Hard Water and Legionella: An Underestimated Problem
Hard Water and Legionella
The connection between hard water and Legionella is well known, but often misunderstood. In this article, we will explore how to gain better control over the bacterial content in water from the start, in order to reduce the use of aggressive and environmentally harmful chemicals.
Control of Bacterial Content in Water
Chlorine dioxide remains the most commonly used biocide for eliminating bacteria in water, including Legionella. Its ability to destroy biofilms is a significant advantage. However, chlorine dioxide is only for control and reduction, not prevention. The key lies in understanding the connection between limescale, biofilms, and Legionella. This can help reduce the number of bacteria in your water system and minimize the effort and chemical consumption for maintenance.
What is Limescale?
Limescale mainly consists of calcium carbonate (CaCO3) and accumulates in hot water systems, pipes, and appliances. It can significantly impair the performance of sanitary and heating components, leading to reduced efficiency and higher operating costs. Water hardness determines the degree of limescale formation:
- Soft Water: 0 to 7 degrees German hardness (dH), hardness range I (0 to 1.3 millimoles of calcium oxide per liter).
- Hard Water: 14 to 21 degrees German hardness (dH), hardness range III (2.5 to 3.8 millimoles of calcium oxide per liter).
What is a Biofilm?
A biofilm consists of microorganisms, such as bacteria, that settle and multiply in a community. These microorganisms adhere to surfaces in a moist environment and secrete a sticky substance.
What are Legionella?
Legionella are bacteria that can cause Legionnaires' disease, a severe form of pneumonia. Transmission occurs through inhaling tiny water droplets that contain Legionella. There are 48 species and 70 subgroups of Legionella. They are commonly found in hot water systems, but their prevalence is decreasing thanks to better sanitary measures.
Optimal Conditions for Legionella:
- Freshwater Replenishment
- Long Retention Time
- Temperature Range 25 °C to 50 °C
Temperature Ranges and Legionella:
- up to 20 °C: Very slow reproduction
- 20 °C to 45 °C: Optimal reproduction, doubling at 36 °C in about 3 hours
- from 50 °C: Little to no reproduction
- from 55 °C: No reproduction possible, death after 6 hours
- from 60 °C: Death within about 30 minutes
- from 65 °C: Death within 2 minutes
- from 70 °C: Death within seconds
(Source: Wikipedia)
Connection Between Limescale, Biofilm, and Legionella
Limescale, which forms from minerals in hard water, provides an optimal breeding ground for bacteria. Legionella thrive at temperatures between 20 and 45 °C and multiply rapidly when water remains in this range. The limescale provides an excellent food source, allowing bacteria to multiply easily and form a biofilm. In the presence of limescale and biofilm, Legionella find ideal conditions to reproduce and thrive.
Solution: PureStream Products
This is where PureStream comes in. Our filtration technology helps reduce limescale and bacterial growth, improving water quality and minimizing the risk of Legionella. Ideal for use in hotels, gyms, homes, nursing homes, and hospitals.
Use PureStream products for a hygienically perfect shower experience and enjoy clean, chemical-free water.
