Legionella Risk Assessment

The risk from exposure to legionella bacteria is associated with the following systems;

Water systems incorporating a cooling towers and/or evaporative condensers:

Hot and cold water systems;

Water systems where water temperature exceeds 20˚C and there is also a likelihood of aerosol release during operation.

 

The risk from exposure to legionella bacteria is dependent on the following factors:

The presence of the bacteria in the water;

Environmental conditions which are favourable for the growth of the bacteria e.g. food and temperature;

A method by which contaminated water can form into breathable droplets e.g. from a shower head

The number of persons who may be particularly susceptible to the ill effects of the bacteria if exposed to contaminated droplets e.g. in healthcare premises.

 

The above factors form the basis of the Core Surveys Ltd legionella risk assessment.  Where any of these risk factors from legionella are present, further investigation is required.  The nature of the site and the complexity of the water system will impact on the level of assessment required. 

The Core Surveys Ltd standard legionella risk assessment is designed in such a way as to incorporate all the guidance contained within L8, but is tailored to the individual needs of the client, to ensure that the client is doing everything reasonably practicable to control the risk of legionella.  All risk assessments are carried out by trained and experienced consultants qualified by the Water Management Society to advanced risk assessor level as a minimum.  Our consultancy process includes the following:

Initial meeting or discussion regarding the level of risk and the type of systems;

Agreement on the content of the risk assessment and how it is to be presented;

Time frame for completion of work.

 

As a minimum our legionella risk assessment will include the following sections:

introduction to legionella bacteria and the relevant legislation

a basic description of all the water services present and and identification of particular risk systems in table format

condition survey reports of all system components such as cold water tanks, calorifiers, showers etc

appraisal of the current management procedures including training

a risk evaluations summary

comprehensive recommendations for future control measures in order that the risk is, or continued to be minimised

photographic evidence of the condition of systems

asset register detailing all plant associated with the water system

basic schematic drawings of the water system

glossary of terms used within the risk and associated documents

 

The aim of the legionella risk assessment is to provide a foundation for controlling the risk but it is by no means the end of the management process.  If the risk assessment identifies a foreseeable risk of legionella, a scheme for controlling these risks will be required.