Water Sampling and Analysis

There is a perception that people have to take water samples and check for legionella bacteria. This is NOT necessarily the case. Microbiological monitoring is a method of monitoring the levels of microbiological activity in a sample of water. Routine monitoring of "domestic" water systems is NOT necessary. It is known that legionella (and other bacteria) occur at low levels in perfectly fit to drink mains supplied water and experience shows that legionella bacteria are present in about 13% of water samples i.e. 1 in 7. Problems occur when the bacteria are allowed to multiply.

Legionella samples need only be taken where it is deemed appropriate e.g. where low temperatures (in hot water systems) are set due to using biocides or in ‘at risk’ hospital wards OR where the client requests or specifies that is what they want.

Clients may have concerns regarding general water quality which may call for a sampling programme to be put in place.

Our approach is to help you comply with the law, reduce the risks from legionella bacteria and other organisms and do so cost effectively. So we’ll advise you where to save your money and legionella testing is one such area. So spending time and money on samples may be missing the point. The key is to implement adequate control measures and a written scheme for reducing the risk.

Steve Mount Associates Ltd. can advise on whether your water systems need sampling and if so, set up a structured monitoring regime covering Legionella or indicator organisms which will be cost effective, allowing us to interpret the results and act upon them if required. The interpretation of results is carried out by Steve Mount BSc (hons) CBiol MIBiol MWMSoc an experienced microbiologist.


Sampling for Legionella is carried out in accordance with BS 7592:2008 Sampling for Legionella bacteria in water systems – Code of practice.

Indicator organisms

Sampling for general indicator organisms such as:
  • Colony count bacteria (TVC)
  • Coliforms
  • E.coli
  • Pseudomonas aeruginosa
  • Clostridium perfringens
are carried out using methods laid down in The Microbiology of Drinking Water 2010-Part 2-Practices and procedures for sampling.

Analysis of water samples for legionella and Indicator organisms are carried out by a UKAS accredited laboratory which takes part in the Health Protection Agency (HPA) Water Microbiology External Quality Assessment Scheme for the Isolation of Legionella from Water and the EQUAL Scheme for Indicator Organisms.

For more information on our Sampling and Analysis services please complete the
contact form, call us on 0778 752 4066 or email stphmount@yahoo.co.uk