【国外标准】 Standard Practice for Sampling of Liquids in Waste Management Activities Using a Peristaltic Pump

5.1 This practice can be used in sampling drums, tanks, and similar containers and in sampling monitoring and waste wells including small-diameter (2.5 cm (1 in.)) wells. The pump can collect samples from multiple depths. The samples can be high-viscosity fluids, aggressive and corrosive fluids, high-purity solutions, and abrasive fluids. The pump can be used to mix samples (see Guide D6063).5.2 Peristaltic pumps use a vacuum to transport the samples. This vacuum may cause some degassing and loss of volatile organic compounds (VOCs) from the sample. When precise quantitative data for VOCs and dissolved gases are not required, peristaltic pumps may be used.5.3 The pump is self-priming, runs dry without damage, and is completely isolated from the pumped fluid. A sample can be taken on the intake or discharge side of the pump.5.4 Some additional advantages of the peristaltic pump are: decontamination of the pump motor is not necessary and the tubing in the pump is disposable and easy to replace. The pumps can be easily started and stopped and can pump fluids at a wide range of pressures and flow rates.5.5 The place, quality and quantity, frequency, and time of sampling are dependent upon the decisions that are to be made (see Practice D6250), sampling design (see Guide D6311), the sample, the heterogeneity of the samples (see Guide D5956), how representative the sample is (see Guide D6044), and the parameters to be tested as determined by the data quality objectives (DQOs) (see Practice D5792).1.1 This practice covers the use of a peristaltic pump for sampling liquids from multiple depths. It is applicable for a wide range of fluids including: high-viscosity fluids, aggressive and corrosive fluids, high-purity solutions, and abrasive fluids. It is especially useful for sampling liquids that require complete isolation from the pump.1.2 This practice includes the determination of sample depth, pump setup, and collecting a sample to be analyzed.1.3 This practice is not intended to give detailed instructions for running a peristaltic pump or to recommend which peristaltic pump to purchase. It instructs the field personnel how to connect the pump and collect a sample.1.4 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026. Reporting of test results in units other than SI shall not be regarded as nonconformance with this standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.