Health and Safety at Work etc. Act 1974
Updated 16 August 2026
Summary
The Health and Safety at Work etc. Act 1974 is the foundation of all UK workplace health and safety law. For legionella, it is the Act that creates the duty to assess and control the risk. ACOP L8 and HSG274 are both published under its authority and explain how the general duties apply to water systems specifically.
What it does
The Act imposes general duties that are expressed in broad terms and made concrete through secondary legislation, approved codes of practice, and guidance. For legionella, the most important sections are:
- Section 2: duty of employers to ensure the health, safety, and welfare at work of their employees, so far as is reasonably practicable
- Section 3: duty of employers and self-employed people to conduct their undertaking so that non-employees (including tenants, visitors, and members of the public) are not exposed to risks to their health and safety
- Section 4: duty of those in control of non-domestic premises to ensure the premises and any means of access or plant or substance are safe for people not in their employment who use them
These three sections together capture almost every situation where someone might be exposed to legionella from a non-domestic water system. Section 3 in particular is the one most commonly cited in landlord prosecutions.
Who it applies to
The Act applies to all employers, self-employed people, and anyone in control of non-domestic premises in Great Britain. Northern Ireland has equivalent legislation under the Health and Safety at Work (Northern Ireland) Order 1978.
Free legionella risk assessment template
A structured Word document following the five-step approach in ACOP L8. Covers risk identification, written scheme, monitoring, and records. If it isn't written down, you can't evidence it.
Follows ACoP L8 and HSG274 Part 2. Free. No spam.
Key obligations
The general duties are qualified by the test of what is "reasonably practicable". This means the measures required must be proportionate to the risk. For a simple domestic let, the obligation is light. For a large care home or hospital, it is extensive. The written assessment is the mechanism by which that proportionality is demonstrated.
Penalties for non-compliance
Breach of the general duties is a criminal offence. On summary conviction in the magistrates' court the fine is limited; on conviction on indictment in the Crown Court the fine is unlimited. Directors, managers, and company secretaries can be personally prosecuted under section 37 where an offence by the organisation is shown to have been committed with their consent, connivance, or as a result of their neglect.
Read the full text: Health and Safety at Work etc. Act 1974 on legislation.gov.uk
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Free legionella risk assessment template
A structured Word document following the five-step approach in ACOP L8. Covers risk identification, written scheme, monitoring, and records. If it isn't written down, you can't evidence it.
Follows ACoP L8 and HSG274 Part 2. Free. No spam.