Water PT scheme sample instruction sheet

Legionella Isolation

The final date for return of results is indicated on the accompanying request/report form

Contact details:
The Organisers - FEPTU
UK Health Security Agency
61 Colindale Avenue,
London, NW9 5EQ, UK.
Tel: +44 (0) 20 8327 7119
e-mail: foodeqa@ukhsa.gov.uk
Results should be returned on-line using the web-based reporting system. Go to: www.phe-eqa.org.uk. You will need your log-in details for this process. Please contact us if you experience problems with the on-line system.

Legionella Isolation

Scheme – Instruction Sheet

Each distribution consists of two LENTICULE® discs in screw-cap plastic vials (with desiccant). The LENTICULE discs require reconstitution by a process of re-hydration and
dispersion prior to examination for legionellae.

Refer also to the Safety Data Sheet: Safety data sheet - LENTICULE

For a video on sample processing: Processing samples - Legionella Isolation Scheme

Storage:

  • Store the samples at –20 ± 5ºC on receipt.
  • Allow the LENTICULE discs to reach ambient temperature (5 - 10 minutes) before reconstituting in diluent.

Reconstitution:

  • Open the sample container and transfer the LENTICULE disc into 1 Litre of diluent (use either Page’s saline or 1:40 Ringers’ solution) by inverting the container over the diluent.
  • Leave at ambient temperature for a minimum of 10 minutes to rehydrate. Ensure that the LENTICULE disc has dissolved completely before proceeding.
  • Disperse the inoculum by inverting approximately 30 times.
  • Examine samples between 30 - 45 minutes after reconstitution.

Examination:

  • Each reconstituted LENTICULE disc is equivalent to a 1 Litre water sample.
  • The request/report form indicates the sample dilutions most likely to give a definitive result (rather than a censored value).
  • Once the dilutions have been prepared, the samples must be examined in accordance with routine procedures.
  • All samples require examination for the presence of Legionella spp.
  • The identification and level (colony forming units per Litre (cfu L-1) of any legionellae detected must be determined.

Return of Results:

  • Return your results on-line using the web-based reporting system.
  • The distribution will be closed on the deadline date for return of results.
  • Results cannot be accepted after the distribution has closed.