Calibration can be affected by the use and care of the torque wrench. Torque wrenches are precision instruments and should be stored in a safe place, such as in their original case in a location that is not subject to extreme temperatures or high humidity.
Clicker wrenches should always be turned down to the lowest setting, but no further, to relax the spring and reduce spring wear.
When using the torque wrench, do not drop it or overload it with a handle or pipe extension. Using this type of extension can exceed the rated torque of the wrench, causing possible wrench failure.