A simple and accurate formula for the sound velocity in water

The sound velocity in test objects and phantoms is often measured by performing a differential measurement with pure water. To promote standardization, a simple formula for the sound velocity in water is derived that renders true values within 0.20 m s(-1) over the temperature range 15-35 C. The formula is given by c = 1404.3 + 4.7 T - 0.04 T2, with sound velocity c in m s(-1) and temperature T in C.