《flowratemultipointsop》由会员分享，可在线阅读，更多相关《flowratemultipointsop（6页珍藏版）》请在金锄头文库上搜索。
1、Flow Rate Multipoint SOP PEPF-7.03 Date: 11/22/98 Revision 1 Page: 2 of 61.0 Scope and ApplicabilityNOTE: The following information is applicable to the BGI Model PQ200A portable FRM sampler when used with the BIOS DryCal primary flow rate standard. Specific information herein may not be applicable
2、to other makes and models of equipment.Each reference or Class I equivalent PM2.5 sampler includes a specially designed sample air inlet, a size fractionating impactor, and a sample flow rate control system. The particle size discrimination characteristics of both the inlet and the impactor are crit
3、ically dependent on specific internal air velocities; a change in velocity will result in a change in the distribution of the nominal particle sizes collected. These velocities are determined by the actual volumetric flow rate of the sampler.In addition, the total volume of air sampled is determined
4、 from the measured volumetric flow rate and the sampling time. The mass concentration of PM2.5 in the ambient air is computed as the total mass of collected particles in the PM2.5 size range divided by the total volume of air sampled.Therefore, in order to control the size-fractionating cutpoints an
5、d to measure the total volume correctly, the samplers flow rate must be maintained at a constant value that is within +5% of the design flow rate of 16.67 Lpm. The flow rate of the portable FRM sampler must be verified at each site before the PE sample is taken.This SOP should be employed only if ad
6、justments were made to barometric pressure (PEPF 7.01) and/or temperature (PEPF 7.02) or if the flow rate verification (PEPF 6.04) showed out-of-tolerance flow rate.2.0 Summary of MethodA multipoint flow rate verification/calibration of the sampler is performed once a year. After the multipoint cali
7、bration, the flow rate is verified with the Chinook Streamline TM FTS again to confirm that the +4% tolerance has been achieved.3.0 DefinitionsAppendix A contains a glossary of terms used in the PEP.4.0 Personnel QualificationsPersonnel who conduct the FRM PEs must have passed the written and the ha
8、nds-on practical training examinations for the field component in the PM2.5 FRM PEP.5.0 Cautions Do not operate the sampler without a flow verification filter installed. Calibration of the samplers flow rate measurement system must be in the units of the actual ambient volumetric flow rate. Do not u
9、se “mass flow rate“ or “flow rate at standard conditions.“FRM PEP Field SOP Section 7 PEPF-7.03 Date: 11/22/98 Revision 1 Page: 3 of 6 The portable FRM sampler must pass the verification check for external leaks before the flowverification/calibration is performed. Do not calibrate the flow rate mea
10、surement system if there is any doubt that the temperature andpressure measurement systems also are not in calibration. If there is doubt, verify/calibrate thetemperature and pressure sensors. Verify tight connections exist between the BIOS flow rate standard and the sampler. Thisincludes all o-ring
11、 seals and hose connections. When the equipment is not in use, cap all entrance points to the BIOS primary flow calibratorand store in a protective case or container. 6.0 Equipment A flow rate calibration adapter and tubing to connect the primary flow rate standard outlet to thePM2.5 sampler downtub
12、e. The BIOS Model DryCal DC-Lite piston flowmeter will be supplied for use in the FRM PEP. Chinook Engineering Streamline FTS Dwyer Series 475-0 Digital Manometer Flow Rate Multipoint Verification/Calibration Data Sheet.7.0 Procedure7.1 OverviewThe operating flow rate of 16.67 Lpm is verified before
13、 each PE. If the verification result is outside the required +5% tolerance for agreement with the design flow rate of 16.67 Lpm, a multipoint calibration at three different flow rates may be required. The one-point verification must be repeated after any threepoint calibration as a double-check to e
14、nsure the sampler operates properly at the design flow rate of 16.67 Lpm.Calibration of the samplers flow rate measurement system consists of three separate flow rate measurements (a multipoint calibration) approximately evenly spaced over the range of -10 % to +10 % of the samplers operational flow
15、 rate. Adjustments to the samplers pump speed are made through entries to the calibration screen keyboard so that the samplers indicated flow rates are brought into agreement with the flow rate as measured by the BIOS flow standard device.FRM PEP Field SOP Section 7 PEPF-7.03 Date:11/22/98 Revision
16、1 Page: 4 of 67.2 Multipoint Flow Rate Verification/CalibrationCAUTION: This procedure makes changes to the internal calibration of the FRM sampler. Do not proceed unless you are certain that verification/calibration is necessary. This calibration is best performed at an indoor location.The samplers flow rate measurement system is recalibrated using three separate flow rate measurements evenly spaced within the range of -10 % to +10 % of
