Is there a legal interval?
No single interval is written into New Zealand law — and that is more demanding than it sounds, not less.
Your legal duties sit in the Health and Safety at Work Act 2015 and the Electricity (Safety) Regulations 2010. Both require that electrical equipment is safe and maintained in a safe condition. Neither prescribes an interval, which means the interval you choose is yours to justify.
WorkSafe's position: testing and tagging "is one useful way to check electrical equipment is safe. However, it's not mandatory. What is legally required is that equipment is electrically safe and maintained in a safe condition."
So the obligation does not go away — it moves. Instead of following a number someone handed you, you need an interval you can explain, and a record showing you applied it. AS/NZS 3760 is a standard, not a law, and working to it is the most widely accepted way of demonstrating you have met the duty. That is why almost everyone uses it, and it is why the reasoning matters as much as the number. More on the underlying duty in what the law actually requires of you.
Recommended intervals by environment
These are the intervals AS/NZS 3760 works from for equipment in a typical New Zealand workplace.
| Environment | Typical interval | Why |
|---|---|---|
| Construction and demolition sites | 3 months | Outdoors, damp, physical abuse, frequent relocation |
| Hire and lease equipment | 3 months, or before each hire | Unknown users, unknown treatment between hires |
| Factories, workshops, warehouses | 6 months | Flexing leads, dust, vibration, mobile plant |
| Commercial kitchens and laundries | 6 months | Heat, steam, grease, constant handling |
| Offices, retail, schools, hospital wards | 12 months | Controlled environment, light handling |
| Low-risk stationary equipment | Up to 5 years | Rarely moved, benign environment — risk assessment required |
A tolerance of roughly two weeks either side is generally accepted, and can be varied where a risk assessment supports it.
Careful with the tables. AS/NZS 3760 is a copyrighted document sold by Standards New Zealand. This page summarises and explains it — it does not reproduce it. If you are setting a compliance programme, buy the current edition.
The five-year low-risk allowance
The 2022 edition permits intervals of up to five years for equipment in a low-risk category — a desktop PC, a monitor, a printer in an office, or equipment in a server room that never moves.
It is not automatic. To rely on it you need:
- A documented risk assessment covering the equipment and its environment
- Evidence the equipment is not subject to flexing, moisture, heat or physical abuse
- A register recording the decision and the reasoning, not just the date
- Routine visual checks in between — cords, plugs and casings, by the user
In practice most sites end up with a mixed schedule: five years on fixed office IT, twelve months on anything with a person on the end of it, six months in the workshop. That is precisely what an asset register exists to keep straight.
Intervals by equipment type
Environment is the first filter, but equipment type shifts things within it.
- Hand-held tools — drills, grinders, heat guns, sanders. The cord is flexed constantly and the tool gets dropped. Test at the shortest interval that applies to the environment; never extend these.
- Extension leads, power boards and portable RCDs — statistically the most common point of failure on any site. Treat them at least as often as the tools they feed. Portable RCDs also need push-button testing far more frequently, often daily on construction sites.
- Portable equipment moved regularly — vacuum cleaners, heaters, kettles, portable lighting. Standard environment interval.
- Stationary equipment rarely moved — can often justify a longer interval than its surroundings would suggest, if the environment itself is not the risk.
- Desktop IT — the classic candidate for the five-year allowance, provided it genuinely never moves.
How to set your own interval defensibly
The mistake most businesses make is applying one interval to an entire site. A twelve-month blanket is simultaneously too frequent for the office PCs and not frequent enough for the workshop grinder.
A defensible approach:
- Split the site into zones by environment — office, workshop, yard, kitchen.
- Set a base interval per zone using the table above.
- Adjust per equipment type within the zone, shortening for hand-held and lead items.
- Write down why. One paragraph per zone. This is the risk assessment, and it is what turns a number into a defensible position.
- Review annually, or whenever the work changes.
Not sure where your equipment lands? Our testing frequency checker walks through it in four questions and gives you the reasoning to put in your register.
What you need to record
A tag on the cord is not a record. If you are asked to demonstrate compliance — by WorkSafe, an insurer, or a client's prequalification system — you want, per item:
- An item identifier and its location
- The test date and the result
- The tester's name
- The next due date
- The justification for the interval
Most businesses do not have this. It is the single most common gap we find, and it is the reason a register matters more than the tagging itself.