API MPMS 3.1B

Abstract

This standard covers level measurement of liquid hydrocarbons in stationary, aboveground, atmospheric storage tanks using automatic tank gauges (ATGs). The standard discusses automatic tank gauging in general, accuracy, installation, commissioning, calibration and veri&#222;cation of ATGs that measure either innage or ullage. It covers both intrusive and non-intrusive ATGs used for either custody transfer or inventory control. The standard also covers the requirements for data collection, transmission and receiving. This standard does not cover the following: <br>a. Hydrocarbons having a Reid vapor pressure above 15 pounds per square inch absolute (100 kPa). <br>b. Measurement of weight or mass with ATG equipment. This is covered in Chapter 3.6 and Chapter 16.2 of the <em>Manual of Petroleum Measurement Standards .</em> <br>c. Measurement of level in underground tanks or in pressurized tanks storing liquid hydrocarbons. <br>d. Conversion of tank level to liquid volume. This is covered in Chapter 12.1 of the <em>Manual of Petroleum Measurement Standards .</em> <br>e. Measurement of temperature, sampling, density and sediment and water (S & W), which are discussed in Chapters 7&#208; 10 of the <em>Manual of Petroleum Measurement Standards</em> . <br>Safety and material compatibility precautions should be taken when using ATG equipment. Manufacturers&#213; recommendations on the use and installation of the equipment should be followed. Users should comply with all applicable codes and regulations, API Standards and NFPA 70 <em>National Electric Code .</em>