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3.0 Sampling Collection Method and Equipment <br /> 3.1 Sampling Method <br /> The sampling method for asbestos in ambient air is National Institute for Occupational Safety <br /> and Health (NIOSH) Method 7402, Asbestos by Transmission Electron Microscopy (TEM), <br /> NIOSH Manual of Analytical Methods, Fourth Edition, 2004. The samples will be collected <br /> over a nominal 8-hour period. <br /> The asbestos air sampling procedure consists of drawing a known low volume of air through a <br /> mixed cellulose ester (MCE) filter. The filter is then sent to the laboratory for analysis. Shaw <br /> has selected Asbestos TEM Laboratories, Inc. (ATEM) as the laboratory for analysis under this <br /> project. ATEM is an accredited analytical laboratory for TEM analysis. NIOSH Method 7402 <br /> (direct method) will be used for determining the concentrations of asbestos in air. <br /> 3.2 Sampling Equipment <br /> The following table presents the monitoring equipment that will be installed at each station. <br /> Description of Proposed Equipment <br /> Equipmentlinstrument Manufacturer Specification <br /> Sampling Pump Gillian Thomas Pump Diaphragm Type <br /> Asbestos Filter MCE Filter Pore size 0.45 pm, with <br /> Cartridge TEM filter cassette <br /> pm =micrometer <br /> The sampling equipment consists of a sampling pump, filter cassette, connecting tubing, and a <br /> rotameter. The filter will be a three-piece cassette 25 millimeters in diameter, with conductive <br /> extension cowls. The cassette will be loaded with an MCE filter of 0.45 µm pore size. The filter <br /> will be backed by a 5 µm pore size MCE filter. A sample rate of 1 to 4 liters per minute for a <br /> duration of 8 hours will be maintained. <br /> 3.3 Equipment Calibration <br /> The sampling pump will be calibrated immediately before and after each run. Preliminary <br /> calibration should be conducted using a primary calibrator such as a soap bubble-type calibrator, <br /> with a representative filter cassette (from the same cassette lot as the sample cassettes). Three <br /> separate constant flow calibration readings will be obtained both before and after sampling. <br /> Should the flow rate change by more than 5 percent during the sampling period, the average of <br /> the pre- and post-calibration rates will be used to calculate the total sample volume. <br /> rmo�oua 3-1 <br />