Pottery Studio Health & Safety: Silica Dust, COSHH & Risk Assessments

Part of Open Your Studio, our guide series for opening a pottery studio in the UK.

Most people opening a pottery studio aren't losing sleep over the wheels. They're worried about the paperwork: the risk assessment they've never written, the acronym everyone mentions but nobody explains, and the nagging thought that a member gets hurt and it turns out they missed something obvious. That's a fair thing to worry about, because other people's health is now your responsibility. The reassuring part is that safety in a clay studio comes down to a handful of habits, set up properly before you open, written down, and actually kept to.

One honest caveat before we start: we design and kit out pottery rooms, we're not health and safety consultants. This guide explains what we see working in studios and points you to the HSE guidance that sets the rules. For anything specific to your building or your staff, read that guidance or get a competent adviser to look at it. If you want a list to tick off as you go, the free Studio Setup Checklist covers everything below.

Silica dust is the hazard that matters most

Clay and many glaze materials contain crystalline silica. Wet, it's harmless. Once clay dries and gets disturbed, by sweeping, sanding or simply being walked into the floor, it becomes a fine dust, and the smallest particles (respirable crystalline silica, or RCS) hang in the air and get breathed deep into the lungs. Over years, that can cause silicosis and other serious lung disease. It doesn't hurt on the day, which is exactly why studios get careless with it.

The HSE sets a workplace exposure limit for RCS of 0.1 mg/m³, averaged over an eight-hour day. You can't see that amount of dust, so you don't manage it by eye. You manage it by not making dust in the first place. HSE's COSHH essentials series includes sheets written specifically for ceramics, including one on preparing glazes and colours, and they're worth printing for your folder.

Wet cleaning only, every session

This is the single habit that does most of the work, and it's the one to build into your timetable rather than leave to goodwill.

• No brooms, ever. Sweeping a clay floor is the fastest way to put silica in the air. Mop instead, and plan a floor that makes mopping easy.
• No dry sanding or scraping of greenware or bisque inside the making room. Smooth work while it's leather-hard, or use a damp sponge.
• Wipe benches, wheels and splash pans with a damp sponge at the end of every session, not once a week.
• Use a proper dust-class vacuum (M- or H-class, with a HEPA-grade filter) for anything dry. A domestic vacuum blows the finest particles straight back out of the exhaust.
• Reclaim trimmings wet. Dry scraps on the floor become dust underfoot. A bucket by every wheel solves it.
• Aprons and towels get washed, not shaken out. Fabric that holds dust carries it home.

Put the cleaning routine on the wall by the sink, and give the last fifteen minutes of every class to it. Members follow what they see the tutor doing.

Glaze materials, safety data sheets and COSHH

COSHH stands for the Control of Substances Hazardous to Health Regulations. In plain terms: list the hazardous things you use, work out who could be harmed and how, and put controls in place. For a pottery studio that means clay, glaze powders and oxides, kiln wash, and cleaning products.

Start by collecting a safety data sheet for every material you buy. Whoever sold it to you should provide one; ask if they haven't. The data sheet tells you the hazards and the precautions, and your COSHH assessment turns that into rules for your room. A few that come up in almost every studio:

• Mix glazes from powder in a separate area, away from the wheels, adding powder to water rather than the other way round, with a suitable respirator (HSE's ceramics sheet explains which).
• Store powdered materials in sealed, clearly labelled containers. Some colourants and fluxes are toxic, and students shouldn't be handling them unsupervised.
• Buy lead-free glazes, and if work is meant for food or drink, use glazes the manufacturer states are food-safe at your firing temperature.
• No eating or drinking at the bench. Give people somewhere else to put their tea.

HSE's short guide "Working with substances hazardous to health" is the best starting point if you've never done a COSHH assessment.

Writing your risk assessment

Every employer has to assess the risks in their workplace. If you employ five or more people, the law requires you to write down the significant findings. Write it down anyway, whatever your headcount. Your insurer, your landlord and any school or council you work with will ask to see it, and the act of writing it makes you notice things.

HSE's guidance on managing risks and risk assessment at work sets out the method: spot the hazards, decide who might be harmed and how, decide your controls, record it, and review it when something changes. For a pottery studio, the usual list looks like this:

The kiln room

A kiln is the one piece of equipment in the building that can genuinely burn someone or start a fire, so it gets its own space. Keep it in a separate, lockable room or caged area, with a non-combustible floor, at least 30 cm clearance to walls and room to walk all the way round. Kilns give off fumes as they fire, particularly in the early stages of a bisque, so you need extraction to outside and nobody sitting in that room during a firing. Our guide to kiln ventilation and safety covers extraction in detail, and electrical requirements covers the circuit.

Decide who is allowed to load, programme and unload the kiln, train them properly, and keep it to them. "Someone trained to load and programme the kiln" is on our list of things new studios forget, and it's the one that causes the most expensive mistakes.

Inducting members and students

Nobody should touch a wheel until they've had an induction, and you should keep a record that they've had one. It doesn't need to be long. Fifteen minutes on the house rules covers it: wet cleaning, where the sink and clay trap are, no food at the bench, the kiln room is staff only, how to report a broken tool or a spill, and what to do in a fire. Ask people to sign that they've had it. For open-access members working without a tutor, keep the rules on the wall by the door, because people forget.

Tutors need a fuller version, including the risk assessment itself, first aid arrangements, and what to do if a student feels unwell.

Children, schools and paint-your-own

Children are more vulnerable to dust and toxic materials, and less reliable about washing their hands. If you run children's classes, school sessions or a paint-your-own offer, tighten the rules rather than relaxing them. Use ready-made, brush-on glazes and underglazes labelled for use with children, never powdered materials. Keep firing entirely in adult hands. Make handwashing part of the session, not an afterthought. Think about supervision ratios, and if you're working with a school or council they'll usually have their own requirements, so ask. Staff working with children may need DBS checks; check what applies to your setup.

First aid, accidents and the folder

HSE's first aid at work guidance explains how to work out what you need: a stocked kit, someone responsible for it, and something for burns and eyes is the minimum we'd expect in any clay room. Keep an accident book. Some incidents, including certain injuries to members of the public, must be reported to HSE under RIDDOR, so read HSE's RIDDOR guidance before you open, not after something happens.

Then keep it all in one place, paper or digital: your risk assessment, COSHH assessments and safety data sheets, induction records, the accident book, the electrician's certificate for the kiln circuit, a kiln firing and maintenance log, and the date you last reviewed each one. A fire risk assessment belongs in there too. When an inspector, insurer or new tutor asks, you hand them the folder.

Setting up at home rather than opening to the public? Our home kiln buying guide is the better place to start.

Keep reading

• Kiln Ventilation & Safety — extraction, clearances and fumes, explained for studios.
• Insurance for a Pottery Studio — the covers you need and why kilns matter.
• Finding & Fitting Out a Space — floors, drainage and power to check before signing.