scope:

This standard is intended for users in industry in particular.

Radiation thermometers, also called pyrometers, with electronic means of data acquisition have reached a high level of development. Experience has shown that the long-term stability of industrially manufactured radiation thermometers is adequate under laboratory conditions. When these are used in industrial practise,

changes on the metrological properties can occur which within a short period can lead to measuring uncertainties higher than those specified. Changes on the metrological properties of radiation thermometers will occur mainly if the permissible limits for the ambient conditions at the place of use are exceeded. This can lead to temporary or permanent disturbances or damage the radiation thermometer. Sometimes, the disturbances are also of a "creeping" nature and cannot be immediately detected during the measurement.

For radiation thermometers regular checks and recalibrations are therefore imperative. The measures described in the following are strongly recommended. Considering the state of the art and the costs, they should contribute to errors being detected at an early stage and rectified.