COSHH Regulation 7: The Adequate Control Duty Explained

What Is COSHH Regulation 7?

Regulation 7 of the Control of Substances Hazardous to Health Regulations 2002 is the core enforcement obligation for UK employers. It sets out the duty to prevent or control exposure to hazardous substances — and it is the regulation most likely to be cited in enforcement action when a workplace fails to protect employees from chemical or biological risks.

The full title of Regulation 7 is "Prevention or control of exposure to substances hazardous to health." It sits at the centre of COSHH compliance: your risk assessments (Regulation 6) tell you what the risks are, and Regulation 7 tells you what you must do about them.

The Core Duty: Regulation 7(1)

Regulation 7(1) states:

"Every employer shall ensure that the exposure of his employees to substances hazardous to health is either prevented or, where this is not reasonably practicable, adequately controlled."

This sets a two-stage obligation:

First, prevent exposure — eliminate the substance or substitute it with something less hazardous.
If prevention is not reasonably practicable, adequately control exposure — using the hierarchy set out in Regulation 7(3).

The order matters. Employers cannot jump straight to PPE. The law requires you to consider prevention first.

Prevention: Regulation 7(2)

Regulation 7(2) specifies what prevention means in practice: employers must avoid using hazardous substances by substituting them with safer alternatives where this is reasonably practicable.

Common examples:

Replacing a solvent-based paint with a water-based equivalent
Switching from a strong acid descaler to a mildly acidic alternative for routine limescale removal
Using pre-dampened wipes instead of a spray product that generates airborne mist

If substitution is genuinely not possible — because there is no effective alternative, or the safer alternative compromises product quality or process integrity — you move to the control hierarchy.

The Hierarchy of Control: Regulation 7(3)

Where exposure cannot be prevented, Regulation 7(3) sets out the measures you must apply, in priority order:

(a) Engineering controls and work process design

Design the work process to minimise exposure at source:

Enclosed or partially enclosed processes (e.g. enclosing a grinding operation)
Local exhaust ventilation (LEV) — extracting fume, vapour, or dust at the point of generation before it reaches the employee's breathing zone
Automated dispensing to reduce manual handling of concentrates
Water suppression on cutting and drilling tools to suppress dust before it becomes airborne

(b) Organisational and administrative controls

Reduce exposure through how work is organised:

Limiting the number of workers exposed
Reducing the duration and frequency of exposure
Safe systems of work — defining how tasks are done to minimise contact
Maintaining adequate general ventilation
Providing appropriate hygiene measures (designated wash facilities, prohibiting eating in work areas)

(c) Personal protective equipment (PPE)

RPE and other PPE is always the last resort, not the first line of defence. Regulation 7(3)(c) states that PPE is provided only "where adequate control of exposure cannot be achieved by other means."

This hierarchy has direct regulatory force: an employer who relies on PPE alone without first considering engineering controls is not complying with Regulation 7, regardless of whether the PPE is appropriate for the hazard.

When Is Control "Adequate"? Regulation 7(7)

"Adequate control" has a specific legal meaning under Regulation 7(7). Exposure is adequately controlled only if:

The good practice principles in Schedule 2A of the Regulations are applied
Workplace Exposure Limits (WELs) are not exceeded — WELs are published in the HSE's EH40 document and represent the maximum concentration of a substance in the air that workers may breathe over an 8-hour shift (or 15 minutes for short-term limits)
For carcinogens, mutagens, and asthmagens: exposure is reduced to as low as reasonably practicable (ALARP) — simply keeping below the WEL is not enough for these substance classes

This three-part test means that compliance with a WEL alone does not automatically satisfy Regulation 7 — you must also apply good practice principles and, for high-hazard substances, push exposure as low as reasonably achievable.

Additional Requirements for Carcinogens and Mutagens: Regulation 7(5)

Where work involves substances that are carcinogenic or mutagenic, Regulation 7(5) imposes additional controls beyond the standard hierarchy:

Total enclosure of processes where technically practicable
Prohibition on eating, drinking, and smoking in contaminated areas
Regular cleaning of floors, walls, and surfaces in contaminated areas
Designated areas with appropriate warning signs
Safe storage of carcinogens and mutagens in closed, clearly labelled containers

This applies to any carcinogenic substance — not just those with high acute toxicity. Wood dust (hardwood), silica dust, benzene, and all welding fume fall within this requirement following the HSE's 2019 reclassification of mild steel welding fume as a carcinogen.

Regulation 7 and Local Exhaust Ventilation

LEV is often the preferred engineering control under Regulation 7(3)(a) for processes that generate airborne hazards — grinding, welding, cutting, mixing. An LEV system that is installed but not working is not a control: Regulation 9 requires thorough examination and testing of LEV at least every 14 months, with a written record kept for at least 5 years.

If your LEV is due for testing, the Regulation 7 adequacy requirement means this is not optional: an untested system cannot reliably demonstrate adequate control. For a detailed guide to LEV testing requirements, see our LEV testing and COSHH guide.

Practical Steps to Meet Regulation 7

For most UK SMEs, meeting Regulation 7 in practice comes down to:

Have a current COSHH assessment (Regulation 6) — you cannot know whether control is adequate without first assessing the risks.
Work through the hierarchy — start with elimination/substitution, then engineering controls, then PPE. Document your reasoning if you skip a tier (e.g. "substitution not reasonably practicable because no water-based alternative meets the performance specification").
Check WELs for every substance — if your substance has a WEL, consider whether monitoring is needed to verify control. For many routine SME situations, a reasoned judgement without air monitoring is defensible; for higher-hazard situations, you may need professional exposure monitoring.
Apply ALARP for carcinogens and asthmagens — being below the WEL is not enough. You must also be actively working to push exposure lower where reasonably achievable.
Maintain your controls — controls that are not maintained are not controls. Check LEV systems are functioning, replace PPE when worn, ensure ventilation systems are operational.
Review when circumstances change — a new substance, a changed process, or a new supplier can alter the control adequacy picture. Regulation 7 is a continuing duty, not a one-off exercise.

Why Regulation 7 Matters for Enforcement

When the HSE investigates a work-related illness or carries out a proactive inspection, Regulation 7 is the primary lever. Inspectors assess whether:

Prevention was properly considered before defaulting to control
The hierarchy of control was followed (engineering before PPE)
WELs are being met for substances where limits apply
Carcinogens and asthmagens are controlled to ALARP
Controls are maintained and effective

Failures on any of these grounds can result in improvement notices (requiring action within a set deadline), prohibition notices (stopping work immediately), and in serious cases, prosecution under the Health and Safety at Work etc. Act 1974.

Understanding Regulation 7 is the foundation for understanding whether your COSHH programme is genuinely effective — or just compliant on paper.

This guide is for information only and does not constitute legal advice. The definitive text is COSHH Regulation 7 and the HSE Approved Code of Practice L5.