Assessment tools • A number of ‘approaches’ documented & available and being used/developed inhouse – e. g. 15 models/approaches participated within the IAEA EMRAS Biota Working group (although ranged from dose or transfer models through to more complete assessment tools) PROTECT FP 6 -036425
Assessment tools • Software for some tools freely available – including RESRAD-Biota (implementation of USDOE Graded Approach); ERICA Tool; England & Wales EA R&D 128 • Many approaches use a tiered assessment structure (in common with other areas of risk assessments) – simple initial screening through to more refined assessments PROTECT FP 6 -036425
Initial screening tier: Tier 1 • Designed to be simple and conservative – User only needs to input media activity concentrations • Aim - to enable sites of negligible concern to be identified and removed from need for further assessment – with a high degree of confidence • Envisaged that most sites will only need this level of assessment [i. e. ‘be screened out’] PROTECT FP 6 -036425
Tier 1 • Media concentrations are compared to predefined concentrations (EMCLs or BCGs) = concentration giving rise to screening dose rate (to most limiting organism) PROTECT FP 6 -036425
Tier 1 – conservative • Maximum measured or modelled media activity concentrations advised as input • Transfer parameters used to derive EMCL/BCG are maximums or 95 th percentiles • Habitat assumptions (e. g. RESRAD-Biota terrestrial animal surrounded by soil) • Dose conversion coefficients (RESRAD-Biota) progeny with half-lives <100 year included; external exposure organism assumed to be very small; internal exposure organisms assumed to be large) PROTECT FP 6 -036425
Higher tier assessments Use same dose rate USDOE graded approach PROTECT FP 6 -036425
Higher tier assessments ERICA PROTECT FP 6 -036425
PROTECT benchmarks & tiered assessments PROTECT benchmarks io ct ry a s vel( n le to la egu sc Ta re xo en n in om g le ic ve ls Middle level tiers (site specific/user defined inputs) ic xonom vels Ta ng le reeni c s ner Highest level tier (risk characterisation) RQ>1 R Ge ) ic s cre eni ng lev e RQ>1 l Initial screening tier (highly conservative) Assessment frameworks PROTECT FP 6 -036425
Скачать презентацию Assessment tools A number of approaches documented
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