Legionnaires’ disease is a potentially fatal form of pneumonia. It is caused by the legionella bacteria which can develop in any system where water is stored at temperatures favourable to its growth; water tanks, calorifiers, hot and cold-water systems, pools and spas.

On caravan and holiday parks, the statutory duty holder for the premises is responsible for making sure the site is risk assessed, and ensuring that regular checks are carried out to prevent the conditions occurring that might allow the bacteria to grow. Failing to comply can result in serious health implications and even death in some cases. Businesses also risk severe fines or, in the worst cases, prosecution for involuntary manslaughter.

Fortunately, the risk from legionella bacteria can be reduced and managed simply and effectively by taking the correct preventative actions including: 

1. Carrying out a legionella risk assessment to identify any risks and set out ways in which the risks can be reduced.
2. Completing any remedial works identified during the risk assessment, such as water tank cleaning or plumbing alterations, to ensure all water systems meet the current standards.
3. Carrying out regular ongoing monitoring to ensure the risk from legionella bacteria is managed and that control measures are working effectively.

Managing risk, minimising disruption

Caravan and holiday parks share several unique factors that require special consideration. These include; fluctuation in demand for water, seasonality, large volumes of stored water, tank-fed drinking water and the management of spa and swimming pool complexes. Typical maintenance work that should be scheduled includes:

• Legionella risk assessment
• Cold water storage tank cleaning and disinfection
• Showerhead descaling and disinfection
• Pipework alterations
• Descaling of water cylinders and calorifiers (quarterly)
• BS8558 flushing and disinfection on new buildings
• Drinking water sampling

Disruption to guests (and to the business) can be minimised by adopting a proactive approach and spreading maintenance work throughout the year, with the most invasive and disruptive tasks being carried out in the off season. In fact, several tasks are best carried out before the season gets under way, such as the cleaning and disinfection of cold water storage tanks, the flushing out of little used outlets and the descaling and disinfection of showerheads.

Work to be carried out, out of season

Cold water storage tank cleaning and disinfection 

Caravan and holiday parks often have a large cold-water storage tank, possibly located outdoors or underground, that feeds all services. These tanks must be inspected annually to check their condition and whether cleaning is required. To comply with water regulations tanks must have the following:

• A close-fitting lid made of a suitable material in good condition.
• Insulation to control temperature.
• Vermin and insect screens.
• Opposing inlet and outlets.
• Overflows, vents and warning pipes in good condition.

Stagnation is a common problem with over-sized tanks or where water usage fluctuates throughout the year. Stagnant water creates a habitat in which legionella bacteria can grow and multiply to sufficient numbers for an outbreak to occur. Therefore, it is imperative to avoid stagnation by the regular flushing of little used outlets, and the cleaning and disinfection of the storage tank.

Reduction of water storage

Electronic tank level switches can be installed to control the capacity of stored water in off-peak or low season to match reduction in demand. Reducing the amount of stored water will reduce the possibility of stagnation and help maintain healthy functionality.

Showerhead descaling and disinfection

Legionnaires’ disease is normally contracted by inhaling tiny, airborne droplets (aerosol) of legionella bacteria. Showers are a notorious source of aerosol, therefore the hose, inserts and showerheads must be dismantled, cleaned, descaled and disinfected on a quarterly basis.

Descaling water cylinders and calorifiers

The build-up of limescale within a hot water cylinder or calorifier is a common cause of systems not working efficiently. It can result in both a reduction of water flow and poor temperature control. Chemical cleaning can remove limescale which both reduces the risk of legionella and improves energy efficiency, so reducing heating costs.

Refurbishment and new buildings

If any new building work, extensions or alterations are carried out on a caravan or holiday park site, new water systems must be flushed and disinfected to comply with British Standard 8558 and current water regulations. This ensures they are hygienic and ready to be put into service. A certificate must be provided to prove the work has been carried out.

On-going maintenance to be done during holiday season

The simplest and most common method of controlling legionella in hot and cold-water systems is by controlling the temperature. Hot water needs to be stored at 60°C in cylinders or calorifiers and must achieve 50°C at all outlets within 1 minute of running the tap. Cold water must be stored at below 20°C and not exceed 20°C within 2 minutes of running the tap. Monthly monitoring of temperatures must be carried out and recorded, and if these control temperatures are not being achieved further control measures will need to be implemented. Infrequently used outlets must also be flushed through on a weekly basis to reduce the risk of stagnation and ensure temperature control is maintained. Showerheads must also be checked on a quarterly basis.

Drinking water sampling

Drinking water supplied from cold-water storage tanks must be routinely tested to ensure the water is safe to drink.

Professional guidance ensures peace of mind

With so much else to think about, it’s not surprising that many caravan and holiday park managers choose to appoint a specialist to help ensure they are fully compliant with current HSE guidance. Dantek Environmental Services specialise in water hygiene and can help solve any problem that water might cause in the built environment. Their highly trained and experienced team provide expert technical advice and support to ensure compliance is achieved and provide peace of mind. Managing Director of Dantek, Dan Collins said, “We advise on all matters concerning water and the built environment and can work with caravan and holiday park owners to help prevent Legionnaires’ disease. Our advice helps ensure best practice and provides peace of mind. With new customers, I feel it works best if we meet on site to really get a good understanding of their concerns and identify where we can add value. To do this we offer a free initial legionella consultation which is generally a good place to start.”

For information contact Dantek on 01454 417920 or visit http://www.dantekenvironmental.co.uk/water-hygiene-legionella-risk-assessment

For information on Legionnaires’ disease visit  http://www.hse.gov.uk/legionnaires/