Comments on aggressive indoor air sampling methods using leaf blowers,

NYC 9/11 Public Portal Document

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a. Based on consultation with resident or owner, aggressive or modified aggressive air sampling will be conducted. Residents shall not be present in their apartment during aggressive air sampling activities.

We do not see the benefit or need to use a leaf blower to aggitate die indoor environment to this extent during sampling. An electric leaf blower is capable of producting air velocities of 155 to 210 mph according to Sears. These air velocities are far removed from any air velocities that occiir m indoor environments. (And, yes, you can reduce the air velocities from a leal'blower to some extend, but what is the point?) We understand that such a technique was used mminers^abins in Montana but this is less than pursuasive-given the differences between those indoor oivifonments and those of occupied apartments in'Manhatten. Why would we do lhis? What is the benefit? We are ^t aware of any expert on indoor air quality who has used or would advocate the use of such higfi'air velocities. In addition, the fact that we propose that the resident or owner decide whether to use aggressive (leaf blower) of modified aggressive sampling protocols suggests thaTtfiTaggressiYe protocol is not core or key to our study. Moreover, it will S3*SofRer stratification to our study and reduce our power to interpret the study results. There is al^Wepo^tial to damage furnishings in the dwellings throug the use of this technique. It will onlytake aTewTu^Bly publicized incidence to tarnish our whol effort. We recommend that we do not propose theuseoTIBe aggressive sampling protocol.

1. Beforobeginning-^^^ssive a+r -^fnnpting,- Rtfeed-aif-cquipment (such as a-1 horsepower elective leafblower) shall bc-ased to-direet-exhaost-airagainst walls;■cciling^fers and ofrier sarfaees:-When directing the exhausf eaufien shaH-be-taken-to-nfi«ifni»e-dtstttfb|tnee-«id-p©terttal-d«nage-to-fitt«ishings Mid personal; bclongit^! 4tr For. modified aggressb PmplM^fofccd. Hir cqaipmcnt. shall. aot-be es hfThe terminology uscd here is incorrect and confusing because a 20-in fan is a fonn of forced air equipment. ■ ?n^eedotes arc identical for aggressiwand modified aggressive.air tphag: ■t b. Of elf: shall be installed per 10,000 cubic feet of room space and run at low 'P’ ifii tell operate continuously throughout sampling and shall not be turned off until sampling completed. How long before sampling should the fan be turned r on? This is m important issue because we want to sample at or near steady state tod the air moved by the fan has a time constant the will partially determine how long it will take to achieve steady state. At a minimum, the time prior to sampling when the fan should be turn on should be specified. c. For sttio apartments 3 air samples shall be collected. For 1 -bedroom apartments and above 5 air samples shall be collected. Sampling equipment shall be placed in living areas and away from obstructions. The sampling cassette must be placed on a tripod directed downward at a 45 degree angle and not taped to existing surfaces. d. Gommen spaces will be samplcd-without'the use- of forced air deviees-ffwsHeaf blowers ete). For small spaces, less than 160 square feet, 3 air samples will be collected. For large spaces greater than 160 square feet and less than 25,000 square feet 5 air samples will be collected. For spaces greater than 25,000 square feet, 1 mr

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