Legionella Risk Assessment in Croydon

Legionella bacteria thrive in water temperatures between 20°C and 45°C, in stagnant water, and where there is biofilm, rust, scale, or sediment providing nutrients. Systems most at risk include those with dead legs (unused pipe runs), infrequently used outlets, storage tanks without lids, and water systems where the hot water is not stored at 60°C or above. The assessment identifies these risk factors in your specific property.

There is no fixed legal frequency, but the HSE recommends reviewing the assessment at least every two years, or sooner if there is a change to the water system, the building use changes, the results of monitoring suggest problems, or a case of Legionnaires' disease is linked to the building. For higher-risk buildings such as care homes and hotels, annual reviews are standard practice.

The assessor examines all hot and cold water systems, including boilers, cylinders, storage tanks, calorifiers, showers, taps, and any associated pipework. They check water temperatures at sentinel outlets (nearest and furthest from the heat source), look for dead legs or rarely used outlets, inspect tank lids and insulation, review the system schematic, and assess whether current controls are adequate to prevent bacterial growth.

No. A risk assessment is an inspection-based evaluation of the water system's design, condition, and management, resulting in a written report with control recommendations. Legionella testing (water sampling) involves taking water samples and sending them to a UKAS-accredited laboratory to detect the actual presence and concentration of Legionella bacteria. Testing may be recommended by the risk assessment but is a separate service.

Yes. The HSE can prosecute landlords who fail to assess and control the risk of Legionella under the Health and Safety at Work etc. Act 1974. Prosecution cases have resulted in significant fines and, in cases involving death or serious illness, custodial sentences. Even where no illness occurs, failure to have a documented risk assessment is itself a breach that can lead to enforcement action.

Croydon Council has been particularly active in HMO licensing enforcement and has an Additional Licensing scheme covering parts of the borough. Landlords operating HMOs in Croydon should expect scrutiny on fire alarm standards and fire risk assessments as a condition of their licence. The general legal requirements for legionella risk assessment apply across England, but London Borough of Croydon may have additional conditions attached to property licences or local enforcement priorities that affect how the requirements are applied in practice.

Croydon's housing stock spans Victorian and Edwardian terraces in areas like South Norwood and Thornton Heath, inter-war semis around Purley and Sanderstead, post-war council estates in New Addington, and large-scale modern regeneration near East Croydon station. The borough has one of the highest concentrations of HMOs in South London, particularly in the CR0 postcode area. Common property types that require this service include HMOs, converted Victorian terraces, purpose-built council blocks, modern new-build flats. The specific requirements depend on the property type, tenure, and how the building is used.