One-paragraph definitions
Test and tag is the in-service safety inspection and testing of portable electrical equipment to AS/NZS 3760. It checks that the equipment is electrically safe to use — that the insulation is intact, the earth conductor is continuous, the polarity is right and the casing is undamaged.
Calibration is the documented comparison of a measuring instrument against a reference standard traceable to national standards. It produces a certificate that records what the instrument read before and after adjustment.
A side-by-side comparison
A simple comparison:
- Test and tag — confirms the equipment is safe to plug in. Standard: AS/NZS 3760. Output: a tag and a register entry.
- Calibration — confirms the instrument reads accurately. Standard: ISO 9001 quality system + manufacturer specs. Output: a calibration certificate.
- Test and tag is a workplace safety control. Calibration is a measurement integrity control.
- A power drill is test-and-tagged. A multimeter is BOTH test-and-tagged (it is a portable electrical item) AND calibrated (its readings have to be accurate).
Examples by tool
It is easier to see when each one applies by thinking about specific tools:
- Multimeter — both. Test & tag for electrical safety; calibration for accuracy.
- Power drill — test & tag only. There is no measurement to calibrate.
- Vernier caliper — calibration only. It is mechanical, so AS/NZS 3760 does not apply, but its readings need to be calibrated.
- Thermocouple — calibration only. There is no power lead to test and tag.
- Bench multimeter — both. It runs from mains power, so it needs test and tag, and it takes a measurement, so it needs calibration.
How to schedule both without doubling the admin
The two services run on different footings: test & tag happens at your premises, calibration happens in our Caversham lab. The practical way to combine them is to align the schedules — our technician runs the AS/NZS 3760 round on site and collects any instruments that are due for calibration on the same trip, then returns them with their certificates. You get one supplier, one register and one invoice covering both.
This works particularly well on construction sites (3-monthly test & tag alongside annual calibration of the multimeters and clamp meters the site uses) and in manufacturing (annual cycles on both).
Compliance frameworks each maps to
Test and tag maps to WHS workplace safety obligations and AS/NZS 3760. Calibration maps to ISO 9001 quality management and any sector-specific quality requirements (mining prequalification, customer PPAP, etc.). Different parts of the same business often own them — HSEQ for test & tag, quality or production for calibration — which is why they can drift apart unless explicitly scheduled together.