Menu
Log in
Intranet

Tank Cleaning and Disinfection

When do potable water tanks need to be cleaned?

Potable water tank
When do you need to clean a drinking water tank?

Drinking water or potable water tanks must be kept in good condition, be correctly installed and designed to ensure the water quality is maintained, and is fit for human consumption.

If you rely on tank fed water for your drinking water, then it should meet the following requirements:

  • Correctly sized so stagnation does not occur, and fresh water is replenished frequently.
  • Constructed of a WRAS approved material e.g. plastic (polyethylene) and have a close-fitting lid.
  • Has a lid which excludes light and is tightly fitted and securely fastened to prevent birds, rodents and dust from getting into the tank.
  • Has a lid vent and overflow with a screen to prevent dust, insects, birds and vermin getting into the tank.
  • The tank must be insulated to keep temperature below 20 degrees.
  • Inspected visually at least annually to make sure there has not been a build up of scale or sludge and the lid and screens are all securely in place.
  • Cleaned and disinfected annually or sooner if microbiological monitoring indicates deterioration or if visual inspection shows sludge, scale or corrosion.
  • Microbiological samples should be taken at intervals of not more than 6 months if there is a change in water quality, the tank is not adequately protected, it leaks or is corroding.

 

Dantek can offer advice to correctly identify potable water tanks and then monitor those tanks to ensure the water quality remains fit for human consumption. For a free consultation about your cold-water storage tanks please call 01454 417920 today.

How often do cold water storage tanks need to be cleaned and disinfected?

Tank Cleaning & Disinfection

Cold water storage tanks should be kept clean and free from nutrients, including corrosion, scale and biofilm (HSG274 part 2).  However there is in fact no definitive recommended timeframe for cleaning tanks, so they must be cleaned as necessary or if any of the following occur: 

 

  •  Installation of new water system or refurbishment of hot and cold-water system
  • Installation of new components to the water system 
  • When the hot and cold-water system has not been used for long periods and has not been flushed 
  • When routine inspection of the tanks deems it necessary because there is visible evidence of contamination or stagnation 
  • If the system has been significantly altered or entered for maintenance purposes 
  • If water samples taken from the system show there is evidence of microbial contamination 
  • During or following an outbreak of legionnaires’ disease associated with the system 
  • When a risk assessment has indicated a tank clean is necessary 

 Clean cold water storage tank

A chemical disinfection will typically be chlorine or hydrogen peroxide dosed to achieve the required ppm and maintained for at least an hour throughout the water system. The chemical is pulled through to all outlets and tested to ensure the entire system is treated effectively. 

After the and before the system is put back in use the disinfectant must be flushed from the system if using chlorine, or if using hydrogen peroxide be below the maximum level for potable water. 

Dantek have a team of highly trained technicians who carryout this type of work regularly. We are experienced in cleaning all sizes of tanks from small 50-gallon tanks in nursing homes to very large industrial size and everything in between. 

To get a quote for tank cleaning and disinfection please contact our sales team who will be able to advise what to do at your site. 01454 417920  sales@dantek.co.uk 

 

Back To Top