What is ACoP L8?
Legionnaires' disease: The control of legionella bacteria in water systems, known as ACoP L8, is HSE's Approved Code of Practice. The current fourth edition was published in 2013. It has special legal status: if you do not follow it, you must be able to show that you have complied with the law in another equally effective way.
What is HSG274?
HSG274 is HSE's technical guidance that sits alongside L8. It has three parts:
- Part 1: evaporative cooling systems such as cooling towers
- Part 2: hot and cold water systems, which covers most buildings
- Part 3: other risk systems, including spa pools, humidifiers and vehicle washes
Duty holder and responsible person
The duty holder is the employer or person in control of the premises. They carry the legal responsibility. The duty holder should appoint a responsible person, someone with sufficient authority, competence and knowledge of the installation, to manage day-to-day control. That person may be supported by a competent contractor.
The written scheme of control
Where a risk is identified, you need a written scheme that explains how the risk is controlled. It should include an up-to-date schematic of the system, the control measures, the checks to be carried out and how often, and what to do if results go out of range.
Typical HSG274 Part 2 checks
| Task | Typical frequency |
|---|---|
| Flush little-used outlets | Weekly |
| Sentinel outlet temperatures | Monthly |
| Calorifier flow and return temperatures | Monthly |
| Clean and descale shower heads and hoses | Quarterly, or as needed |
| Cold water tank temperature and condition | Every six months to annually |
| Representative outlet temperatures on a rotational basis | Annually |
| TMV in-service checks | At least annually |
| Calorifier inspection and drain | Annually |
Your own risk assessment may set different frequencies depending on the system and the people at risk.
Record keeping
Records should be kept for at least five years. That includes the risk assessment, the written scheme, monitoring and inspection results and details of remedial work. Our digital log books make this simple.
Frequently asked questions
Is ACoP L8 a law?
ACoP L8 is not law itself, but it has special legal status. Following it is usually enough to show compliance with the law on legionella.
How long should legionella records be kept?
At least five years.
Disclaimer: This guide is general information about UK requirements and is not legal advice. Always check the current legislation and guidance for your premises.