Back arrowBack to FAQs

Why aren't electronic nozzles mentioned in active fire suppression system (AWFSS) British Standards but are in American Standards?

The British standard for water mist systems is a code of practice. A code of practice contains recommendations and supporting guidance, where the recommendations relevant to a given user have to be met to support a claim of compliance. Users may also justify the substitution of any of the recommendations in a code of practice with practices of equivalent or better outcomes. Therefore innovative products can remain compliant with BS 8454.

This is one of the principles of standardisation, as per the standard for standards (BS 0:2021). BS 8458 must ensure it is:

f) not unduly restrictive (e.g. such as might result in stifling competition or impeding innovation; provisions should, as far as possible, be written in terms of performance);


Further details:

The UK watermist standard is out of date and should have been updated in 2020. All British Standards should be subject to review at least every five years. BSi has confirmed that electronic nozzles will be included in the update of the Standard. 

The development time for a new British Standard typically takes many years, as it often requires consensus from existing manufacturers. All British Standards are subject to review at least every five years, as a result, Standards tend to lag behind novel products. Furthermore, the European Standard is set to supersede the British Standard.

A proposer of a new standard, or even a revision of an existing one, must be able to demonstrate a need for any proposed addition and is therefore also reliant on some market adoption.

US Standards Timeline:

  • July 2020: Plumis made a public input for the 2023 Edition, part of their 3 yearly mandatory updates of NFPA standards
  • September 2020: Plumis was invited to present/explain/answer questions to their public input to the committee
  • November 2020: Plumis asked to listen in to the Draft Standards meeting (which is open to public)
  • May 2021: Plumis resubmitted a modified public input because of the feedback from the committee's discussion
  • September 2021: Final draft meetings held by NFPA where the public input was accepted
  • April 2022: 2023 Edition of NFPA 750 published.

Timeframe to completion: Completed after 1 year and 2 months

The newest edition of NFPA 750 (water mist systems) has been published and includes the use of electronically controlled nozzles in its definitions. The US framework is different. It is much less prescriptive and relies exclusively on certification by a recognised laboratory (like UL) as the means to determine whether a product is fit for purpose, instead of incumbent representatives who may have a conflict of interest. They are also stricter on timing for updates, which MUST occur every 3 years. The UK water mist standard in contrast has not been updated for 7 years.

Critically, the 2023 edition of NFPA 750 recognises electronically operated water mist nozzles as a subcategory of automatic water mist nozzles. The resulting definition of nozzles is therefore the following: Automatic Water Mist Nozzles. Nozzles that operate independently of other nozzles by means of a detection/activation device built into the nozzle. Electronically-Operated Automatic Water Mist Nozzle. Nozzles are normally closed and operated by electrical energy that is initiated and supplied by fire detection and control equipment. 

UK Standards Timeline:

  • 2017: Plumis join the FIA to demonstrate / lobby for innovation
  • 2017: Plumis join BAFSA/FIA watermist working group
  • 2019: Plumis join BAFSA to improve watermist representation
  • 2020: Plumis propose a PAS for an electronically controlled nozzle
  • 2020: BSI stated PAS is too close to BS 8458
  • 2020: RCA accepted to join FSH 18/5
  • 2021: Plumis via BAFSA and the FIA ask FSH 18/5 for scope broadening: little support or impetus to progress
  • 2021: BSI support the publication of part 2 for BS 8458 which includes electronic nozzles
  • 2023: Confirmation that Part 17 of EN 14972 will be published in 2024 and will overlap with BS 8458 resulting in the withdrawal of BS 8458.  Concurrently, confirmation from BSI, in alignment to NFPA, that electronically-operated automatic nozzles are automatic nozzles and therefore within the scope of EN 14972, resulting in the non-publication of BS 8458 Part 2, exclusively for electronically-operated nozzles.

EN 14972 has already had a number of its parts published. Most importantly Part 1, is application agnostic and details all the design, installation and maintenance requirements regardless of the manufacturer and type of nozzle. The European Standard is inclusive of innovation through the use of Annex A.  Parts 2 and onward, address the many existing fire risks/applications through fire test protocols. Plumis are very supportive of the new Standard and looking forward to when it is published.  

Read next - What are electronically controlled water mist nozzles for fire protection?