If you are an employer, or someone in control of premises, including landlords, you are responsible for health and safety risks associated with Legionella and need to take the right precautions to reduce the risks of exposure to Legionella bacteria. You must understand your duties under the Health and Safety at Work Act 1974 (HSWA) extend to risks from Legionella bacteria, which may arise from work activities.


All commercial, public buildings including rented and social residential buildings with a domestic hot or cold water system will require a Legionella risk assessment to be conducted on them to determine the level of risk associated with Legionella bacteria.

We provide site specific Legionella risk assessments following the methods and guidance laid out inThe Health and Safety Executive Approved Code of Practice, ‘Legionnaires’ Disease:  The control of Legionella bacteria in water systems’ (ACoP L8) and in compliance with:


  •  BS 8580:2010 Risk Assessments for Legionella Control- code of practice.

  • HSG274 part 2  The control of legionella bacteria in hot and cold water systems.

  • HSG274 Part 3  The control of Legionella bacteria in other water systems.

  • The water supply (water fittings) regulations 1999.


The assessment establishes if there are any areas of the system which could potentially promote the growth or exposure of Legionella bacteria to individuals within the premises.


Our risk assessments are undertaken by competent and experienced surveyors.  The assessments are extremely detailed and are easy to interpret.  The assessment identifies individual risks within a water system and explains why they may be a concern and how they can be resolved or controlled. 


Our risk assessment will include the following:


  • Inspection of all water outlets, including taps and showers

  • Temperature monitoring of hot and cold water outlets

  • Inspection of cold water storage tanks

  • Inspection of hot water cylinders and any plant which provide domestic hot water

  • Production of a water asset register

  • Schematic drawing of water systems

  • Inspection of configuration of system for risk factors, for example areas of stagnation and areas where water droplets are produced

  • Full recommendation list for non conformances

  • Identification of potentially susceptible personnel

  • Auditing of existing control regimes, site records and management of water systems


After the risk assessment Oasis will work with you to ensure there is an effective management programme in place for the control and prevention of Legionella bacteria and provide all training and guidance required.



Legionella Risk Assessment Reviews


This is a survey to establish if there have been any changes to the original Legionella risk assessment.  Risk assessments should be reviewed biennially as a minimum or:-


  • Wherever there is reason to suspect that the risk assessment is no longer valid.

  • Major changes to the water system or its use.

  • Changes to the use of the building in which the water system is installed.

  • The availability of new information about risks to control measures.

  • The results of checks indicating that control measures are no longer effective.

  • A case of Legionnaires disease / Legionellosis is associated within the system.


Legionella Risk Assessments And Reviews In Accordance With Acop L8 And HSG274