Calibration date vs storage time

Applies to

T&M products delivered with a Calibration Certificate


What is the impact of storage period on the recommended calibration interval?


Up to a reasonable maximum storage period (see below), EXFO guarantees that the proper storage at room temperature (23 °C ± 5 °C) will not affect the performance of the Test & Measurement Instruments and will not reduce the recommended validity period before requiring a new calibration.

Here is a guide that may help you determine your next calibration.

Next calibration date = Date of first usage* + recommended calibration period (as specified in the user guide)

*Date of first usage can be used if proper storage conditions stated above where met. When date of first usage is not known, reception date can be used.

Condition related to Maximum Storage Period:
The next calibration date should be before the calibration date on certificate + recommended calibration period + maximum storage period (as specified in the user guide)


The 2 examples below will help you to interpret EXFO's recommendation.

Example 1 ( not exceeding the maximum storage period)

Recommended Calibration Interval ( from user manual): 12 months

Date of calibration ( on Certificate):  Sept 1, 2022

Date of first use: Feb 1, 2023

Maximum Storage period (from user manual): 6 months

Next recommended calibration: before Feb 1, 2024


Example 2 (exceeding the maximum storage period)

If the same instrument as above was first used May 1, 2023

Next recommended calibration: before March 1, 2024


NOTE: Although the recommended Calibration intervals are explained in the product user manuals, for convenience you can also consult this knowledge article that provides the same information for the majority of EXFO products.