10.009 Curing Room Recording Thermometer

Q In ASTM C511-04, it talks about calibration of the recording thermometer, then continues to discuss how to perform verification of the recording thermometer. If the recording thermometer is calibrated every six months, what logic says we have to perform verification? This seems redundant. Can you give us a little insight of this logic?

Excerpt from Section 5.1, ASTM C511, Standard Specification for Mixing Rooms, Moist Cabinets, Moist Rooms, and Water Storage Tanks Used in the Testing of Hydraulic Cements and Concrete:

“The recording thermometer shall be calibrated at least every six months or whenever there is a question of accuracy.

Perform the verification of the recording thermometer by comparing the temperature reading of the recording thermometer with the temperature reading of a reference thermometer during the normal operation of the moist cabinet or moist room.

The thermometer used as the reference thermometer must be accurate and readable to 0.5°C.”

— Unknown

A 10/12/05 – Response prepared by Terry Egland, Principal, Testing Engineers, Inc., San Leandro

I posed this question to the ASTM staff member in charge of C511, who asked Mr. Ray Kolos of CCRL to respond. Mr. Kolos stated that the intent of the standard is that verification of the recording thermometer will be conducted every six months using a reference thermometer. Section 5.1 uses the term “calibrated” even though verification is intended. Mr. Kolos will ask the chairman of the ASTM Committee C1.95, Mr. Dave Norris, to consider modification to correct the error.