Water filters that are installed at the kitchen faucet, also called point-of-use (POU) filters, can be useful when patients with weak immune systems are in need of additional layers of protection. These filters can be installed at the point where water comes out of the tap. It is very important that these filters be changed according to the manufacturer’s recommendations because if not, Legionella bacteria can grow on the filters and actually lower the water quality. Various filters are commercially available and can be found through search engines using the search terms "Legionella Water Filter".
Commercially available filters should always be changed according to the manufacturer’s instructions, and include the following types:
- Showerhead and Faucet filters
- Refrigerator and icemaker filters
- Whole house water filters
Humidifiers create fine mists of water that can host and transport Legionella bacteria straight into your lungs, if they are not cleaned properly.Humidifiers can be complex appliances, so it is best to follow the manufacturer or the supplier’s instructions for cleaning and maintaining them. Various types of humidifiers may present different levels of risk for exposure to Legionella bacteria.
In order of riskiest to least risky, the different types of humidifiers are:
- Atomizing humidifiers: also called cool air humidifiers, use mechanical action air to create a water mist that evaporates into the air stream. These units require regular cleaning.
- Heated pan humidifiers: use a heat source to evaporate water from a pan open to the air, but do not create water mists. The "on-use" of the device as well as the with a warm pan of water can create a home for bacteria to grow.
- Direct steam-type humidifiers: these inject boiler-generated steam directly into the air. These systems do not create water mists and normally operate above 158°F, a temperature at which Legionella bacteria cannot survive.
Regularly cleaning your humidifier by following the manufacturer’s instructions will ensure it remains free of bacteria.
Evaporative Cooling Fans
No cases of Legionnaires disease have been associated with evaporative cooling fans, and the risk is thought to be low because no aerosols are produced and cold water is used. Regular maintenance is recommended to reduce the accumulation of slime and scaling and minimize any potential Legionella risk, which includes removal of any scale, periodic cleaning of the wetted surface, and draining before storage or when not used.