Screening levels asbestos fiberglass silica air dust, Apr 2002

NYC 9/11 Public Portal Document

Avaitroni, Robert HO' o Bi . ........... Ill From: Gilsenan, Michael Sent: Monday, April 01, 2002 3:04 PM To: Radhakrishnan, Krish; Theodorellys, Penny Cc: Avaitroni, Robert; Chapin, Diana 001; Sturcken, Charles 001 Subject: FW: draft screening levels for asbestos, FG and silica in indoor air and settled dust

Krish- pls. comment on attached. I think we need to explain to Diana what this means to Asbestos in the greater scheme of things, assuming EPA makes these the standards.! don't know if EPA could establish standards(benchmarks) for WTC only.

—Original Message— From: DeVoney, Danielle [mailto:[email protected] ] Sent: Monday, April 01, 2002 1:48 PM To: DeVoney, Danielle; '[email protected]'; '[email protected]'; '[email protected]'; Rodenbeck, Sven; '[email protected]'; '[email protected]'; '[email protected]'; '[email protected]'; '[email protected]'; '[email protected]'; '[email protected]'; '[email protected]'; 'Randi J. Walker'; 'Patricia M. Fritz' Cc: '[email protected]'; '[email protected]'; '[email protected]'; Cooper, Barbara; Lee, Carolyn V. (Virginia); Neurath, Sue; Wilder, Lynn Subject: RE: draft screening levels for asbestos, FG and silica in indoor air and settled dust

Hi-

I ran some quick calculations for risk combining air and dust numbers, and integrated them into a screening level table, this assumes protecting for a 1/10,000 risk for one year for the upper tier, and the same for 30 years in the lower tier.

This is a first attempt on risk number, different exposure assumptions, and K values would yield slightly different results. I'm providing this as a basis for discussion. If we like the approach we can refine the risk calculations appropriately. Also, I've used a K factor of 1 x 10 -7 for "daily activity" - although this works well with the math, we may want to refine that number also.

thanks, danieile

—Original Message— From: DeVoney, Danielle Sent: Monday, April 01,200211:58 AM To: '[email protected]'; [email protected];

NYC-WTC_000160806