Test Instrument Calibration Register

Purpose. This register lists every test instrument, refrigerant recovery unit, scale and leak detector the business uses for mandatory tests, with its calibration status and the rules for its use.

1.Why calibration matters

A test result is only as good as the instrument that produced it. A certificate signed on the basis of an uncalibrated instrument is not defensible. This register ensures that every instrument used for a mandatory test has a current calibration certificate traceable to national standards and that instruments out of calibration are withdrawn.

2.Instruments covered

Multifunction installation testers, insulation resistance testers, residual current device testers, earth loop testers, clamp meters used for commissioning records, portable appliance testers, refrigerant scales, recovery units, electronic leak detectors, vacuum gauges and thermal imaging cameras.

3.Calibration intervals

Installation testers, appliance testers and insulation testers are calibrated every twelve months. Refrigerant scales and vacuum gauges are calibrated every twelve months. Leak detectors are checked against a reference leak every six months. Thermal imaging cameras are calibrated every twenty-four months. Any instrument that has been dropped or gives doubtful readings is withdrawn and checked regardless of its due date.

• Installation and appliance testers: 12 months
• Insulation resistance testers: 12 months
• Refrigerant scales and vacuum gauges: 12 months
• Leak detectors: 6 month reference check
• Thermal imaging cameras: 24 months

4.Using the register

Before every job, the technician checks the instrument register for the instrument they intend to use and records its identification on the test sheet. Instruments due within thirty days are flagged and the Service Coordinator arranges calibration. Instruments past due are tagged out of service and removed from the van.

5.Records

Calibration certificates are filed against the instrument entry. The register is reviewed monthly by the Safety, Quality and Business Support Manager and reported at the quarterly internal audit.