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3.0 Sampling Collection Method and Equipment <br />• •, <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 <br />Manufacturer <br />Specification <br />Sampling Pump <br />Gillian Thomas Pump <br />Diaphragm Type <br />Asbestos Filter <br />Cartridge <br />MCE Filter <br />Pore size 0.45 Nm, with <br />TEM filter cassette <br />um = 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 />rn�azss 3-1 <br />