Air level: Evaluate conditions in the For those areas where air
NYC area including levels would not warrant
background representativeness cf air removal of sensitive
- 0.01 f/cc * samples, fibrous glass dust individuals, but are above the
levels and loading. 0.001 f/cc, continued
Or cleaning and evaluation is
prudent.
Settled Dust If air samples were not
level: taken, then appropriate air Settled dust threshold is to
sampling should be protect to at least a IXIO"^
10,000 f/cm2 conducted to determine if risk estimate for a 30 year
To fiber levels are elevated. exposure. Air concentrations
100, fZcm estimated for different
2 Take actions to reduce activities using a K factors
exposures. based on Millette's work on
- clean area asbestos. Risk estimate is
- resample based on estimates of air
- ongoing cleaning levels, and duration of
exposure for different
activities. (10, 7cm2
corresponds to a 1x10-4 risk
for a 30 year exposure)
NYC-WTC_000140652
OCR can misread numbers and units. Confirm readings against the page image before using them.
NYC-WTC_000140652Source: NYC Law Department, mirrored locally
DEP internal memo circulating draft EPA screening level standards for asbestos, fiberglass, and silica in indoor air and settled dust for agency comment.
Introduction to a cross-agency group tasked with identifying contaminants of concern and establishing health-based screening levels for the indoor environment.