Quick answer
The silica risk from an engineered stone benchtop sits in the workshop where the slab is cut, not in your finished kitchen. WorkSafe puts engineered stone in excess of 90 per cent crystalline silica against less than 45 per cent for granite, and cutting, grinding and polishing it throws off respirable dust that causes accelerated silicosis. It is still legal in New Zealand — the control is the fabricator, not the product. Ask whether water is fed to every blade, pad and CNC head, whether there is on-tool extraction and serviced LEV, whether respirators are fit tested, and who does the health monitoring. Engage the fabricator directly and you carry duties under the Health and Safety at Work Act 2015 too.
Key points
- WorkSafe puts engineered stone in excess of 90 per cent crystalline silica, against less than 45 per cent for granite and around 2 per cent for marble and limestone.
- Engineered stone is not banned in New Zealand — Australia banned it from 1 July 2024, MBIE's consultation closed on 18 March 2025, and no decision has been confirmed since.
- WorkSafe cut the exposure standard for respirable crystalline silica to 0.025 mg/m³ in November 2023, and says significant risk to workers remains even at that level.
- The industry's RCS Accreditation Programme is voluntary: as at March 2024 only 10 fabricators were fully accredited out of the 83 who had been through it.
- Engage a fabricator directly and you are a PCBU under the Health and Safety at Work Act 2015 — section 34 makes you consult, co-operate and co-ordinate.
Over 90 per cent silica. Granite is not close.
Stone tops for eighteen townhouses in Onehunga. The developer wants the three-bedders in engineered stone, the rest in laminate, and he has already picked the colour. What he has not asked — what almost nobody asks — is where the stone gets cut, and by whom, and with the water on or off. That question matters more than the colour.
This is not an article telling you engineered stone is evil, or that it is about to be outlawed here. It is not banned, and the slab in a finished kitchen is not hurting anybody. The hazard is a workshop hazard and it lands on whoever holds the grinder. What follows is what to ask, and what a straight answer sounds like. A starting point, not legal advice.
The dust is made in the workshop, not in your kitchen
Respirable crystalline silica is the fraction of stone dust fine enough to travel deep into the lung and stay there. You cannot see it. It gets made when a slab is cut, ground, drilled, edged or polished — which is why the exposure belongs to the fabricator and the installer, not to whoever wipes the bench down at night.
Concentration is what makes engineered stone different. WorkSafe puts its crystalline silica content in excess of 90 per cent, against less than 45 per cent for granite and around 2 per cent for marble and limestone. Same cut, same tool, far more silica in the air. That is why the disease attached to it is accelerated silicosis — a more aggressive form that appears sooner and moves faster than chronic silicosis. Our comparison of engineered stone, laminate and solid surface covers how they behave once in.
Where New Zealand actually sits
Australia banned the manufacture, supply, processing and installation of engineered stone from 1 July 2024. New Zealand did not follow. MBIE consulted on five options, from leaving the settings alone through to licensing the workplaces that cut and polish it and limiting supply — including a partial ban aimed at stone with 40 per cent or more crystalline silica. Submissions closed on 18 March 2025, and no decision has been confirmed since.
The number that has moved is the exposure standard. WorkSafe cut it for respirable crystalline silica from 0.05 to 0.025 mg/m³ in November 2023, having already brought it down from 0.1 in November 2019. MBIE's own material calls a WES advisory rather than a mandatory level that must not be exceeded, unless prescribed in regulations — a technicality, not a defence, since the duty to minimise risk so far as is reasonably practicable applies regardless. WorkSafe says significant risk remains at 0.025 mg/m³. Meeting the standard is not the same as being safe.
What a good workshop actually does
Water is the whole game. WorkSafe's guidance is to keep the material wet while it is worked — water fed to the blade, on-tool suppression — and to isolate dusty work behind barriers or inside CNC machines. The don'ts are just as specific: no dry sweeping, no compressed air to blow dust off benches, floors or overalls. Freshly exposed silica is also more toxic than weathered silica, and water speeds the weathering as well as knocking the dust down.
Respirators come last, and that ordering is not a preference. WorkSafe is explicit that PPE is the least effective control and should not be the first or only one considered. A respirator that seals against the face is worth little if it has never been fit tested to that worker's face — ask about AS/NZS 1716 for the respirator and AS/NZS 1715 for how it is selected. A shop that leads with "the boys all wear masks" has no engineering controls.
A respirator is the last line, not the plan.
| Ask this | A good answer | Worry if you hear |
|---|---|---|
| How do you cut and polish? | Water fed to every blade, pad and CNC head; slurry cleaned up wet. | "We only dry cut the small stuff." |
| What extraction is on the tools? | On-tool extraction and LEV, serviced on a schedule, with records. | A shop vac and an open roller door. |
| Are respirators fit tested? | Per worker, to AS/NZS 1715 and 1716, recorded and repeated. | "There's a box of P2s by the door." |
| Do you do exposure monitoring? | Yes, read against the 0.025 mg/m³ standard. | "We've never needed to." |
| Any health monitoring? | Yes, via an occupational health provider, with consent. | "Our guys are young, they're fine." |
| Are you on the RCS register? | Yes — this level, last audited this date, here's the certificate. | "That's just an Australian thing." |
| Where does site cutting happen? | Rarely, wet, area controlled, other trades clear. | On the driveway with a grinder. |
Accreditation tells you something. It doesn't tell you everything.
There is a voluntary scheme, and it is the easiest thing here to check yourself. The New Zealand Engineered Stone Advisory Group and IMPAC run the Respirable Crystalline Silica Accreditation Programme, which audits fabricators against a good practice guide and lists those that pass — Level 2 provisional, Level 3 fully accredited — on a searchable register.
MBIE's material records that as at March 2024, 83 fabricators had been through the programme: 10 fully accredited, 49 provisional, 15 who did not meet the standard. Set that against a sector the same material puts at roughly 130 to 160 businesses, and a large slice has never been audited. MBIE also records IMPAC and NZESAG's own advice that engagement with the more problematic third of fabricators remains difficult and their participation is low. The shops that most need auditing are the least likely to be on the register you are checking.
WorkSafe's enforcement record says the same from the other end. Across its assessments from June 2023 to October 2024, inspectors visited 102 engineered stone businesses and took 131 enforcement actions across 67 of them. Two in every three visited were doing something an inspector would not walk away from — five years into a targeted campaign.
If you engage the fabricator, you carry duties too
Section 34 of the Health and Safety at Work Act 2015 is the one to know. Where more than one PCBU has a duty in relation to the same matter, each must, so far as is reasonably practicable, consult, co-operate with and co-ordinate activities with the others. Duties overlap constantly in a contracting chain, and WorkSafe's position is that a PCBU cannot transfer its duties or contract out of them. You can agree who does what. You cannot agree that it stops being yours.
In practice it is a question of scale. A homeowner engaging one kitchen company that carries the whole job has a short chain and one party to ask. A developer running twenty units with a separate stone supplier, installer and builder has several PCBUs holding overlapping duties and nobody obvious to ask. That is much of why builders outsource kitchens to a single supplier — fewer interfaces, fewer duty holders, fewer seams to lose something down. It does not delete your duty. It makes discharging it realistic.
You can tell in ten seconds. If the floor's dry and the air smells like a quarry, you've seen enough — the shops that do it properly are wet, and they're wet everywhere.
Laminate is our own back yard, and it deserves a word. We run a workshop in East Tamaki cutting melteca and board all day, and swapping stone for laminate hands nobody a clean conscience — it trades respirable silica for wood dust, which WorkSafe links to occupational asthma and lung cancer. The dust duty follows the cutting, whatever is being cut. If you are choosing on wear and price rather than dust, the cost and value comparison between laminate and stone is the more useful read.
What goes wrong
Most failures are not a workshop deciding to poison its staff. They are gaps — between materials, between sites, between the audit in March and a wet Tuesday in September.
- You audited the wrong company. Many kitchen companies do not own a stone shop — they buy the tops in. If a third party cuts, that is who the questions are about.
- Mask theatre. P2s from a box by the door, no fit testing, beards under the seal, no records. It looks like a control and is not one.
- The knock-off broom. Controls run all day, then someone sweeps dry at four o'clock and puts the day's settled dust back in the air.
- Health monitoring that never starts. Deferred every year because nobody is coughing yet — and accelerated silicosis does not announce itself early.
- Silica-free marketing doing the work of a control. Low-silica surfaces do cut the load, but the dust duty stays.
The site cut catches otherwise good jobs. A top can be templated and fabricated wet in a controlled shop, then undone by one dry grinder cut on the driveway because the tap turned up late. That is why getting the measure right before anything is fabricated matters, and why sequencing the trades around the install is a health question and not only a programme one — a dry cut in a closed unit exposes the sparky and the painter too. Take the cheapest of five stone quotes without asking any of this and you have chosen against dust control. Worth knowing what sits inside a benchtop line first.
What to get in writing before you sign
- The fabricator's trading name — and whether it is the company on your contract.
- Their RCS register level and the date last audited, not just a claim that they are on it.
- Dated evidence of LEV servicing and of fit testing per worker, not a receipt for masks.
- A written no-dry-cutting position for your site, and what happens when a late change needs a hole.
Frequently asked questions
Is engineered stone banned in New Zealand?
No. Australia banned engineered stone from 1 July 2024; New Zealand did not follow. MBIE consulted on options from the status quo through to licensing fabrication workplaces and limiting supply, submissions closed on 18 March 2025, and no decision has been confirmed since. It stays legal to import, fabricate, supply and install here — the risk is a dust-control problem, not a legality one, though that could change.
Is the engineered stone benchtop already in my kitchen dangerous?
An intact, installed benchtop is not generating respirable dust, so it is not exposing your household. The hazard comes from cutting, grinding, drilling and polishing, which is why it falls on fabricators and installers rather than owners. It becomes your problem only if somebody cuts into it later — a retrofitted tap or sink — and does it dry, indoors, with no extraction.
Could I be liable if my fabricator gives a worker silicosis?
Engage the fabricator and you are a PCBU under the Health and Safety at Work Act 2015. Section 34 requires PCBUs sharing a duty to consult, co-operate and co-ordinate so far as is reasonably practicable, and WorkSafe's position is that you cannot transfer duties or contract out of them. Whether that becomes liability in a particular case is a question for a lawyer. Practically, asking these questions and keeping the answers is part of discharging the duty.
How do I check whether a fabricator is accredited?
The RCS Accreditation Programme, run by IMPAC with the New Zealand Engineered Stone Advisory Group, publishes a register listing only fabricators audited to Level 2 provisional or Level 3 fully accredited. Search it before you sign, and ask which level they hold and when they were last audited. Be realistic about what it proves: the programme is voluntary, and as at March 2024 only 10 fabricators were fully accredited out of the 83 who had been through it.
Should I just specify laminate and avoid the problem?
It takes respirable crystalline silica out of the equation, and for rentals, tight-budget builds and back-of-house, laminate is often the right call for reasons unrelated to dust. It does not take away the dust duty. Cutting laminate on particleboard produces wood dust, which WorkSafe links to occupational asthma and lung cancer and expects to be controlled at the source. Hold whoever cuts it to the same standard.
Ask the questions, then get a number
This matters commercially, not only morally: the answers correlate. A workshop with water fed to every head, extraction that gets serviced, respirators fit tested to named workers and health monitoring running is a shop that measures things and keeps records. That is the same shop that templates your tops on time. Dust control is a proxy for competence, and a better one than a showroom.
MTN Kitchens has run its own workshop in East Tamaki for 23 years — more than 2,000 kitchens, ten-plus a week, Site Safe qualified because head contractors like Spencer Henshaw put kitchen work through us. We supply and install under one contract and one invoice, so one party is accountable for the lot. Send the unit count and a rough scope, or drawings, and a trade-priced number comes back inside 24 hours. Ask us where the stone gets cut — you should be asking everybody you ring.