
Hotel and Resort owners need to be aware of the risk of legionella in their water supply and how its presence can affect their guests.
Businesses in the hospitality and leisure industry are at a greater risk of being impacted by legionella and legionnaires’ disease due to these supplies being consumed and enjoyed.
Business premises using their water supplies for guest consumption or enjoyment such as swimming pools, spas and hotel rooms need to ensure they have a secure legionella risk assessment process in place to prevent guests contracting legionnaire’s disease.
What is Legionella?
Legionella bacteria naturally occur in Scotland’s water sources such as rivers, lochs, and reservoirs. These bacteria can infiltrate manmade water systems and breed in your water tank. This is when Legionella becomes hazardous to human life.
Temperature is the most important factor concerning the spread of legionella:
Below 20°C – Legionella bacteria is dormant
Above 60°C – Legionella bacteria cannot survive
Between 20°C and 45°C – Legionella bacteria breeds rapidly
Legionella is commonly transmitted by inhaling contaminated water droplets. Air conditioning cooling towers, hot and cold-water systems, humidifiers, showers and whirlpool spas are common culprits for harbouring legionella.
When you inhale contaminated droplets, you’re at risk of catching Legionnaires’ disease.
What is Legionnaires’ Disease?
Legionnaire’s disease is a potentially fatal pneumonia. It’s frequently misdiagnosed because early symptoms resemble the flu or a cold. Legionnaires’ disease is fatal in around 10% of cases.
Groups at particular risk of Legionnaire’s disease are:
- People over 45 years old
- Those with chronic respiratory or kidney disease
- Heavy smokers and drinkers
- People with lung disease, heart disease and diabetes
- Individuals with compromised immune systems
A Legionnaire’s Risk Assessment carried out by competent professionals is the best way to protect against Legionnaires’ disease.
Hotels and Resorts with Legionella Outbreaks

Hotels and Resorts often house many guests at any one period. Most of these guests will use showers or baths, drink the water from the pipes and use leisure facilities, which all are fed from one water supply.
If a legionella outbreak was to occur in a hospitality premises, the number of guests affected is far larger than those of a private residence.
Hotels with swimming pools, hot tubs and jacuzzi are at a particularly higher risk as legionella bacteria stands the best chance of thriving when the water temperature is between 20 and 45 degrees celsius.
The high humidity and formation of water aerosols that may be present will also increase the odds of someone breathing in contaminated water droplets if legionella is present.
Those responsible for your business water supply should be aware of the most up to date legionella control guidance and should ensure a legionella risk assessment is conducted regularly.
Should a guest contract Legionnaires’ Disease from your premises they can become incredibly unwell and, in some cases, may even pass away. These claims are particularly costly for businesses, both financially and through damage to the business reputation.
Legionella in Care Homes or Nurseries

Legionnaires’ Disease can prove to be particularly fatal if found in premises housing vulnerable groups such as elderly people, young children or those that are otherwise compromised.
As the water is being regularly consumed and utilised by those in the residence is it important that an effective legionella control process is in place.
A sufficient legionella control program would include the following:
- An up-to-date legionella risk assessment
- A written scheme of control in place
- A schematic diagram of the hot and cold-water system
- Records of all necessary checks, tests, and inspections
What should be included in a Legionella Risk Assessment?
A Legionella Risk Assessment should combine both a physical inspection and a consultation with those involved in controlling the bacteria in the premises, including the verification of management procedures and paperwork.
Previous LRA’s will be consulted to ensure any remedial works or risks identified previously have been carried out.
The site will then be toured, checking where water is stored or where there is the potential for aerosols to be created.
The following points will then be identified:
- Are there any high-risk groups present in the building, such as elderly people or vulnerable people due to illness?
- Descriptions of both cold and hot water systems, where the supply is fed from, what the storage process is, etc
- Recording water outlet temperatures to ensure they are out with the optimum legionella temperatures.
- Are the water tanks accessible, insulated, tightly covered to prevent vermin or foreign matter entering
- What systems are being used for hot water systems? Are these adequately insulated?
- Noting any other additional areas of risk, such as shower valves being well maintained, any redundant pipework that needs to be removed, if there are any areas of the property left regularly unattended, etc?
What should be included in a Written Scheme of Control (WSOC)?
A WSOC details who is responsible for the water supply and what measures are being taken to prevent bacteria outbreaks, and ensure any water is safe for consumption and use.
Information that should be detailed includes:
- Inspection and chlorination of hot and cold-water tanks annually or as per their most recent risk assessment
- Annual servicing and cleaning of TMV’s (Thermostatic Mixing Valves)
- Quarterly descaling and disinfection of shower heads, hoses, and taps
- Monthly temperature checks at the sentinel taps
- The routine flushing of unoccupied rooms of infrequently used outlets.
The responsible person must also ensure that any recommendations listed in their legionella risk assessment are carried out and signed off when completed, as evidence of this might be requested during an inspection.
Preventing Legionella in High-Risk Environments

There are a number or preventative measures you can take to ensure legionella does not become a problem in your premises.
- Ensure you are having regular Legionella Risk Assessments carried out by an authorised professional such as PHX Water
- Keep your water tanks clean and regularly disinfected to minimise the chance of bacteria growing
- Ensure water tanks are kept are temperatures where legionella cannot thrive (between 20 and 45 degrees celcius). The optimum temperature for hot-water tanks is between 60 and 65 degrees celcius and cold-water tanks is between 15 and 24 degrees.
- Protect your business by ensuring your public liability insurance covers you for legionella outbreaks.