uranium solution leaked during transfer. Result: Seven-month shutdown and a required public hearing on the licensing of the plant. August, 2007 Clinton, Michigan- Theft of nuclear sources
Nuclear-Non Proliferation Treaty Signers: the five Nuclear Weapons States (NWS) recognized by the NPT: the People's Republic of China, France, Russian Federation, the UK, and the USA. Notable non-signers are Israel, Pakistan, and India (the latter two have since tested nuclear weapons, while Israel is considered by most to be an unacknowledged nuclear weapons state). North Korea was once a signatory but withdrew in January 2003. The legality of North Korea's withdrawal is debatable but as of October 9 th, 2006, North Korea clearly possesses the capability to make a nuclear explosive device.
Nuclear Proliferation Red- Five "nuclear weapons states" from the NPT Orange- other know nuclear powers Purple-formerly possessed nuclear weapons Blue- at one point had nuclear power Pink-possess just not widely adopted Lt. Orange- Suspected of having nuclear power
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