Argonaut Heating - Legionella control services London, Essex, Kent and south east
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    Industrial and commercial heating, boiler replacement and plumbing services for London and the south east

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    Industrial and commercial air conditioning services for London and the south east

  • Argonaut Heating

    Air conditioning design, installation and maintenance for offices, schools and all building types in London, Essex, Kent and South East

  • Argonaut Heating

    Industrial and commercial heating design, installation, boiler replacements and maintenance for all building types

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Argonaut Heating Limited offers a specialised provision of Legionella Control services including water quality testing for our clients in the London, East Anglia and South East area including Essex, Suffolk, Cambridgeshire, Hertfordshire, Buckinghamshire, Berkshire, Bedfordshire, Middlesex, Surrey and Kent. 

We offer Legionella Risk Assessments, Legionella Testing and advice on legislative compliance with the Health and Safety Executive Approved Code of Practice (L8) - The control of legionella bacteria in water systems.

Legionnaires' Disease

Legionnaires’ disease is a potentially fatal form of pneumonia which can affect anybody. It is caused by the bacterium Legionella pneumophila and related bacteria. It is normally contracted by inhaling legionella bacteria, either in tiny droplets of water (aerosols), or in droplet nuclei (the particles left after the water has evaporated) contaminated with legionella, deep into the lungs.

Cases of Legionnaires’ disease have occurred among staff in the workplace (factories, offices, shops and hospitals); visitors (delivery drivers) and members of the public (patients, hotel guests or passers-by).

Legionella bacteria can survive under a wide variety of environmental conditions and have been found in water at temperatures between 6°C and 60°C. Water temperatures in the range 20°C to 45°C seem to favour growth. The organisms do not appear to multiply below 20°C and will not survive above 60°C. They may, however, remain dormant in cool water and multiply only when water temperatures reach a suitable level. Temperatures may also influence virulence; legionella bacteria held at 37°C have greater virulence than the same legionella bacteria kept at a temperature below 25°C.

The incubation period is between 2-10 days (usually 3-6 days). Infection with legionella bacteria can be fatal in approximately 12% of reported cases. This rate can be higher in a more susceptible population; for example, immuno-suppressed patients or those with other underlying disease. Certain groups of people are known to be at higher risk of contracting Legionnaires’ disease; for example, men appear more susceptible than women, as do those over 45 years of age, smokers, alcoholics, diabetics and those with cancer or chronic respiratory or kidney disease.

As legionella bacteria are commonly encountered in environmental sources they may eventually colonise manufactured water systems and be found in cooling tower systems, hot and cold water systems and other plant which use or store water. To reduce the possibility of creating conditions in which the risk from exposure to legionella bacteria is increased, it is important to control the risk by introducing measures which:

(a) do not allow proliferation of the organisms in the water system; and

(b) reduce, so far as is reasonably practicable, exposure to water droplets and aerosol.

Legionella Control

Many outbreaks of Legionnaires’ disease, if not all, are because of lack of training, poor management and incorrectly assessed premises.  Legionella Control is required wherever there is water used or stored, irrespective of size and usage.

It is a requirement under the Health and Safety Executive Approved Code of Practice (L8)  The control of legionella bacteria in water systems that you have a responsibility to comply with the legal requirements for the control of Legionellosis.

If any premises under your ownership or control has hot and cold water systems, then you have a responsibility to ensure that the risk is controlled and minimized at all times.

Where outbreaks have occurred, prosecutions have been taken under the Health & Safety at Work Act 1974, and under the Control of Substances Hazardous to Health Regulations 1988. Therefore compliance is essential. In order to do this, the recommendations of the Approved Code of Practice (L8) will have to be fulfilled.

This Approved Code of Practice applies to the control of legionella bacteria in any undertaking involving a work activity and to premises controlled in connection with a trade, business or other undertaking where water is used or stored and where there is a means of creating and transmitting water droplets which may be inhaled, thereby causing a reasonably foreseeable risk of exposure to legionella bacteria.

Experience has shown that cooling towers, evaporative condensers and hot and cold water systems in a wide variety of workplaces present a risk of exposure to legionella bacteria.  This includes schools, colleges, universities, hospitals, care homes, nursing homes, surgeries, dental practices, offices, hotels, shops and more.

Do I need to have a Risk Assessment?

If you have a water system that heats or cools water with the potential to create an aerosol then you will need a Risk Assessment.  Argonaut Heating Ltd offers a full Risk Assessment and advice service.

Risk Assessments are now required for ALL hot and cold water systems in the workplace, including:

  • Universities, Colleges & Schools
  • Hospitals and medical centres
  • Local authorities premises
  • Offices
  • Housing associations
  • Charities
  • Hostels
  • Landlords in the private renting sector
  • Managing agents
  • Hotels & Guest houses
  • Sports & Leisure Centres
  • Caravan and camp sites
  • Residential care homes and nursing homes
  • Doctors surgeries, dental practices
  • Food processing plants
  • Shops

Who controls the spread of Legionnaire's Disease?

To prevent an outbreak of Legionnaire's Disease ALL companies that operate water systems must comply with the regulations. These regulations require them to maintain, check, manage and treat any systems which could possibly cause the spread of Legionella.

A water system includes all plant/equipment and components associated with that system, e.g. all associated pipe-work, pumps, feed tanks, valves, showers, heat exchangers, quench tanks, chillers etc. It is important that the system is considered as a whole and not, for example, the cooling tower in isolation. Deadlegs and parts of the system used intermittently, for example test loops in engineering factories and injection moulding machines, also need to be included as part of the system since they can create particular problems with microbial growth going unnoticed. Once brought back on-line they can cause heavy contamination, which could disrupt the efficacy of the water treatment regime.

The current legislation stipulates the recommended inspection frequencies (weekly, monthly, annually) for the checks which have to be carried out on the various elements of the hot and cold water services.

Your duties under the Law

You have a number of duties to control the risks of legionella if:

  • You are an employer
  • You manage a premises with hot/cold water services (e.g. showers) and/or
  • You manage a premises with wet cooling systems (e.g. cooling towers and evaporative condensers)

Employers must consider the risks from legionella

The law requires that you consider the risks from legionella  that may affect your staff or members of the public and take suitable precautions.  As an employer or a person in control of the premises (e.g. a landlord), you must:

  • Have a Risk Assessment carried out by our qualified team who will identify and assess sources of risk;
  • Prepare a scheme, or course of action, for preventing or controlling the risk;
  • Implement and manage the scheme - appointing a person to be managerially responsible, sometimes referred to as the 'responsible person';
  • Keep records and check that what has been done is effective;
  • If appropriate, notify the local authority that you have a cooling tower(s) on site

What records need to be kept?

If you employ five or more people you must record the significant findings of your Risk Assessment.  This means writing down the significant findings of the assessment and details of any monitoring or checking carried out.

If you have fewer than five employees you do not need to write anything down, although it is useful to keep a written record of what you have done.  You also need to keep records of your written scheme and who is responsible for managing that scheme.  You should also keep the results of your routine monitoring.  You need to keep these records for a minimum of five years.

Legionella Risk Assessment and Water Quality Testing Services 

For further information on your duties under the Law, please go to our water quality testing information page

Contact us 

Contact Argonaut Heating Ltd for further information on our specialised Legionella Control services