scope:

This Defence Standard (Def Stan) covers general purpose thermometers, special thermometers and thermometer pockets applicable to specific applications. 

The thermometers cover the requirements for temperature measurement in the Celsius Scales and, for legacy equipment, in Fahrenheit Scales. Where British Standards are quoted in this Def Stan it should be noted that they refer to the Celsius Scales only. These thermometers are generally suitable for use with the following:

Air Systems;

Battery Acid;

Boiler Feed Water Systems;

Fuel Oil Systems;

Lubricating Oil (LO) Systems;

Refrigeration Systems;

Steam Systems. 

The standard range of thermometer pockets for use with general purpose thermometers is included in this Def Stan. The relevant NATO Stock Numbers (NSN) are listed in the Figures.