If you use, store, or create hazardous substances at work, you need COSHH assessments. This applies to most UK workplaces — from offices using cleaning products to factories handling industrial chemicals. Understanding whether you need COSHH assessments is the first step to legal compliance and protecting your workforce.
Which best describes your situation?
Let's identify your COSHH requirements.
Who needs COSHH assessments?
The short answer: any employer (or self-employed person) who uses, stores, or creates hazardous substances.
Employers
Under the Control of Substances Hazardous to Health Regulations 2002, all employers must:
- Identify hazardous substances used or created in their workplace
- Assess the health risks they present
- Decide what control measures are needed
- Put those controls in place
- Keep them working properly
- Provide information and training to employees
If you employ even one person and use any hazardous substance — including common cleaning products — you need COSHH assessments. There's no minimum company size threshold.
The "5 employee" rule
You must record your COSHH assessment if you employ 5 or more people. However, you still need to conduct the assessment even if you employ fewer than 5 people — you just don't have to write it down.
That said, recording assessments is best practice regardless of company size because:
- It demonstrates due diligence if inspected by HSE
- It helps you remember what you decided
- It makes training new employees easier
- It provides evidence if someone becomes ill
- It helps you review and update controls
Self-employed considerations
If you're self-employed, you have the same COSHH duties as employers for:
Protecting yourself:
- Assess risks to your own health
- Put control measures in place
- Use PPE appropriately
- Monitor your health if necessary
Protecting others:
- Anyone else who might be affected by your work
- Members of the public
- Other contractors on site
- Customers in whose premises you work
Self-Employed COSHH Scenarios
Sole Trader Working Alone
- •Mobile car valeter using cleaning chemicals
- •Self-employed painter using paints and solvents
- •Window cleaner using cleaning solutions
- •Still need to assess risks to yourself
- •Must protect public and property owners
- •Should record assessments as evidence
Self-Employed with Employees or Contractors
- •Small builder with labourers
- •Cleaner employing assistants
- •Decorator with apprentice
- •Must assess risks to all workers
- •Must provide training and PPE
- •Must record assessments (5+ people)
Bottom line: Whether you work alone or with others, if you use hazardous substances, you need COSHH assessments. The main difference is the recording requirement.
Landlords and property managers
If you're a landlord or manage properties, you need COSHH assessments if you:
- Employ cleaners or maintenance staff
- Provide cleaning materials for use by staff
- Store hazardous substances on the premises
- Arrange for contractors to use hazardous substances
If you hire contractors who bring their own materials, they're responsible for COSHH assessments for their work. However, you should check they have proper assessments in place, especially if they're working in occupied premises.
Common substances requiring assessment
Many employers are surprised to learn how many "ordinary" workplace products are hazardous substances requiring COSHH assessment.
Cleaning and maintenance
Almost every workplace uses these:
- Bleach — Corrosive, irritant, dangerous fumes if mixed with other chemicals
- Toilet and bathroom cleaners — Often acidic or alkaline, corrosive
- Oven and grill cleaners — Highly alkaline, severe skin and eye hazard
- Degreasers — May contain solvents, flammable, harmful by inhalation
- Disinfectants — Can cause skin sensitisation and respiratory irritation
- Floor cleaners and polishes — May be slippery hazard, some contain solvents
- Glass cleaners — Usually alcohol-based, flammable
- Descaling products — Acidic, corrosive
Just because you can buy it in a supermarket doesn't mean it's not hazardous. Common household products become hazardous substances when used at work and must be assessed under COSHH.
Office and education
Even predominantly "low-risk" environments have hazardous substances:
- Printer and copier toner — Fine dust, inhalation hazard
- Correction fluids and thinners — Solvent-based, harmful vapours
- Permanent markers — Solvent vapours, fire hazard
- Adhesives and glues — Some contain hazardous solvents
- Spray adhesives — Aerosol, inhalation hazard, flammable
- Art supplies — Paints, dyes, fixatives, solvents
- Science lab chemicals — Acids, alkalis, reagents, biological materials
- Pest control products — Biocides, toxic
Construction and trades
If you work in construction or trades, you're exposed to many hazardous substances:
- Cement and concrete dust — Corrosive, can cause dermatitis
- Silica dust — From cutting brick, stone, concrete — causes silicosis (lung disease)
- Wood dust — Especially hardwood — can cause asthma and nasal cancer
- Paints and varnishes — Solvent vapours, skin sensitisers
- Adhesives and sealants — May contain isocyanates (severe respiratory hazard)
- Expanding foam — Contains isocyanates
- Paint strippers — Highly hazardous solvents
- Welding and soldering fumes — Metal fumes cause respiratory disease
- Asbestos — Separate regulations, but extremely hazardous if disturbed
Construction work involving silica dust, wood dust, or welding fumes has led to many prosecutions and substantial fines. These are well-known respiratory hazards requiring specific controls, not just dust masks.
Manufacturing and industrial
Manufacturing environments typically have extensive hazardous substance use:
- Cutting fluids and coolants — Can contain biocides, cause dermatitis
- Oils and lubricants — Skin contact, fire hazard
- Solvents and degreasers — Vapour inhalation, flammable, some carcinogenic
- Metal working fluids — Mist inhalation hazard, biological contamination risk
- Electroplating chemicals — Acids, alkalis, toxic metal compounds
- Resin systems — Often contain isocyanates or other sensitisers
- Printing inks — Solvent vapours, skin contact
- Surface treatments — Acids, alkalis, chromates
Healthcare and laboratories
Healthcare settings have biological and chemical hazards:
- Disinfectants and sterilising agents — Toxic, corrosive, some carcinogenic
- Cytotoxic drugs — Extremely hazardous, cancer treatment medications
- Laboratory reagents — Acids, alkalis, solvents, biological cultures
- Anaesthetic gases — Exposure limits, extraction required
- Formaldehyde — Carcinogenic, used in pathology
- Latex — Allergen causing severe reactions in sensitised individuals
- Bodily fluids — Biological hazard (blood-borne viruses)
Hospitality and catering
Restaurants, hotels, and catering businesses use:
- Kitchen cleaners — Oven cleaners, degreasers (highly alkaline)
- Sanitisers and disinfectants — Quat-based products, bleach solutions
- Descalers — Acidic, for coffee machines and dishwashers
- Chlorine products — For water treatment, dishwashing
- Cooking oil — Hot oil burns hazard, but not typically a COSHH issue
Restaurant fined £40,000 after kitchen porter suffered chemical burns
A busy restaurant regularly cleaned its ovens using a highly alkaline oven cleaning product. Kitchen staff used it without proper training or protective equipment.
- ✗No COSHH assessment for oven cleaner
- ✗Staff not trained on hazards and safe use
- ✗No chemical-resistant gloves provided (staff used washing-up gloves)
- ✗Product used in poorly ventilated area
- ✗A kitchen porter suffered severe alkali burns to hands and forearms
- ✗Staff didn't know proper first aid (should rinse for 20 minutes minimum)
HSE prosecuted the restaurant. Fine of £40,000 plus £8,000 costs. The employee required hospital treatment and suffered permanent scarring. Civil claim for damages followed.
Common cleaning products can cause serious harm. Even products used for years need proper assessment, training, and controls. The cost of compliance is trivial compared to the harm caused and penalties imposed.
When you DON'T need a COSHH assessment
There are limited circumstances where COSHH assessments aren't required:
Domestic use
If you're using a product in the same way and quantity as domestic use, you may not need a full assessment. For example:
- Office kitchen using a normal bottle of washing-up liquid
- Receptionist using a can of air freshener
- Occasional use of supermarket-bought cleaning spray
However, even for domestic-type use, you should:
- Check the product has no hazard warnings
- Make sure it's used as intended
- Ensure adequate ventilation
- Not use large quantities
- Keep safety information available
The "domestic use" exception is narrow and often misunderstood. If you use products daily, in bulk, in industrial strength, or dilute concentrates, it's NOT domestic use — you need a COSHH assessment.
Minimal exposure
If exposure is minimal and clearly insignificant, you might not need a detailed assessment. But you must still:
- Identify the substance is hazardous
- Consider who might be exposed
- Decide the risk is minimal
- Record this decision
Minimal exposure might include:
- Occasional use of correction fluid by one person
- Rare use of a small amount of adhesive
- Incidental exposure to photocopier toner
This does NOT include:
- Daily use of any hazardous substance
- Use by multiple people
- Substances with Workplace Exposure Limits
- Substances causing cancer, asthma, or genetic damage
Substances not covered by COSHH
COSHH doesn't cover:
- Asbestos — Separate regulations (Control of Asbestos Regulations)
- Lead — Separate regulations (Control of Lead at Work Regulations)
- Radioactive substances — Separate regulations (Ionising Radiations Regulations)
- Hazards from temperature or pressure — Covered by other H&S law
- Medical treatment — Separate regulations for medicines administered to patients
Even though these aren't covered by COSHH, you still have duties under other health and safety legislation to assess and control these risks.
When in doubt, do the assessment. The time and cost are minimal compared to the risk of prosecution, employee illness, and potential litigation if you get it wrong.
Consequences of not having COSHH assessments
Failing to conduct COSHH assessments is a breach of health and safety law with serious consequences:
Legal penalties
- Improvement Notice — HSE orders you to comply within a set period
- Prohibition Notice — HSE stops the work until you comply
- Prosecution — Criminal offence, can result in:
- Unlimited fines in Crown Court
- Up to 2 years imprisonment for serious breaches
- Company directors personally prosecuted if involved
- Publicised on HSE enforcement notices database
Typical fines for COSHH failures
Recent prosecutions have resulted in:
- Small businesses: £10,000 - £50,000 plus costs
- Medium businesses: £50,000 - £200,000 plus costs
- Large businesses: £200,000 - £1,000,000+ plus costs
Fines are based on:
- Seriousness of the breach
- Likelihood of harm
- Your turnover/size
- Whether you knowingly breached the law
- Previous compliance history
Health consequences
Without proper COSHH assessments and controls:
- Acute effects: Chemical burns, poisoning, acute respiratory distress
- Chronic effects: Occupational asthma, dermatitis, cancer, lung diseases
- Long-term disability: Employees unable to work, permanent health damage
- Irreversible harm: Some exposures cause conditions that worsen even after exposure stops
Civil liability
If an employee suffers ill health due to hazardous substance exposure:
- Personal injury claims — Compensation for pain, suffering, loss of earnings
- Claims can be substantial — Especially for permanent disability
- Insurance may not cover — If you knowingly breached regulations
- Reputational damage — Loss of business, difficulty recruiting
Business impact
Beyond fines and claims:
- Work stoppage — If HSE issues a prohibition notice
- Loss of contracts — Many clients require COSHH compliance evidence
- Insurance issues — Premiums increase, coverage refused
- Recruitment problems — Reputation as unsafe employer
- Director disqualification — For serious or repeated breaches
The cost of proper COSHH compliance is minimal — basic assessments, training, and control measures. The cost of non-compliance can be catastrophic to individuals and businesses alike.
How many COSHH assessments do I need?
You need a separate assessment for each hazardous substance or task involving hazardous substances. However, you can be pragmatic:
Generic assessments
You can create generic assessments covering:
-
Multiple similar products used the same way
- Example: Several brands of general-purpose cleaner used for wiping surfaces
- Check they have similar hazards (read the safety data sheets)
- Ensure they're all used the same way
- List all products covered by the assessment
-
The same product used in different locations
- Example: Floor cleaner used in all buildings by the same cleaning team
- If the use, controls, and exposures are the same, one assessment covers all locations
-
Multiple employees doing the same task
- Example: All production operatives using the same cutting fluid
- One assessment covers all operatives in that role
Specific assessments
You need specific assessments when:
-
Different hazards exist
- Example: Solvent-based cleaner vs. water-based cleaner (different inhalation and fire risks)
-
Different uses or exposures
- Example: Spray application vs. brush application of paint (very different inhalation exposure)
-
Different control measures needed
- Example: Large-scale mixing requiring extraction vs. small amounts without
-
More hazardous substances
- Anything causing cancer, asthma, genetic damage, or reproductive harm
- Substances with Workplace Exposure Limits
- Biological agents
-
Vulnerable workers
- Young workers, pregnant workers, workers with known sensitivities
Assessment by task vs by substance
You can organise assessments either way:
By substance:
- "COSHH assessment: Acetone"
- Lists all tasks using acetone
- Good for tracking one substance through multiple uses
By task:
- "COSHH assessment: Parts cleaning process"
- Lists all substances used in that task
- Good for complex processes involving multiple substances
Choose the approach that makes most sense for your workplace. The important thing is that all hazardous substances and all exposures are covered.
Building Your COSHH Assessment Portfolio
Walk through your workplace and list every hazardous product, chemical, or process creating dusts/fumes
Get SDSs from suppliers for all hazardous substances. No SDS = can't assess = can't use safely
Identify where you can use generic assessments for similar products used the same way
Assess substances with WELs, carcinogens, respiratory sensitisers first
Record each assessment with substance details, risks, controls, and review date
Put control measures in place and train all affected employees
Generic vs specific COSHH assessments
Understanding when to use generic vs specific assessments saves time while ensuring compliance:
When generic assessments work
Characteristics of situations suitable for generic assessment:
- Low to medium hazard substances
- Standardised procedures
- Similar exposure across multiple uses
- Common control measures applicable throughout
- Multiple sites/teams doing identical work
Examples:
- Office cleaning using standard cleaning products
- Multiple retail outlets using the same cleaning schedule
- Chain restaurants with standardised cleaning procedures
- Schools using the same science lab chemicals across departments
When you need specific assessments
Characteristics requiring specific assessment:
- High hazard substances (carcinogens, asthmagens, toxic substances)
- Unique or complex processes
- Significantly different exposure levels
- Specialised control measures required
- Vulnerable workers involved
Examples:
- Welding in different environments (enclosed spaces vs open workshop)
- Laboratory work with varied chemicals and procedures
- Manufacturing processes with complex chemical reactions
- Healthcare procedures involving cytotoxic drugs
Generic vs Specific Assessments
Generic Assessment: Office Cleaning
- •Covers 5-10 common cleaning products
- •Used by cleaning team across 3 buildings
- •Standard procedures documented
- •Same PPE (gloves) for all products
- •Quick to create and easy to update
- •One assessment covers many situations
Specific Assessment: Welding Fumes
- •Different materials create different fumes
- •Enclosed space welding vs open area
- •Local exhaust ventilation specifications
- •Respiratory protective equipment fitting
- •Health surveillance requirements
- •Each situation needs detailed assessment
Bottom line: Use generic assessments for routine, low-hazard work with standardised procedures. Use specific assessments for high-hazard substances, complex processes, or significantly different exposures.
Industry-specific examples
Different industries have different COSHH requirements. Here's what you need to know:
Offices and professional services
Common hazardous substances:
- Cleaning products (cleaners, disinfectants, glass cleaners)
- Printer toner and copier supplies
- Correction fluids and solvents
- Adhesives for minor repairs
- Pest control products (if used in-house)
How many assessments?
- 1 generic assessment for routine cleaning (covering 5-10 products)
- 1 assessment for office equipment maintenance
- Specific assessments if you use specialist products
Main concerns:
- Skin contact with cleaning chemicals (dermatitis risk)
- Inhalation of toner dust
- Adequate ventilation in copier rooms
- Contractor management if cleaning is outsourced
Retail and hospitality
Common hazardous substances:
- Heavy-duty cleaning products (oven cleaners, degreasers)
- Disinfectants and sanitisers
- Descalers for coffee machines and dishwashers
- Floor cleaning and polishing products
- Pest control chemicals
How many assessments?
- 2-3 generic assessments (cleaning, sanitising, specialist products)
- Additional assessments for any unique substances
Main concerns:
- Staff turnover requiring regular training
- Multi-site operations needing standardised procedures
- Evening/night cleaning with less supervision
- Language barriers for some staff
Manufacturing
Common hazardous substances:
- Process chemicals and reagents
- Solvents and degreasers
- Adhesives and coatings
- Cutting fluids and coolants
- Dust and fumes from processes
- Waste materials
How many assessments?
- Multiple specific assessments (often 10-50+ depending on complexity)
- Each major process may need separate assessment
- Different substances, different exposures, different controls
Main concerns:
- Workplace Exposure Limits monitoring
- Local exhaust ventilation maintenance
- Health surveillance programmes
- Emergency procedures for spills/releases
Construction and trades
Common hazardous substances:
- Cement and concrete products (dermatitis risk)
- Silica dust (from cutting/drilling masonry)
- Wood dust (from sawing/sanding)
- Paints, varnishes, solvents
- Adhesives (especially those with isocyanates)
- Welding and cutting fumes
How many assessments?
- 5-15 assessments depending on trade scope
- Specific assessments for high-risk dusts and fumes
- Generic assessments for common paints/adhesives if similar use
Main concerns:
- Working at multiple sites (taking assessments and controls with you)
- Dust control (RPE, water suppression, extraction)
- Poorly ventilated spaces
- Demonstrating competence to clients/principal contractors
If you're a small subcontractor, many principal contractors require you to provide evidence of COSHH assessments before allowing you on site. Having assessments ready can help you win contracts.
Healthcare and social care
Common hazardous substances:
- Disinfectants and sterilising agents
- Cleaning chemicals
- Latex (allergen in gloves)
- Cytotoxic drugs (in oncology)
- Laboratory chemicals and reagents
- Biological hazards (blood, bodily fluids)
How many assessments?
- 10-20+ assessments depending on services provided
- Specific assessments for high-hazard substances (cytotoxics)
- Generic assessments for routine cleaning/disinfection
Main concerns:
- Protecting vulnerable patients as well as staff
- Latex allergy management
- Biological hazard control
- Waste disposal procedures
- Occupational health surveillance
Schools and education
Common hazardous substances:
- Cleaning products (often used by site staff)
- Science laboratory chemicals
- Art and DT materials (paints, solvents, resins, dusts)
- Swimming pool chemicals (chlorine, pH adjusters)
- Maintenance materials (paints, adhesives)
How many assessments?
- 3-5 generic assessments (cleaning, science, art/DT)
- Additional specific assessments for higher-risk activities
Main concerns:
- Protecting children and young persons
- Science demonstrations and practicals
- Ensuring teaching staff are competent to assess risks
- Contractor management (cleaners, maintenance)
Agriculture and horticulture
Common hazardous substances:
- Pesticides and herbicides
- Fertilisers
- Veterinary medicines
- Diesel and fuels
- Welding/cutting for equipment repair
- Organic dusts (grain, hay, animal waste)
How many assessments?
- 10-20 assessments covering different substances and tasks
- Specific assessments for pesticide application
- Biological hazard assessments (zoonoses, organic dusts)
Main concerns:
- Outdoor use (weather, wind drift)
- Storage of large quantities
- Spray application technique and drift control
- Re-entry intervals after pesticide use
- Occupational lung diseases (farmer's lung)
Frequently asked questions
Possibly. Many water-based products still contain hazardous ingredients. Check the label for hazard pictograms and the Safety Data Sheet. Products labelled as irritant, corrosive, or harmful require assessment, regardless of being water-based. If there are no hazard warnings, the product may not be hazardous enough to need assessment.
You can use it as a template or reference, but you must adapt it to your specific workplace, equipment, procedures, and workers. A COSHH assessment must reflect the actual risks and controls in your workplace. Simply copying another company's assessment won't be valid if inspected by HSE.
No. You need assessments for each hazardous substance or task. One assessment can cover multiple employees doing the same work with the same exposure and controls. However, if someone has particular vulnerabilities (pregnant, young person, known allergy), you may need to add specific considerations for them.
The cleaning contractor should have COSHH assessments for their work. However, you should check they have proper assessments and controls in place. If contractors work in occupied premises, coordinate so your employees aren't exposed to hazardous cleaning chemicals. Get copies of their assessments and safety data sheets.
Simple assessments for low-risk substances (common cleaning products used in small quantities): 15-30 minutes. Complex assessments for high-hazard substances or complex processes: 1-3 hours or more. Your first assessments take longer as you learn the process. Subsequently, updates are quicker.
If you're genuinely self-employed (not an employee working from home) and don't employ anyone, COSHH assessments are less critical unless you use significant hazardous substances. However, you should still assess risks to yourself and anyone else affected (family members, clients visiting). If you employ others, even home-based, you need proper assessments.
You need to assess all hazardous substances. However, you can group similar products into generic assessments where appropriate. Focus detailed effort on high-hazard substances (those with WELs, carcinogens, respiratory sensitisers). For numerous similar low-hazard products, create categories and assess by category rather than individually.
Infrequent use doesn't remove the need for assessment. However, the assessment can be simpler, and controls may be less elaborate if exposure is genuinely minimal. You still need to know what the hazards are, what controls are needed, and ensure anyone using the substance is competent and trained.
Yes. Directors, managers, and other officers can be prosecuted personally if an offence occurred with their consent, connivance, or was attributable to their neglect. If you knew COSHH assessments were required and failed to ensure they were done, you could face personal prosecution alongside the company.
Yes. HSE inspections can happen anytime, often following complaints, accidents, or routine targeting of high-risk industries. More importantly, COSHH assessments exist to protect your employees' health. Many occupational diseases develop slowly — by the time symptoms appear, damage is permanent. Compliance is about prevention, not just avoiding prosecution.
Next steps
To understand more about what COSHH covers and the compliance process:
To learn what information you need for assessments:
Safety Data Sheets: What They Are and How to Use Them →
To check whether specific substances are hazardous:
COSHH Substance Checker Tool →
Not sure if your COSHH assessments are adequate? A qualified health and safety consultant or occupational hygienist can assess your workplace, identify what assessments you need, and help you implement effective control measures.
Related articles:
- What is COSHH?
- Safety Data Sheets (SDS): What They Are and How to Use Them
- How to Conduct a COSHH Risk Assessment
Useful tools: