Disinfection

We can provide a full range of services for cleaning and disinfection of cold water storage cisterns, hot & cold above ground pipework and below ground water mains.

• Our disinfection procedures comply with BS6700, the Water Supply (Water Fittings) Regulations 1999 and Water Company requirements.
• Design and planning services, including approval application if required.
• All disinfection work is undertaken by appropriately qualified and experienced personnel. 
• We take full regard of the environmental impact and health & safety requirements to all persons in the immediate site vicinity and can provide method statements and risk assessments for any specific project. 
• WSM Associates carries all necessary insurance cover, including professional indemnity.  Details can be provided on request.
• All our works can be undertaken at a time and day to suit your requirements.
• For underground pipes over 50mm diameter and most new internal water systems and a bacteriological water quality certificate will be required by the local water company, prior to making a new water connection to their distribution system.

Equipment and chemicals

Mobile dosing equipment is used for disinfection of all underground pipework and internal pipework systems.  These units are fully maintained, calibrated and certificated to ensure accurate operation.  These units also provide a “no flow” fail safe facility to prevent over dosing.
We also manufacture a range of standard chlorination dosing units (link).  We can also design and manufacture to clients’ specification as well as offering the above mentioned servicing, calibration and certification.
Disinfection is generally carried out using sodium hypochlorite, with sodium thiosulphate used to neutralize the solution.  Storage and usage complies with COSHH regulations.

Underground Pipework

The disinfection of underground mains and pipework normally follows a five stage process:

1. Swabbing – WSM can provide a full swabbing procedure to complete a physical cleaning of any main, using specifically a designed test assembly procedure.

2. Chlorination – Using one of our dosing units suitable to the size of the main required we can accurately inject our disinfectant chemical (sodium hypochlorite) to any concentration as required by a client (usually 30 part per million to conform with industry standards) through the entire length of a main.

3. Dechlorination – After injection of the disinfection chemical and an allotted standing time this chemical must then be removed and neutralized back to safe levels so as not to cause harm to the surrounding environment.

4. Water quality sampling and UKAS laboratory analysis to ensure satisfactory disinfection, find more details under water quality (link).

5. Final certification for proof to the local water company for permission to connect onto their distribution system.

Cold Water Storage Cisterns

We provide a complete service for water cisterns, large or small, from an initial inspection through to final water quality certification. This can include a physical cleaning process, involving removal of sediment and other build ups from the walls and floor of a cistern, as well as a chemical disinfection to remove any bacteriological presence.

Aboveground Pipework

In addition to cleaning and disinfection of cisterns we can also provide disinfection of down services, improvements to comply with the Water Supply (Water Fittings) Regulations 1999, such as insulation, pipework alterations and cistern replacements.        

Example of Certificate