Chain of custody form for air monitoring, 365 South End

NYC 9/11 Public Portal Document

It any dust and/or debris was found in the apartment we laboratory for analysis. collected a bulk sample and sent it to the If no sample could be taken due to insufficient material apartment, the inspector documented present at the time we were this on the lo g. in the

4.' Air Sampling Procedures

ALC's licensed technicians collected air samples using TEM collected fi ve (S) air samples on each Methodology y threeThr technician floor. two separate areas in the hallways on each The samples were taken in Irtmc floor. The tech nician and at appeared to contain the most identified the i n that visible dust and debris to loci

perform sampling. The air sarnpies were collected using high volume air place the air sampling sampling pumps. Once the technician recorded the location, pumps were in flow rate, start and stop times time, date, sample and his initials. numbers, pump number,

The air cassette was independent of the pump motor From affecting the fi bers in the This is to prevent the cassette. A separate stand or vibrations of the motor place. The cassette was angled tripod was used to hold the 45 degrees downward cassette in that no asbestos will drop into from the horizontal stand. the cassette while This is to insure sampling. Using a rotameter, we calibrated each pump to the required flow sample record After calibrating rate, noting this rate on the pumps, the end cap the was turned on and run for the from the cassette was required amount of time removed; the pump

. The sampling_ pumps were p, checkedPeriodically to ensure they were still in place, and no one were still operat!ng, the has disturbed the equipment. cassettes was suspected of having high It at any time the area fiber counts, the filter inside being sampled overloading", or an excessive amount the cassettes were of fibers and/or debris on examined for the filter. When the DC determined volume of air has been sampling pump again to determine collected, the technician then the current flow rate. calibrated the flow rate measured at the This rate will often be beginning of the sampling period. different from the clogging of the fi lter, thereby adding That difference is usually increased resistance to the fl ow due to the of air. Once the pre -determined volume of air has been reached, cassette. Before the pump was the time was recorded as turned off, the cassette was angled well the and the end plug. The upward and the cap replaced cassettes were placed in sealed and a sample log was kept, containers, labeled with an The samples were then identifying code asbestos content. A chain of custody submitted to the laboratory to be record was prepared and analyzed for laboratory. accompanied the samples to the

4.3. Asbestos Analysis and Methodology Each air sample is cross-referenced by field designation { consistent handling through a and lab internal code to chain of custody. Sample ensure proper Filter clean bench to avoid any preparation takes place within a possible contamination. Air HEPA approximating the breathing zone of sampling was conducted at a level persons anticipated to be operations. Samples collected present in the area during represent the typical airborne fi normal ber concentration of the area.

NYC-WTC 000117727