What are the factors that must be done before doing the transmitter calibration

What should be done before the calibration of a transmitter

The transmitter should be isolated from the process

1.clarify job-related risk and hazards and how to mitigate them according to the work steps,

2.Gather all information eg ILD and DATA sheet,

3.The test equipment must be checked like if it is proper or not

4.use acceptable calibration equipment which means the accuracy of the calibrating equipment must be greater than that of the pressure measurement system,

5.Obtain a work permit with clear job steps