NYCDOH/ATSDR residential asbestos sampling results November-December 2001

z Z o o co § '2 o o 70 structures/mm" TEM • If < than 70 s/mm', no restrictions on access to buildings • If > 70 s/mm’, resample to confirm and analyze field blanks; take action to identify source and reduce levels to < 70 s/mm’ AHERA standards (40 CFR 763) NYC Clearance standard for • AHERA standards apply only to schools, and by NYC ordinance to buildings. • Method sensitivity and counting rules should follow Appendix A (Table 1) in AHERA 40 CFR 763; Method sensitivity based on # grids analyzed and air U c CT o' Ca3 buildings sample volume and must be maintained at 0.005 f/cc. U CD o O> 3. CD 03 Ca3 o o o c 3 CD

0.01-0.1 f/cc PCM/PCMe' • Continue to monitor, consider the need for additional Lowest limit set at 1/10 • Long-term exposures may increase cancer risk in the general public. sampling sites. PEL/REL/TLV; AHERA • Unlike workers the general population, includes children and sensitive persons, • If air levels are consistently between 0.01 to 0.1 f/cc, evaluate standards (40 CFR 763); does not receive exposure monitoring and does not participate in annual health the need for advisories, the need to limit ATSDR Toxicological Profile screening access and the need for dust suppression.. for Asbestos; IRIS; OSHA29CFR 1926.1101;

>0.1 f/cc PCM/PCMe’ • Evaluate the need to restrict general public access. Unacceptable cancer risk General public should not be exposed to levels suspected of adverse health effects • Continue to monitor; consider the need for additional following long-term exposure; upon long-term exposure. sampling sites.. AHERA standards (40 CFR 763); ATSDR Toxicological Profile for Asbestos; IRIS; OSHA29CFR 1926.1101

1. General public includes adults and children not directly involved in emergency response and recovery activities. 2. Documents and information that were considered in setting the action level. 3. Background levels for NYC are being determined. 4. PCM equivalents (PCMe) is determined using TEM analysis and counting fibers > 0.3 ^m in diameter and > 5 ^^m in length. PCMe should be determined using consistent methods to provide comparable concentrations. If PCM is exceeded, may need to determine PCMe using TEM. Use professional judgement to determine if PCMe is needed by evaluating the frequency and magnitude of exceedance, size of geographic area involved, and trends in data.

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