ISO 3941:2007

Overview

ISO 3941:2007, titled Classification of Fires, is an international standard developed by the International Organization for Standardization (ISO). This standard categorizes fires into five distinct classes based on the nature of the burning fuel. The classification system is essential for guiding effective fire-fighting strategies, especially when selecting the appropriate type of fire extinguisher. First published in 1977 and significantly revised in this second edition, ISO 3941:2007 remains a key reference for fire safety professionals and organizations worldwide.

Key Topics

• Fire Classification by Fuel Type
  ISO 3941:2007 establishes five classes of fires:

  • Class A: Fires involving solid materials, typically organic in nature, that burn with glowing embers.
  • Class B: Fires involving flammable liquids or liquefiable solids.
  • Class C: Fires involving gases.
  • Class D: Fires involving combustible metals.
  • Class F: Fires involving cooking media, specifically vegetable or animal oils and fats used in cooking appliances.

• Purpose and Scope
  The standard aims to simplify communication about different fire types and enhance the selection of suitable extinguishing methods and equipment.

• Exclusion of Electrical Risk Fires
  ISO 3941:2007 does not define a separate class of fire involving electrical risks, focusing instead solely on the fuel source.

Applications

• Fire-fighting Training
  The classification system enables fire safety instructors to teach responders how to recognize fire types quickly and choose the correct extinguisher, improving safety and effectiveness.

• Fire Extinguisher Design and Labeling
  Manufacturers use ISO 3941 classifications to label fire extinguishers, ensuring users can easily identify extinguishers appropriate for specific types of fires.

• Safety Regulations and Compliance
  Regulatory bodies and safety inspectors reference ISO 3941 in developing workplace safety protocols, building codes, and fire safety standards.

• Emergency Response Planning
  Facilities incorporate this classification when designing their fire safety plans, including placement of extinguishers and staff training for industrial, commercial, and residential environments.

Related Standards

• ISO/TC 21 – Equipment for Fire Protection and Fire Fighting
  This technical committee oversees standards relating to fire protection equipment, including fire extinguishers and suppression systems.

• ISO 11601 – Fire Extinguishing Media
  Standards specifying the classifications and characteristics of extinguishing agents often align with ISO 3941 fire classes.

• NFPA (National Fire Protection Association) Standards
  While regional, NFPA standards often complement ISO 3941 by providing detailed requirements for fire safety systems and fire extinguisher classifications.

• IEC Standards on Electrical Equipment Safety
  For fires involving electrical hazards, standards from the International Electrotechnical Commission (IEC) provide guidance distinct from ISO 3941's fuel-focused classification.

By adopting ISO 3941:2007’s fire classification framework, fire safety professionals and organizations can enhance hazard recognition, improve extinguisher effectiveness, and promote safer fire-fighting practices across diverse environments. The clear, practical approach of this standard supports global harmonization in fire safety management.