UKAS-accredited Total Viable Counts (TVC) testing for water systems

Laboratories of Eurofins Water Hygiene Testing provide UKAS No. 9658, 9508 and 1369 accredited Total Viable Counts (also referred to as Heterotrophic Plates Counts; HPCs) testing for water systems. Our services support duty-holders in commercial, healthcare and industrial settings to monitor microbial loads, detect system deterioration and maintain water hygiene programmes.

What is a Total Viable Count?

A Total Viable Count (TVC) is a non-selective microbiological test that estimates the number of live microorganisms, such as bacteria, yeasts and moulds, in a water sample. The test does not target specific pathogens, or indicate faecal contamination, it provides a broad indication of a system’s general microbiological condition.

Why test TVC in water systems?

TVC testing plays a key role in water hygiene programmes because:

  • Elevated counts can indicate biofilm growth, stagnation or poor disinfection
  • It helps establish a baseline and trend for microbial activity; significant increases often trigger further investigations
  • It applies across multiple sectors, drinking water, process and manufacturing water, and healthcare end-use outlet testing, as a first-line indicator of system hygiene

While there are no strict regulatory limits for TVC in most UK water systems, guidance such as that from the Drinking Water Inspectorate (DWI) suggests no significant increase from mains supply values.

Accredited laboratory methods

Eurofins water hygiene testing has UKAS-accredited laboratories provide TVC testing using recognised culture-based methods. Typical methodologies include membrane filtration onto general nutrient agar or yeast-extract media, with incubation at 22 °C and/or 37 °C or 30 °C, depending on the application and regulatory requirement.

Results are expressed in colony forming units (cfu) per mL or per 100 mL depending on matrix and are typically available within 48 to 72 hours. Interpretation focuses on trend and change rather than absolute values.

Recommended sectors and sample types

Our TVC testing is suited for:

  • Drinking and potable water supplies in commercial buildings and private systems
  • Endoscope washer-disinfector and healthcare rinse waters
  • Cooling towers, industrial process loops and closed loop systems
  • Hot and cold-water services in leisure and hospitality
  • Surface and environmental waters where microbial hygiene is a concern

By integrating TVC with targeted tests (e.g., Pseudomonas aeruginosa, Legionella pneumophila), you strengthen your water-hygiene monitoring strategy.

Why choose Eurofins Water Hygiene Testing

  • UKAS-accredited microbiology testing covering TVC and a full suite of water hygiene determinands
  • Supports commissioning, maintenance, and routine hygiene assessments.
  • Consistent turnaround times to support project timelines and reactive requirements.
  • Nationwide logistics and sample drop-off network for fast, reliable service
  • Trusted by healthcare estates, building services, water treatment professionals and regulatory consultants

UK-wide drop-off facilities

Eurofins UK clients benefit from our extensive and free to use logistics and sample drop-off network with over 60 drop-off locations.

Sample bottles

To ensure that we are able to test your water chemistry samples please submit them in appropriate sample bottles. 

Get in touch

Would you like to find out more about our water hygiene testing and compliance services? Contact Eurofins Water Hygiene Testing UK today by submitting an enquiry form or calling +44 (0) 845 604 6740.

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