VERIFICATION/CERTIFICATION OF DEVICES USED IN LIQUID MEASUREMENT and IMPLICATIONS OF HOW MERCURY ISSUES WILL IMPACT THESE PROCESSES

摘要

In the past the standards from the American Petroleum Institute (API) and the American Society for Testing and Measurement (ASTM) provided specifications for instruments and equipment. Simple compliance with these standards was not enough. Therefore, a system of verification and/or certification of equipment used in measurement of liquids was instituted. These requirements were written into the standards as they came up for review. An excellent example of such a standard is Chapter 3.1.A. 'Standard Practice for the Manual Gauging of Petroleum and Petroleum Products' of the API's Manual of Petroleum Measurement. 3.1.A. calls for field verification of working tapes against against a National Institute of Standards and Technology traceable master tape when it is new and every year thereafter. This is an example of the requirements to insure the instrument and the equipment meets the specifications of each standard. It is important to understand the definitions of traceability, verification, and certification before discussing the specifications for equipment used in liquid measurement.