Monitoring Your Building Hot & Cold Water Systems for Legionella
Sat 15th August 2020
Article · Sat 15th August 2020

Monitoring Your Building Hot & Cold Water Systems for Legionella

The risk of exposure to legionella must regularly be controlled by measures that do not permit the development of legionella bacteria in water supplies which include the avoidance of water temperatures among 20 C and 45 C, which leads to the development of legionella bacteria and other organisms.

Here are the standards for hot & cold water temperature:

Cold Water

After running the cold water for up to two minutes, the cold water temperature of your systems should be below 20 degrees Celsius and must be tested and formally tracked on a monthly basis.

Hot Water

The temperature of the hot water should be at least 50 degrees Celsius within one minute of running the hot water (55 C in the health sector) and must be tested and formally tracked on a monthly basis.

Testing and logging the hot and cold water systems frequently is an essential task if you want to prove compliance with the law.

There are several solutions on the market right now, including:

  • Legionella thermometer
  • Legionella testing kits
  • Legionella sensors (water temperature sensors)

1. Legionella thermometers

Thermometers are an easy way to help landlords or any other responsible person to measure temperatures in their sites. When purchasing a thermometer you need to keep in mind that not every thermometer can measure both °C and °F, record data for legal purposes, and even provide accurate readings.

2. Legionella testing kits

Testing kits are a simple way to monitor the legionella pneumophila presence in water systems with a turnaround of 25 minutes to 48 hours. Testing kits come with clear instructions and do not require any additional training for their use.

3. Water temperature sensors

Water temperature sensors are the most advanced and cost-effective way to monitor the temperature of any water system with accurate live readings and logging within our L8log ecosystem. The water temperature sensor has a transmitting range of 22 KM and has an astonishing battery that can last up to 10 years

It is also recommended to conduct a legionella risk assessment at least once every two years where trained professionals perform several checks in order to assure your water system is safe to use.


Florin Mangu