Legionella risk assessments

Assess and control the risk

Frequency: Review after relevant changes or concerns

The Health and Safety at Work etc. Act 1974 and the Control of Substances Hazardous to Health Regulations provide the framework for managing exposure risks, including relevant landlord responsibilities. HSE's Approved Code of Practice L8 and associated technical guidance explain approaches to assessing and controlling legionella risks. Responsibility depends on control of the premises and water systems, so clarify arrangements where management duties are shared.

There is no general legal requirement for landlords to buy a legionella certificate or commission routine water sampling for every domestic letting. The duty is to assess risk and implement suitable controls. A simple assessment may be sufficient for a small domestic system, particularly where water turns over regularly and there is little or no storage; more complex premises need a suitably competent approach.

Keep an appropriate record of findings, controls and responsibility for any monitoring. Review the assessment when systems, occupancy or use change, controls become ineffective or new information casts doubt on its conclusions. Check current HSE guidance, including landlord guidance, rather than assuming an annual certificate or a negative sample automatically satisfies the duty.

Practical controls for domestic water systems

Where temperature is the chosen control, HSE guidance generally calls for hot water stored at least at 60°C and distribution arranged so hot outlets reach at least 50°C within one minute. Some settings, including healthcare, have different targets. Cold water should generally remain below 20°C where practicable. Measurements and remedial decisions should reflect the actual system rather than a single reading taken without context.

Scald prevention matters, especially in supported accommodation and homes occupied by vulnerable people. Suitable thermostatic mixing arrangements may be needed close to outlets while maintaining appropriate upstream temperatures. Do not increase delivered tap temperatures indiscriminately. Remove redundant pipework or dead legs where practicable, maintain storage arrangements and include showerhead cleaning and descaling where appropriate to the assessed risk.

Manage empty rooms and changing occupancy

Low-use outlets, empty properties and unused sections of pipework can allow stagnation. A risk-based flushing programme can help, with weekly flushing commonly used for infrequently used outlets under HSE guidance. The method should minimise aerosol exposure and account for the system. Reoccupation after a long vacancy may need more than briefly running a kitchen tap, particularly where controls have not been maintained.

Record who carries out checks and what happens if temperatures or other conditions fall outside the plan. Give residents appropriate instructions without asking them to make unsafe adjustments. Peachtree can coordinate agreed plumbing improvements and monthly consolidated invoicing for agents, but ongoing water hygiene responsibilities should remain clearly assigned between visits.