Chain of custody form for indoor air quality survey at

NYC 9/11 Public Portal Document

CA RICH CONSULTANTS, INC.

I Typically, for indoor air quality in commercial office buildings, the Occupational Safety and Health Administration's (OSHA) permissible exposure limits (PELs) divided by a safety factor of 10 are

I applied. Based upon this guidance, and in reviewing comparisons with the ambient outdoor ground and rooftop concentration levels, we can conclude that the indoor air quality in the tested building spaces was found to be within acceptable parameters - as defined by ASHRAE guidelines for acceptable indoor air quality.

I The asbestos air sample results were compared to the Environmental Protection Agency's (EPA) Asbestos Hazard Emergency Response Act (AHERA) regulation of 70 structures per square millimeter (s/mm2). All of the indoor and outdoor asbestos samples that were taken during this Survey were found to be far below this level.

CONCLUSION

I Given the results of this air quality sampling survey and the relatively comprehensive suite of

I tested parameters, the air quality represented at each of the tested sites was relatively good and did not contain elevated contaminant levels, when compared to EPA's prevailing AHERA and OSHA air quality guidelines. They are also below the ASHRAE indoor air quality guidelines.

Although a few select volatile organic compounds and an occasional detection of carbon

I monoxide was noted in the air at the tested Buildings, these levels are not significant and would not qualify as "contamination" or necessarily require any further response at this time given ' applicable regulatory guidelines.

This Survey was performed diligently in consideration of the accepted practices of the environmental consulting profession. The undersigned cannot be held responsible for innocent or intentional misrepresentations or inaccurate statements, or limitations to work scope, schedule, claims, parameter source terms, or building occupation or activity, and/or information furnished to CA RICH that may or may not have influenced or impacted the technical approach

1 and air quality testing results reported herein. However, we do acknowledge that to the best of our belief, the information we have supplied is true, complete and correct, and that facts or figures that may have an adverse effect upon the validity of the findings and conclusions I developed from this Survey have not purposely been omitted.

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