- All Cold Water Tanks should be emptied, scrubbed, and their walls whitewashed with chlorinated water.
- All Hot Water Tanks (boilers) should have their interiors (inner surfaces) cleaned (removal of lime scale and sediment).
- All Filters connected to the water system should be removed for detailed cleaning and disinfection.
- All Shower Heads, shower hoses, faucet aerators, and garden irrigation sprinklers should be removed for detailed cleaning and disinfection.
- All Cooling Towers should undergo detailed cleaning and disinfection.
- All pool Balance Tanks and Filter Sands should be thoroughly cleaned and disinfected.
- Perform Chlorine Shock Treatment by adding chlorine to cold water tanks. The target free chlorine concentration is 3 ppm, with a 24-hour retention time inside the system.
- Perform Thermal Shock Treatment by raising the water temperature inside boilers to 70 ºC and running hot water from all showers and faucets (bath, hairdresser, etc.) at a pencil-thickness flow for 5 minutes each.
- Raise the water temperature inside boilers to 70 ºC and measure and record the temperature at the bottom drain valve.
Record Keeping
Document all performed procedures on appropriate forms or minutes, and sign them.
Important
To reduce the risk of Legionnaires' disease, be sure to perform the above-mentioned procedures before the season starts.
Note: The required actions may be more than those listed above. The important ones are indicated as reminders, and the priority may vary depending on the risk conditions.
Number: 24 • March 14, 2013