UK National Reference Laboratory for food microbiology

Guidance and responsibilities of the UK's National Reference Laboratory (NRL) for food microbiology.

The UK’s NRL for food microbiology is responsible for official controls on specific areas of food microbiology:

  • Listeria monocytogenes
  • coagulase positive staphylococci
  • Escherichia coli (including STEC)
  • campylobacter
  • salmonella
  • antimicrobial resistance

The Food Standards Agency (FSA) awarded the UK Health Security Agency (UKHSA) these responsibilities for performing official controls to ensure the verification of compliance with feed and food law, animal health and animal welfare rules. This is described in Article 101 of Regulation (EU) No 2017/625, which is now the retained EU legislation (REUL) in the UK, UK Statutory Instrument 2019 No. 665.

When implementing and using ISO Standards, there is some supporting information to help food laboratories, including news and method validation and verification presentations.

Expert witness information

Local authorities and port health authorities ask staff in official laboratories (OLs) to provide witness of fact statements, advice to prepare material for prosecutions, and requests for suitable expert witnesses. The UK NRL can provide advice and practical support.


National Reference Laboratory

Food, Water and Environmental Microbiology Services
UK Health Security Agency
61 Colindale Avenue


Telephone 020 8327 7160 / 7325

Standard methods and public health guidance

Below is a list of procedures for the laboratory examination of all food types and environmental samples that the NRL can provide to other laboratories. Please contact us using the details above to request the procedures and this will ensure the most current version is made available.

The standard methods and public health guidance available include:

  • determination of pH in food and water samples (FNES63.04)
  • determination of water activity in food (FNES67.04)
  • enumeration of coagulase-positive staphylococci (Staphylococcus aureus and other species) (FNES8.07)
  • preparation of samples and dilutions, plating and sub-culture (FNES26.05)
  • enumeration of β-glucuronidase positive E.coli: pour plate method (FNES3.07)
  • detection and enumeration of Listeria monocytogenes and other Listeria species (FNES22.06)
  • enumeration of β-glucuronidase positive E.coli: most probable number technique (FNES131.01)
  • detection of Salmonella species (FNES16.08)
  • detection and enumeration of Campylobacter species (FNES15.07)
  • detection and enumeration of bacteria in swabs and other environmental samples (FNES4.06)
  • guidance on public health response: involvement of UKHSA Food Water and Environmental Microbiology Laboratory staff in the investigation of outbreaks of food or waterborne disease (FNES18.04)
  • verification and validation of methods (FNES61.01)
  • measurement uncertainty in testing (FNES66.03)
  • detection and isolation of shiga toxin-producing Escherichia coli (FNES144.03)
  • preparation of positive control DNA for use in real-time PCR assays for foodborne pathogens (FNES45.04)

Reports and audits

National reference laboratory for food microbiology: annual report

Audit of official laboratories (OLs)


Previous NRL guidance can be found on the National Archives website.


Updates to this page

Published 22 November 2023
Last updated 7 February 2024 + show all updates
  1. Added document and version numbers to methods.

  2. Added 2 procedures to Standard methods and public health guidance section.

  3. First published.

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