Guidance and recommendations on design, selection and installation of vents to safeguard the structural integrity of enclosures protected by gaseous fire-extinguishing systems (+A1:2026)

BS EN ISO 21805:2023

British Standards Institution
Guidance and recommendations on design, selection and installation of vents to safeguard the structural integrity of enclosures protected by gaseous fire-extinguishing systems (+A1:2026) Download document

Document Status

Current

Supplement

Mechanical & Electrical Supplement

Series

BS EN ISO

Abstract

Sets out the design, selection and installation requirements for vents used to safeguard the structural integrity of enclosures that are protected by fixed gaseous extinguishing systems. Covers: use and limitations, safety, pressure-relief venting and post-discharge venting, acceptance, service and maintenance.

History

Supersedes BS EN ISO 21805:2023. Identical to ISO 21805:2023, incorporating amendment 1:2025. Amendment dated 15 January 2026 - Implementation of ISO amendment 1:2025 with CEN endorsement A1:2026.

ISBN

9780539334364

Subjects

  • Ducts/flues/pipes
  • Special subject areas
  • Fire
  • Building services

Publisher History

With over 100 years of experience the British Standards Institute is recognised as the UK’s National standards body. Their committees work with the manufacturing and service industries, government, businesses and consumers to facilitate the production of British, European and International standards.

Information

NBS

NBS has produced specification systems and information products for construction industry professionals for more than 40 years. The National Building Specification is the recognised UK national standard and is used by over 5,000 organisations. NBS is part of RIBA Enterprises Ltd.

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