Legionella bacteria are common and can be found naturally in environmental water sources such as rivers, lakes and reservoirs, usually in low and not dangerous numbers. Water temperatures between 20 and 45 degrees Celsius, the present of biofilm and stagned water are the ideal circumstances for the growth of the Legionella bacterium.

It is only contracted by inhaling Legionella bacteria in tiny droplets of water (aerosols) deep into the lungs. Aerosols are small water droplets released by spraying, such as showers, fountains, humidifiers, air-conditioning systems, whirpools and cooling towers. Person-to-person spread of the disease has not been documented.

The unique PB International self-cleaning Legionella filters remove mechanically the Legionella bacteria, without chemicals. The PB-filter elements gives the best possible protection against infection from the Legionella bacteria.