Business owners in the Netherlands must be aware of the dangers of Legionella and prevent its growth to dangerous levels. Legionella is the name of a bacteria that can cause an infection of the airways called legionellosis, or Legionnaire’s disease. The bacteria may grow in warm water such as tap water, swimming pool, hot tub and bath water, fountains and sprinkler water at garden centres and (car) washing machines or cooling water in wet cooling towers. Building owners are responsible for the quality of tap water. They must ensure that the health of people in contact with this water is not at risk. Practical measures for complying with this duty of care can be found at Zorgplicht-legionella.nl (in Dutch).
Some businesses and institutions are subject to stricter regulations on primary legionellosis prevention. If you own a hotel, public swimming pool, campground or marina, for example, you must engage a certified company to conduct a risk analysis and draw up a Legionella management plan of your water supply system. This plan describes the periodical preventive checks and the maintenance of your water supply system. You must check the water, or have it checked, at least twice a year. If the standard of 1,000 colony-forming units per litre is exceeded, you must report this within 48 hours to the Human Environment and Transport Inspectorate (Inspectie Leefomgeving en Transport, ILT) (in Dutch).