National Nuclear Ventilation Forum (NNVF) & Ventilation Working Group (VWG)

About Us


The objective of the forum is to discuss and document good practices relating to nuclear ventilation. The forum is open to representatives from all UK nuclear ventilation industry companies. The mandate of the Forum is to:

  • Discuss and share good practice and issues relating to nuclear ventilation
  • Develop documentation for Standards, Codes of practice and Guidance
  • Discuss and comment on documentation developed by member companies
  • Develop opportunities and materials for training and CPD
  • Promote and disseminate good practice to the UK nuclear industry

The meetings are well attended and provide an opportunity to get involved in the technical issues facing the nuclear ventilation industry. The forum has a number of sub-groups that address specialist areas (e.g. HEPA filters, decommissioning, ductwork) and then bring their findings and new documentation to the forum meetings.

Prior to the forum no common Industry standards existed for nuclear ventilation: each company had developed its ventilation codes and standards. There was an identified need to demonstrate their individual arrangements were at least equivalent to good practice used elsewhere. Common industry standards gives operators and regulators a single reference source, and also enables the supply chain to deliver a more consistent product.

Further guidance will provide:

  •  Reduced design/technical risks from future operations such as decommissioning by improved understanding of good practice methods.
  •  Sharing of developments and innovation

The forum also holds seminars and presentations with the aim to increase the pool of SQEP nuclear ventilation engineers and sharing relevant decommissioning knowledge.


The Ventilation Working Group (VWG) is for Site licensees to discuss the implementation of ventilation practice on their licenced site. Regulators are invited to the meetings as observers.
The VWG guide the NNVF work programme and finally endorse documentation.
This recognises that the licensees are ultimately responsible for what is implemented on their sites, and there is a need for them to determine the requirements for, and to endorse, any documentation and good practice produced.

Programme of Work

Future Programme

  • Supporting ISO/European standards, especially In-situ filter testing and Reactor systems
  • Ventilation Control systems
  • Further Filter specifications
  • Update of the primary guide DG001 to ES_1738, incorporating existing addenda and technical developments
  • Further events to promote Training and CPD (to ensure adequate resources of SQEP nuclear ventilation designers). 

Annual Summary

The NNVF has good attendance (usually around 40) and a membership willing to work together to produce new documentation. The inclusion of the supply chain is a significant benefit, as a large amount of detailed technical expertise now resides only at this level.


The forum has a separate Ventilation Working group, comprising of licensee representatives only, who provide direction for the national forum and formally accept documentation.

The NNVF has made significant progress in reviewing relevant ventilation documents and NNVF documents are effectively being incorporated into the Sellafield Ltd suite of standards. Access to all NNVF member companies has been arranged - addressing wider industry and supply chain concerns.

Learning from Experience/ Operational Feedback

A significant part of meetings is set aside for discussing recent events on sites and developments within the industry and this has been increasing recently.. This is a useful forum for sharing both issues and good practices throughout the industry.

Regulatory Engagement

ONR have used the NNVF/VWG as a method of gaining expert industry feedback and have engaged effectively at a technical level – ONR continue to attend and contribute to discussions.

EA are also now regularly attending and discussions on the development of gaseous environmental standards and codes of practice have been initiated.

Stuart Allen (ONR) recently presented to the NNVF on update to TAG 77 "Supply Chain Management Arrangements for the Procurement of Nuclear Safety Related Items or Services". This was a valuable engagement especially directly with the supply chain, as well as licencee members


Really useful interactions were had with the Nuclear Industry Fire Safety Coordinating Committee – since the last report a member of that group (BRE ltd) has attended NNVF meetings and continues to feed in wider industry practice into our standard approach. This has been a valuable interaction supporting resolution of the fire damper issues in particular.

Useful Documents:

NVF DG001 Ventilation Design Guide issue 1 2009 and Addenda A1, A2, A5 & A9 - these have been replaced by ES_1738_1 Ventilation Systems for Radiological Facilities - Design Guide

NVF DG002 Glovebox Ventilation Design Guide Issue 1 2012

VWG DD/001 Guidance on NNVF papers, issue 1

VWG DD/002 Filter visual inspection guide, issue 1

VWG DD/003Filter Safe Change systems, issue 1

Links to other sites:


Contact Us:

For more information regarding this group please contact the chair:
John Keeton, Chair –
Pete Thompson, Sponsor

Membership Benefits

Gain International Chartered

Use of Designated Letters After Your

Local Branch Network

Conferences, Seminars and Workshops
Nuclear Futures Journal

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