Laserfiche WebLink
fl <br />�1 <br />n <br />n <br />fl <br />Method 102 Revision I <br />6.2 The calibration factor (CF) is calculated during cal- <br />bration by the equation, <br />CF = cone <br />Area <br />1 6.3 <br />I � <br />H <br />fl <br />k <br />11 <br />L <br />I <br />k <br />P <br />L <br />L <br />The replicate calibrations are averaged and the arithmetic <br />mean is stored as the CF to be used in subsequent analyses. <br />Concentrations may be converted from ppb to ug/m 3 by <br />using the following formula: <br />uglm 3 = (P) x (MW) x (ppb) x (10 3 <br />(82.05) <br />where: P = pressure in atmospheres <br />MW = molecular weight of benzene, <br />78.11 g/mole <br />82.05 = gas constant, cm3_ x atm <br />mo t <br />T = absolute temperature, degK <br />7 Quality Control <br />7.1 Quality control procedures are managed in two areas: <br />sampling and analysis. <br />7.2 The sampling procedures use the following protocol: <br />7.2.1 The Tedlar bag samplers are checked every six months <br />for leakage and contamination. The interval is <br />shortened if any malfunction is suspected. A written <br />record is maintained of the history of each sampler. <br />(See Appendix A). <br />7.2.2 The Tedlar bags are checked for leakage and con'.-.arriina- <br />tion before being used for sampling. A log book is <br />maintained with a complete history of bag usage. <br />(See Appendix B). <br />7.3 The analytical procedures use the following protocol: <br />7.3.1 Calibrations are performed periodically. Acci!racy of the <br />method cannot be determined without an accept—I standard <br />reference materil and independent accuracy <br />evaluation. <br />7.3.1.1 An NBS Traceable reference material of 0.25 ppm (parts <br />per million) benzene in nitrogen is used to monitor <br />.5 <br />