Conduct shellfish depuration operations

Business Sectors (Suites): Fish and Shellfish Processing
Developed by: Improve
Approved on: 01 Jan 2019


This standard is about the skills and knowledge needed for shellfish depuration in the shellfish processing sector. It details the skills required to prepare for and complete shellfish depuration.

You must know and understand how to work to organisational product specifications and production schedules.

This standard is for you if you are involved in the processing of fish and shellfish and deal with the depuration of shellfish.

Performance criteria

You must be able to:

  1. conduct shellfish depuration operations in accordance with organisational standards
  2. obtain tools and equipment required to support planned operations, including hygiene and personal protective equipment
  3. prepare depuration system ensuring a hygienic working condition suitable for receiving shellfish is maintained
  4. receive shellfish and confirm they are suitable for depuration
  5. prepare shellfish for depuration by grading, washing and removing dead and damaged animals
  6. load shellfish into depuration systems at specified density and by approved method
  7. establish water flow and sterilisation to optimise the purification process and minimise stress to shellfish
  8. observe shellfish for signs  of purging and report incidences where shellfish are not seen to be functioning
  9. maintain environmental conditions within the depuration system to achieve required purification
  10. drain down the depuration tanks after depuration following organisational procedures
  11. rinse shellfish following depuration to minimise risk of re-contamination following depuration 
  12. unload shellfish from depuration tanks in a manner which minimises the stress caused to shellfish
  13. undertake post-depuration processing
  14. remove dead or damaged shellfish, minimising disturbance to the remaining shellfish
  15. place shellfish in clean  storage, in preparation for dispatch
  16. clean  depuration facility into a hygienic condition in preparation for the next shellfish batch
  17. complete records in accordance with organisational requirements

Knowledge and Understanding

You need to know and understand:

  1. what the organisational standards are and what may happen if they are not followed
  2. the hygiene requirements associated with the depuration process
  3. your responsibilities under food safety legislation
  4. the principles of shellfish depuration
  5. why shellfish need to be washed both before and after depuration
  6. why it is important to remove dead or damaged shellfish before depuration begins
  7. the environmental conditions required for depuration
  8. the classifications given to shellfish growing areas and how these impact on the depuration process
  9. the legal requirements controlling the depuration and dispatch of shellfish
  10. the signs which indicate that shellfish are purging
  11. HACCP and the critical control points controlling the depuration, storage and dispatch of live shellfish
  12. the hygiene/food safety requirements associated with depuration
  13. how shellfish become stressed and why it is important to minimise the stress caused to shellfish
  14. the storage conditions required to maintain quality of live shellfish
  15. the significance of re-contamination to public health
  16. the legal time requirements for depuration
  17. the legal requirements controlling the dispatch of shellfish
  18. what recording, reporting and communication is needed, how to carry this out and the reasons why it is important to do so
  19. the limits of your own authority and competence and why it is important to work within those limits


Scope Performance

Scope Knowledge





Links To Other NOS

External Links

Version Number


Indicative Review Date

01 Jan 2023





Originating Organisation


Original URN


Relevant Occupations

Manufacturing Technologies, Plant and Machine Operatives, Process Operatives, Process, Plant and Machine Operatives

SOC Code



Fish, Shellfish, Seawater, Health, Safety, Hygiene.