If you have ever walked into a workplace bathroom and spotted a bottle labeled “hazardous” or pulled on a pair of gloves before mixing cleaning solutions, you have already brushed up against COSHH. But what does that acronym actually stand for, and why does it matter to nearly every UK employer? This guide unpacks the regulation itself, the substances it covers, and the practical duties it places on businesses — down to the letter of the law.

4 related posts

Regulation full name: Control of Substances Hazardous to Health ·
Year first introduced: 1988 ·
Latest amendment: 2020 ·
Enforcing body: Health and Safety Executive (HSE)

Quick snapshot

1What is COSHH?
2Substances Covered
3Key Requirements
4Timeline Signal
  • 1988: First COSHH Regulations introduced in UK
  • 2002: Revised COSHH Regulations (SI 2002/2677)
  • 2020: Latest amendment aligning with EU CLP changes

The pattern across these four cards is clear: COSHH is a fixed legal framework that has been updated only sparingly over three decades.

Four key facts, one pattern: COSHH is a fixed legal framework that has been updated only sparingly over three decades.
Label Value
Full form Control of Substances Hazardous to Health
Year introduced 1988
Enforced by Health and Safety Executive (HSE)
Main requirement Employers must prevent or adequately control exposure to hazardous substances

What is COSHH and what does it stand for?

What does COSHH stand for?

  • C — Control
  • O — Of
  • S — Substances
  • H — Hazardous
  • H — To Health (British Safety Council (UK health and safety training body))

COSHH is a set of UK regulations requiring employers to control exposure to hazardous substances, enforced by the Health and Safety Executive (HSE) (Health and Safety Executive (HSE) (UK government regulator)). Breach of these regulations by employers or employees is a crime punishable by an unlimited fine (British Safety Council (UK health and safety training body)).

The COSHH Regulations derive their authority from the Health and Safety at Work etc. Act 1974. They replace earlier, piecemeal legislation covering specific substances and create a single framework for all hazardous substances in the workplace. The regulations apply to substances in liquid, solid, or gas form that can cause harm (Mintra).

The upshot

COSHH is not optional guidance — it sits directly under primary legislation. Any UK employer who ignores it faces legal liability, not just a compliance headache.

The implication: COSHH is the mechanism through which the HSE enforces workplace health, not a standalone suggestion.

What is a substance hazardous to health?

How does the HSE define a substance hazardous to health?

A substance hazardous to health is any substance that can cause harm to a person’s health through exposure (Health and Safety Executive (HSE) (UK government regulator)). COSHH covers chemicals, biological agents, dusts, fumes, and other airborne particles (Health and Safety Executive (HSE)).

What are examples of hazardous substances?

  • Cleaning products used in offices, hospitals, and factories (Health and Safety Executive (HSE) (UK government regulator))
  • Paints and varnishes containing solvents (Mintra)
  • Welding fumes generated in fabrication shops (Mintra)
  • Infectious bacteria and viruses in healthcare settings (Health and Safety Executive (HSE) (UK government regulator))
Why this matters

The breadth of what COSHH covers means almost every UK workplace touches at least one hazardous substance — often without realizing it. A cleaning cupboard is as regulated as a chemical plant.

The catch: the same everyday items that seem harmless (spray bleach, toner cartridges, glues) fall under COSHH if they can cause harm through inhalation, skin contact, or ingestion.

What are the main substances covered by COSHH?

What are the five categories of COSHH substances?

  • Chemicals: acids, solvents, pesticides (Mintra)
  • Biological agents: bacteria, viruses, fungi (Mintra)
  • Dusts: silica dust, wood dust, grain dust (Health and Safety Executive (HSE) (UK government regulator))
  • Fumes: welding fumes, soldering fumes (Mintra)
  • Vapours: paint thinners, cleaning solvent vapours (Mintra)

What is included in each category?

Chemicals include acids, solvents, and pesticides — these are the most common COSHH-relevant materials in manufacturing, agriculture, and maintenance (Mintra). Biological agents include bacteria, viruses, and fungi — relevant in healthcare, laboratories, and waste management (Health and Safety Executive (HSE) (UK government regulator)). Dusts like silica dust from construction and wood dust from joinery are covered, as are fumes from welding and soldering (Health and Safety Executive (HSE)). Vapours from paint thinners and cleaning solvents round out the list.

The trade-off

The five categories are broad enough to capture most workplace hazards, but the regulation’s reliance on “hazardous to health” as a threshold means borderline cases — for instance, nanomaterials — exist in a grey area.

The pattern: COSHH’s categories mirror the physical forms in which substances reach workers — if it can be breathed, swallowed, or absorbed, it is likely covered.

What substance isn’t covered by COSHH?

Which hazardous substances are not covered by COSHH?

Substances that are covered by other specific regulations (e.g., lead, asbestos, radioactive substances) are generally not covered by COSHH (Health and Safety Executive (HSE) (UK government regulator)). Cosmetic products used for personal care, such as shampoo or hand cream, are not covered. Substances that are solely a fire or explosion hazard — without being toxic or harmful to health — are also excluded.

What is the difference between COSHH and other regulations?

The Control of Asbestos Regulations 2012 governs asbestos. The Ionising Radiations Regulations 2017 covers radioactive substances. The Dangerous Substances and Explosive Atmospheres Regulations 2002 (DSEAR) handles fire and explosion risks from chemicals. COSHH fills the gap for everything else that can harm health through exposure (Health and Safety Executive (HSE) (UK government regulator)).

The implication: COSHH is less a standalone rulebook and more part of a regulatory patchwork. Employers must know which regulation applies to each substance.

What are COSHH regulations?

What are the three basic rules of COSHH?

  • Identify hazards — find out which hazardous substances are present (Health and Safety Executive (HSE) (UK government regulator))
  • Assess risks — evaluate who could be harmed and how likely harm is (Mintra)
  • Control exposure — implement measures to prevent or reduce exposure (Health and Safety Executive (HSE) (UK government regulator))

What are the five principles of good control practice?

According to the HSE, the principles of good control practice include: design and operate processes to minimise emission; control exposure at source; provide PPE only as a last resort; maintain and examine control measures; and provide information and training (Health and Safety Executive (HSE) (UK government regulator)). Note that the HSE’s current guidance lists eight principles in total, but the five listed here form the core.

Bottom line: COSHH is a legal framework, not a suggestion. For UK employers: start with the risk assessment, then implement controls. For employees: follow the training and use the equipment provided. For self-employed workers: yes, COSHH applies to you too.

The catch: the exact number of principles varies depending on whether you count the HSE’s original five or its expanded eight-point list — a minor inconsistency that does not change the practical obligations.

Why is COSHH important?

How many requirements does COSHH place on the employer?

  • Carry out a risk assessment (Health and Safety Executive (HSE) (UK government regulator))
  • Prevent or adequately control exposure (Health and Safety Executive (HSE) (UK government regulator))
  • Implement, maintain, and monitor control measures (British Safety Council (UK health and safety training body))
  • Provide information, instruction, and training (British Safety Council (UK health and safety training body))
  • Establish procedures for accidents and emergencies (British Safety Council (UK health and safety training body))
  • Provide health surveillance where needed (British Safety Council (UK health and safety training body))
  • Ensure exposure levels remain below Workplace Exposure Limits (WELs) (Rippling (business compliance platform))
  • Maintain records of risk assessments and health surveillance

What are the consequences of non-compliance?

Breach of COSHH regulations by employers or employees is a crime punishable by an unlimited fine (British Safety Council (UK health and safety training body)). Beyond fines, non-compliance can result in prosecution, reputational damage, and in severe cases, imprisonment. The HSE can issue prohibition notices and improvement notices that stop work activities immediately.

How do the 7 common workplace hazards relate to COSHH?

Common workplace hazards often have a COSHH dimension. Cleaning products contain chemicals that can irritate skin or damage lungs. Dusts from construction or woodworking create respiratory risks. Fumes from welding or soldering contain metal oxides harmful to health. The seven basic safety rules — identify, assess, control, train, monitor, review, record — mirror the COSHH process closely.

What to watch

The HSE reports that occupational lung disease alone costs the UK economy billions annually. COSHH is the primary tool to prevent those cases — yet many smaller businesses still treat it as paperwork, not protection.

For UK employers, the choice is clear: invest in a compliant COSHH assessment now, or face the consequences of a substance exposure incident later.

Timeline: Evolution of COSHH Regulations

  • — First COSHH Regulations introduced in the UK, replacing piecemeal legislation
  • — COSHH (Amendment) Regulations brought minor updates
  • — Revised COSHH Regulations (SI 2002/2677) implemented, introducing the current risk-assessment framework
  • — Latest amendment aligning with EU CLP (Classification, Labelling and Packaging) changes

The timeline is relatively stable, with only three major revisions in over thirty years. The 2020 amendment was largely technical, reflecting chemical classification updates rather than a change in regulatory philosophy.

Timeline signal

The consistency of COSHH’s core framework since 2002 means that employers can rely on established guidance — they do not face annual regulatory churn.

Confirmed facts about COSHH

  • COSHH stands for Control of Substances Hazardous to Health (British Safety Council)
  • COSHH requires a risk assessment for hazardous substances (Health and Safety Executive (HSE))
  • Five main categories of substances are covered: chemicals, biological agents, dusts, fumes, and vapours (Mintra)
  • Breach of COSHH is a criminal offence punishable by unlimited fine (British Safety Council)

What’s unclear about COSHH

  • The exact number of principles of good control practice — some sources say five, but the HSE currently lists eight (Health and Safety Executive (HSE))
  • Whether certain emerging substances (e.g., nanomaterials) are explicitly covered under existing definitions (Mintra)

Expert perspectives on COSHH

A substance hazardous to health is any substance that can cause harm to a person’s health through exposure. COSHH covers chemicals, biological agents, dusts, fumes, and other airborne particles.

Health and Safety Executive (HSE) (UK government regulator)

COSHH stands for ‘Control of Substances Hazardous to Health’. Employers must prevent or adequately control exposure to hazardous substances.

British Safety Council (UK health and safety training body)

No work involving hazardous substances can begin until a COSHH-compliant risk assessment is completed.

Rocket Lawyer (UK legal document provider)

COSHH applies to substances in liquid, solid, or gas form that can cause harm.

Mintra (workforce safety training provider)

Summary

COSHH is the legal backbone of workplace health protection in the UK, covering everything from everyday cleaning products to industrial fumes. The regulation demands prevention first, control second, and personal protection only as a last resort. For UK employers, the implication is clear: conduct a proper COSHH risk assessment now, or face the consequences of a substance exposure incident later.

Additional sources

trainingexpress.org.uk, skillsforhealth.org.uk, skillcast.com

Don't miss these

Frequently asked questions

What are COSHH symbols?

COSHH symbols are pictograms that indicate the type of hazard a substance presents. Common symbols include the exclamation mark for irritants, the skull for toxic substances, and the flame for flammable materials. These symbols are based on the Globally Harmonized System (GHS) and are required on product labels (Health and Safety Executive (HSE) (UK government regulator)).

What does COSHH training involve?

COSHH training covers how to identify hazardous substances, read safety data sheets, use control measures correctly, and respond to incidents. The HSE requires all relevant employees to receive instruction and training (British Safety Council (UK health and safety training body)).

How often should a COSHH assessment be reviewed?

There is no fixed legal interval, but the HSE recommends reviewing a COSHH assessment whenever there are significant changes — new substances, new processes, or if exposure monitoring reveals problems. Annual review is widely considered best practice (Health and Safety Executive (HSE) (UK government regulator)).

What is a COSHH assessment sheet?

A COSHH assessment sheet is a document that records the hazards, risks, and control measures for each hazardous substance in a workplace. It typically includes the substance name, how it is used, who could be harmed, and what controls are in place. The HSE provides downloadable templates (Health and Safety Executive (HSE) (UK government regulator)).

Are cleaning products covered by COSHH?

Yes, cleaning products that contain hazardous chemicals such as bleach, ammonia, or solvents are covered by COSHH. Employers must assess the risks, provide training, and ensure appropriate controls such as gloves and ventilation are used (Health and Safety Executive (HSE) (UK government regulator)).

Does COSHH apply to self-employed workers?

Yes, since 2015, the COSHH Regulations apply to self-employed workers whose work poses a risk to their health or the health of others. Self-employed people who use hazardous substances must manage their own exposure and ensure they are trained (Health and Safety Executive (HSE) (UK government regulator)).

What is the difference between COSHH and DSEAR?

COSHH covers substances hazardous to health (toxic, corrosive, carcinogenic, etc.), while DSEAR (Dangerous Substances and Explosive Atmospheres Regulations 2002) covers substances that pose a fire or explosion risk. A substance that is both toxic and flammable would fall under both sets of regulations (Health and Safety Executive (HSE) (UK government regulator)).

Related reading