ISO 3873:2025

Overview - ISO 3873:2025 (Industrial protective helmets)

ISO 3873:2025 is the International Standard specifying physical and performance requirements, test methods and marking requirements for industrial protective helmets. The second edition updates and replaces ISO 3873:1977 and introduces two helmet types:

• Type I - protects the upper part of the head from impacts typical in industrial settings (e.g., falling objects).
• Type II - provides broader protection (front, side and rear) against impacts such as falling objects or short falls (note: Type II is intended for falls from standing or low height, up to about 1 m, and is not designed to prevent serious injury from uncontrolled or long-distance falls).

This standard is published by ISO/TC 94 (Personal safety - Personal protective equipment) and outlines mandatory and optional tests, conditioning procedures, marking and user instructions for safety helmets.

Key topics and technical requirements

ISO 3873:2025 covers the following technical areas:

• Materials and general construction requirements for helmet shells, liners and attachments.
• Performance tests, including:
  • Impact energy attenuation (new for Type II) - verifies the helmet’s capacity to reduce transmitted impact forces.
  • Striker drop test and headform drop test for impact performance.
  • Resistance to penetration - evaluates protection against sharp falling objects.
  • Resistance to ignition - replaces previous flame-resistance provisions.
  • Dynamic strength of the retention system and dynamic stability (Type II).
  • Buckle release, and optional tests such as low-temperature, artificial ageing and electrical performance.
• Test requirements and conditioning - sample selection, environmental conditioning (cold, heat, wet, ageing) and test schedule.
• Marking and instructions for use - mandatory helmet markings and user guidance for safe selection and maintenance.

Practical applications and who uses this standard

ISO 3873:2025 is used by:

• Helmet manufacturers and designers to develop and certify industrial protective helmets.
• Test laboratories and certification bodies to perform standardized testing and conformity assessment.
• Procurement officers and safety managers to specify compliant helmets for workplaces (construction, manufacturing, utilities, mining).
• Regulators and occupational health professionals to reference accepted performance criteria for PPE. Practical benefits include improved product safety, consistent testing protocols, and clearer guidance on helmet selection-especially the limitations of Type II helmets in fall scenarios. Selection of helmets for work at height should be part of a comprehensive fall-risk system, particularly when working above 2 m.

Related standards and context

ISO 3873:2025 is aligned with ISO/TC 94 work on personal protective equipment and reflects collaboration with electrotechnical committees where relevant (electrical performance testing). Users should also consider complementary national and regional PPE standards and fall-protection regulations when specifying helmets.

Keywords: ISO 3873:2025, industrial protective helmets, safety helmets, PPE standard, Type I helmet, Type II helmet, impact energy attenuation, retention system, penetration resistance, striker drop test.