ASTM E1137/E1137M-08(2014)

1.1 This specification covers the requirements for metal-sheathed industrial platinum resistance thermometers (PRT's) suitable for direct immersion temperature measurement. It applies to PRT's with an average temperature coefficient of resistance between 0 and 100°C of 0.385 %/°C and nominal resistance at 0°C of 100 Ω or other specified value. This specification covers PRT's suitable for all or part of the temperature range −200 to 650°C. The resistance-temperature relationship and tolerances are specified as well as physical, performance, and testing requirements.