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o Contribuition to risk of various asbestos dust ievels c
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o Risk = Conc(f/cc) * TWF * Slope factor o
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o TWF is weighting factor for partial exposure (less than 70 years, 24 hrs a day) 03
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Slope factor of 0.23 f/cc used over a 70 year exposure O
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Low Fiber loading 1000 f/cm2 3
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Scenario Activity loading K factor Air level Years days/year hours/day TWF Contribution to Risk 3
DEP internal memo circulating draft EPA screening level standards for asbestos, fiberglass, and silica in indoor air and settled dust for agency comment.
EPA memorandum on wipe sampling methods for asbestos in Lower Manhattan buildings, resuspension projections, and cancer risk estimates from WTC dust exposure.