The purpose of this paper is to explain the measurement of natural gas for custody transfer applications through the
use of ultrasonic meters. Specifically, this paper explains the operation of ultrasonic meters, issues surrounding their
performance in natural gas, calibration procedures, and proper installation considerations. Additionally, the
electronics making the measurements generate calculated values relating to the operation of the meter and as a result
a database is available to provide analysis of the meter’s ongoing performance. Meter health parameters can be
evaluated to verify the meter’s operation and these principles are explained.