Meeting test method requirements for equipment out of calibration

Industry News December 1, 2021
NATA team

At times, a calibration report for an item of equipment at a facility shows that the equipment does not comply with the requirements of the test method.   

Unfortunately, this is usually not discovered until assessment by NATA after test reports have been issued for tests using that equipment. 

The facility needs to determine if the equipment is fit for use by recalibration or replacement. 

When this happens, they should: 

  1. Immediately cease issuing test reports when the equipment is to be used (this needs to be part of the response for the condition raised) 
  1. The equipment should be recalibrated or replaced before proceeding with testing 
  1. A sensitivity analysis of the effect of the amount the equipment is out of specification needs to be undertaken to determine the effect on the results 
  • If the effect is minimal, all test reports issued since the calibration report for tests using the equipment will need to be re-issued as amended reports with details of the out of specification equipment and how it may have affected results. 
  • If the effect is significant -i.e., will change the results, reports since the calibration report date are to be withdrawn.

In another case, it has been found that the range of calibration does not cover the range of the tests being performed – for example – CBR load cell calibration from 5 to 50kN instead of 0.5 kN. 

  • If the load cell has been previously calibrated in the lower range and a subsequent recalibration shows it complies with requirements, it is considered that results for the reports issued where the range was incomplete are most likely to be satisfactory. 
  • If the load cell had not been calibrated previously in the lower range and a subsequent recalibration shows it complies with requirements, test reports are to be amended and re-issued stating the non-conformance of the calibration of the equipment. 
  • If the lower range does not meet specification, all reports which were covered by the lower range are to be withdrawn. 

Please contact NATA if you have any questions regarding any of these points.