Your Responsibilities
Your duties under Health & Safety at Work At 1974 (HSWA) and Document HSG 274 extend to risks from legionella bacteria, which may arise from work actives. The management of Health and Safety at Work regulation (MHSWR) provide a broad framework for controlling health and safety at work. More specifically the control of substances hazardous to Health Regulations 2002 (COSHH) provide a framework of duties designed to assess, prevent or control the risk from bacteria like legionella and take suitable precautions.
For further information please click on link
http://www.hse.gov.uk/legionnaires/
Are there legionella risks in my workplace? Any water system, with the right environmental conditions , could be a source for legionella bacteria growth. There is a reasonably foreseeable legionella risk if your water system;
Has a water temperature between 20-45 C Creates and/or spreads breathable droplets, e.g. aerosol created by a cooling tower, or water outlet Stores and/or re-circulates water Likely to contain a source of food for the organism, e.g. presence of sludge, scale There are also a number of other systems that may pose a risk to exposure to Legionella, e.g. humidifiers, air washers, emergency showers, indoor ornamental fountains etc.
If you are an employer, or someone in control of premises (e.g. a landlord), you have a duty of care to manage legionella risks.
Your Responsibilities Your duties under the Health & Safety at Work Act 1974 (HWSA) and Document HSG 274 extend to risks from legionella bacteria, which may arise from work actives. The management of Health and Safety at work and more specifically the Control of Substances Hazardous to Health Regulations 2002 (COSHH) provide a framework of duties designed to assess, prevent or control the risk from bacteria like legionella and take suitable precautions.
As an Employee, or a person in control of the premises, you are responsible for health and safety and need to take the right precautions to reduce the risks of exposure to legionella.
You must understand how to:
Identity and assess sources of risk Manage any risk Prevent or control any risks keep the correct records. 
