The Control of Legionella and Legionellosis in Scotland

Our water services throughout Scotland will be routinely checked and inspected, and should be well maintained. The frequency of inspection and maintenance will depend on the system and the risk it presents. For most systems in stable operation it will be sufficient to inspect and check the following:

• Conditions in tanks, for the presence of organic materials, vermin, etc. (annually or more frequently if there is reason to suspect contamination);

• Conditions in calorifiers, for organic materials and unduly heavy build of scale (annually)

• The condition of accessible pipework and insulation (annually)

Legionella Control
   

The system will require more frequent inspection and checking if it is not in stable operation, eg., because of poor supply water quality, inadequate enclosure of tanks or faulty operation of plant. More frequent inspection we supply to our customers around Scotland will include checking where necessary in buildings where there is a high risk.

   
Legionellosis Control

Water service should be disinfected before being taken into use to remove contamination which may have occurred during construction, or during repair and alteration to external pipework, in accordance with the British Standard 6700 specification for the design, installation, testing and maintenance of services supplying water for domestic use within buildings and their curtilages. This is for purposes other than the control of legionella.

   

Hot and Cold Water Services

Legionella Control Services

1. Carry out risk assessment

2. Drain down and clean tank

3. Paint tank if metal, using suitable paint

4. Chlorinate, tank and dose system at 50ppm

5. Take water samples for analysis

6. Reinstate water system

7. Legislation and maintenance (see below)


Legislation for the Control of Legionella

1. Duties under the Health and Safety at Work etc Act 1974 extend to risks from legionella arising from work activities. More specifically, the Control of Sustances Hazardous to health Regulations 1988 (COSHH) relate to the risks from hazardous micro-organisms, including legionella and chemicals such as biocides and chlorine. Under these Regulations risk assessment and the adoption of appropriate precautions are required.

2. The Approved Code of Practice (ACOP) The prevention or control of legionellosis (including legionnaires’ disease) gives practical guidelines on the standards that must be met in order to comply with the legal requirements for dealing with this risk. The ACOP applies wherever water is stored and used in a way which may create a reasonably foreseeable risk of legionellosis and in particular to the following plant and systems where the Health and Safety at Work etc. Act 1974 applies.

3. The ACOP explains that in order to comply with their legal duties, employers and others should:

a. identify and assess the sources of risk;
b. prepare a scheme for preventing or controlling the risk;
c. implement and manage precautions;
d. keep records of the precautions implemented.

4. The ACOP also sets out the responsibilities of manufacturers, importers, suppliers and installers of products and services. The statutory requirements are enforced by Health and Safety Executive inspectors in factories, hospitals, laboratories, education establishments, docks and construction sites. As well as in shops, offices, warehouses, hotel and catering establishments. They are enforced by local authorities who also have responsibilities for public health. Past outbreaks of legionnaires’ disease in the UK have demonstrated the implications for public health.

5. Some of the control measures required by the legislation (in combination with the ACOP) have to be applied ‘so far as is reasonably practical’. This means that in determining what measures should be taken, or to what extent, the degree or risk of legionellosis should be weighed against the cost and difficulty of applying the measures in question. On balance the benefits of adopting a particular method or system (ie., the reduction of risk) should outweigh the costs involved.

Routine Inspection and Maintenance

6. Water services should be routinely checked and inspected, and should be well maintained. The frequency of inspection and maintenance will depend on the system and the risk it presents. For most systems in stable operation it will be sufficient to inspect and check the following:

a. Conditions in tanks, for the presence of organic materials, vermin, etc. (annually or more frequently if there is reason to suspect contamination);
b. Conditions in calorifiers, for organic materials and unduly heavy build of scale (annually);
c. The condition of accessible pipework and insulation (annually).

7. The system will require more frequent inspection and checking if it is not in stable operation, eg., because of poor supply water quality, inadequeate enclosure of tanks or faulty operation of plant. More frequent inspection and checking will also be necessary in buildings where there is a high risk.

Cleaning and Disinfection in Scotland

8. Water service should be disinfected before being taken into use to remove contamination which may have occurred during construction, or during repair and alteration to external pipework, in accordance with the British Standard 6700 specification for the design, installation, testing and maintenance of services supplying water for domestic use within buildings and their curtilages. This is for purposes other than the control of legionella. For more information about our legionellosis control services throughout Scotland please don’t hesitate to contact us today.