EN 12094-7:2000/A1:2005

Overview

EN 12094-7:2000/A1:2005 (CEN) specifies requirements and test methods for nozzles used in CO2 gas extinguishing systems. It focuses on room protection nozzles that introduce the extinguishing agent into a protected zone. The standard recognizes that nozzle design affects discharge rate and pressure drop in the piping network and that CO2 normally arrives at the nozzle as a two‑phase (liquid–gaseous) mixture, expanding into a gas or a gas‑and‑dry‑ice mixture depending on nozzle type. Amendment A1 (2005) narrows the scope to room protection nozzles and clarifies testing and intended use for components in building gas extinguishing systems.

Key topics and requirements

• Scope and applicability
  • Intended for room protection nozzles in CO2 systems; not applicable to local application nozzles.
  • Covers components used as part of complete gas extinguishing systems installed in buildings.
• Nozzle performance factors
  • Influence of nozzle design on discharge rate and pressure drop in the piping network.
  • Behaviour of two‑phase flow arriving at the nozzle and subsequent expansion into gas or gas‑and‑dry‑ice.
• Distribution characteristics
  • Tests for distribution of CO2 in the protected volume are specified (referenced in clause 5.4 as amended).
• Test methods and set‑up
  • Standard specifies test methods and the required test set‑up (figures renumbered in the amendment); it provides guidance for practical laboratory testing of room protection nozzles.
• Regulatory context
  • Prepared by CEN/TC 191 and supports essential requirements of EU Directive 89/106/EEC (see informative Annex ZA).

Applications and who uses it

• Nozzle and system manufacturers - to design and validate CO2 nozzles that meet European requirements.
• Testing laboratories and certification bodies - to perform standardized performance and distribution tests.
• Fire protection engineers and system designers - to select appropriate nozzle types and size piping networks accounting for discharge rates and pressure drop.
• Specifiers, consultants, installers, and facility safety managers - to ensure installed CO2 systems use compliant nozzles for room protection.
• Regulatory authorities and compliance teams - for conformity assessment against CEN requirements.

Related standards

• EN 12094 series (other parts) - complements Part 7 by covering broader aspects of fixed firefighting systems and CO2 system components.
• Annex ZA of EN 12094-7 links the standard to EU construction/product directives.

Keywords: EN 12094-7, CO2 nozzles, fixed firefighting systems, gas extinguishing systems, test methods, nozzle requirements, two‑phase flow, room protection nozzles, CEN, Amendment A1.