COSHH by Area

COSHH in the Kitchen

The Hazardous Substances in a Commercial Kitchen and How to Control Them

The kitchen is where most of a hospitality business uses its most hazardous substances. Oven and grill cleaners, heavy-duty degreasers, sanitisers, dishwasher and rinse-aid chemicals, descalers, and drain unblockers are all in daily use, often handled neat by kitchen porters during clean-down. Add the flour dust and cooking fumes that the work itself creates and the kitchen is the single most important area to get right in your COSHH assessment. This guide works through the substances a commercial kitchen actually uses, the people most exposed to them, and the controls that an environmental health officer expects to see when cleaning chemicals are stored and used so close to food.

Read a kitchen chemical safety data sheet See COSHH features

Key takeaways

The kitchen uses the most hazardous substances on site, from corrosive oven cleaners and drain unblockers to sanitisers and descalers.

Kitchen porters are the most exposed because they handle neat chemicals during clean-down, often when tired.

Substitute where you can: pre-diluted sanitiser and less corrosive cleaners remove risk at the source.

Never mix products, especially bleach with acid descalers, and keep chemicals well away from food.

Store the assessment and safety data sheets where the cleaning happens, not only in the office.

The Chemicals on a Kitchen Shelf

A typical commercial kitchen holds a recognisable set of products. Oven and grill cleaners are strongly alkaline and corrosive, designed to shift carbonised grease, and they are the most aggressive thing most chefs handle. Heavy-duty degreasers cut grease on canopies, hobs, and floors and are usually irritant or corrosive in concentrate. Sanitisers and combined detergent-sanitisers are used constantly on food contact surfaces. Dishwasher detergent and rinse aid, often plumbed in from bulk containers, are corrosive and high pH. Descalers for the dishwasher, combi oven, and coffee machine are acidic. Drain unblockers are among the most dangerous products on site, frequently containing sodium hydroxide or sulphuric acid. Each of these arrives with a safety data sheet, and every one of them needs to appear in the kitchen COSHH assessment with its dilution, its protective equipment, and its emergency response set out clearly.

Who Is Most Exposed and How

Kitchen porters carry the highest exposure because they handle neat chemicals at the sink and during the deep clean, often at the end of a long shift when concentration drops. The main routes are skin contact from splashes and prolonged wet work, breathing in mist and fumes when spraying degreaser or cleaning a hot canopy, and eye damage from corrosive splashes. Chefs are exposed to flour dust when baking and to oven cleaner residue if surfaces are not rinsed before cooking resumes. Young workers and new starters, common in kitchen porter roles, are more vulnerable and need clear instruction before they touch anything corrosive. The kitchen COSHH assessment should name these roles and match the controls to the people who actually do the work, not to an idealised member of staff who reads every label.

Controls That Work in a Busy Kitchen

Start with substitution: buy pre-diluted sanitiser instead of concentrate, choose a less corrosive oven cleaner where it still does the job, and never let anyone mix bleach with an acid descaler or a different cleaner. Use dosing systems and clearly marked dilution bottles so staff are not guessing. Make sure the extraction canopy is working when cleaning chemicals are being sprayed, and clean the oven when it has cooled rather than fighting fumes off hot metal. Provide and require chemical-resistant gloves, an apron, and eye protection for the corrosive products, and keep an eyewash to hand. Store chemicals away from food, ideally in a dedicated cupboard, never decanted into drinks bottles. Brief every kitchen porter on the products they use and keep the assessment and safety data sheets where the sink and the cleaning store are, not only in the office.

What to do next

List every chemical under the sink and in the cleaning store

Capture oven cleaner, degreaser, sanitiser, dishwasher chemicals, descalers, and drain unblocker, and collect the safety data sheet for each.

Fit dosing or clearly labelled dilution bottles

Remove guesswork from dilution so kitchen porters use the right strength every time and never decant into unlabelled containers.

Brief kitchen porters before they handle corrosive products

Make sure new starters know the controls for oven cleaner and drain unblocker before they ever use them, and record the briefing.

Common mistakes to avoid

Mistake

Storing cleaning chemicals next to or above food

Instead

Keep chemicals in a dedicated cupboard away from food, ingredients, and packaging. Inspectors look hard at chemical storage in kitchens because contamination risk is high.

Mistake

Cleaning a hot oven or canopy without extraction running

Instead

Spraying degreaser or oven cleaner onto hot metal drives off fumes. Let surfaces cool and keep the extraction on while cleaning.

Frequently asked questions

What COSHH substances are used in a commercial kitchen?

The main ones are oven and grill cleaners, heavy-duty degreasers, sanitisers, dishwasher detergent and rinse aid, descalers for the dishwasher and coffee machine, and drain unblockers. Flour dust and cooking fumes are also covered by COSHH.

Where should cleaning chemicals be stored in a kitchen?

In a dedicated, well-ventilated cupboard away from food, ingredients, and food packaging. They should be kept in their original labelled containers, never decanted into drinks bottles, and corrosive products kept separate from acids.

Do kitchen porters need COSHH training?

Yes. Kitchen porters handle the most hazardous products neat, so they must be briefed on the chemicals they use, the dilutions, the protective equipment, and what to do after a splash or spill. Keep a record of that training.

Is flour dust a COSHH hazard?

Yes. Flour dust can cause occupational asthma and dermatitis with repeated exposure, so bakeries and kitchens that handle flour in quantity should cover it in their COSHH assessment and control dust where they can.

Hazardous Substances in Hospitality