Mains Water Chlorination to BS8558
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Mains Water Chlorination to BS8558

Mains Water chlorination to BS8558


Comfort Services Group is a leading independent UK water treatment and water hygiene company offering expert water management. Contact us today to learn how our water management and engineering solutions can help you.

Why choose Comfort Services Group?
  • Our practices conform to the British Standard BS8558 and we are members of the Legionella Control Association
  • All our services are managed under our quality standard ISO 9001:2015 and we are a member of BSRIA to ensure we maintain a high standard of service when on the site. We are also accredited by SAFEContractor, Constructionline and all our engineers are CSCS card holders. This is in addition to a wealth of experience working on construction sites.
  • We have dedicated vehicles, equipment and dosing systems
Why choose Comfort Services Group?
New mains chlorination

In order to safeguard water quality and public health, the water supply pipes have to be chlorinated and tested before a connection is allowed to the water main. 

Comfort Services Group is a specialist water treatment & testing provider on the water supply networks that include Anglian Water, Thames Water, Affinity Water, Essex & Suffolk Water and other water boards should the need arise.

New mains chlorination is important in order to maintain quality of the mains drinking water supply. Water board companies, like above mentioned Anglian Water, will not allow the connection of new mains pipe onto their system until the new pipe work has been chlorinated effectively and a detailed and comprehensive chlorination certificate and microbiological analysis have been provided.

We can provide a full chlorination and testing service for all new mains connections, whether the system is a large commercial building, or smaller domestic pipework.

New mains chlorination
External / New mains Water Supply Chlorination

When new water mains supply are installed to a site, there is a mandatory requirement by the local water authority for the pipework to be flushed and disinfected in accordance with their specifications. Under the Water Supply Regulations 1999 (SI 1999, 1148) all new or modified water systems require this treatment to be performed before they can be connected to the mains supply to prevent contamination of the water supply. The disinfection must be carried out to ‘BS8558’ standards. This is to ensure there is no detriment to public health.

New supplies should be:

• Flushed and where possible swabbed to remove any contamination that has been introduced during installation.

• The water mains will then be filled with a disinfecting solution for at least an hour, ensuring that the strength is maintained throughout the disinfection process.

• After the disinfection period the water mains must be flushed with good quality potable water, until the chlorine residual measurements show that the chlorine concentration of the water leaving the mains is no higher than that generally prevailing in the distribution system.

• To confirm the efficacy of the disinfection process water samples are taken from the furthest outlets on the system; these are then sent for testing for TVC, E-coli/ coliforms, Pseudomonas and Legionella by a UKAS accredited laboratory.

• The water mains must be left in a sealed state to ensure the sterile condition.

Upon completion the client is issued with a disinfection certificate clearly stating that the works have been carried out to BS8558, appropriate for any water authority, as well as subsequent microbiological sample analysis results from a UKAS accredited laboratory.

Requirements for chlorination and specific tests needed may vary depending on the water utility company (e.g. Anglian Water, Thames Water etc.). It is recommended to check with the specific utility company what is required and the level of certification expected before the chlorination goes ahead.

External / New mains Water Supply Chlorination