ISO 16321-2:2021

Overview

ISO 16321-2:2021 specifies additional material, design, performance and marking requirements for eye and face protectors used during welding and related techniques. It supplements the general requirements in ISO 16321‑1 and focuses on hazards common to welding: optical radiation (UV, visible, IR), impacts from flying particles, hot solids and thermal exposure. The standard applies to welding helmets, hand shields, goggles, spectacles and associated frames and mountings used in industry, educational establishments and occupational‑type DIY tasks. ISO 16321‑2 is the first edition (2021) and replaces the earlier ISO 4850:1979.

Key topics and technical requirements

• Field of view: Specifies minimum unobstructed view requirements when worn (measured on headforms) to maintain safety and situational awareness.
• Welding filters: Defines spectral and luminous transmittance requirements across UV, visible and IR bands and assigns scale numbers (e.g., W1,2 … W16) corresponding to shade / luminous transmittance levels. Blue‑light transmittance limits are also required.
• Automatic welding filters (auto‑darkening): Includes requirements for transmittance, luminous variation over time, variation between states, switching and holding times, manual control of dark shade number, thermal resistance and optional optical sensitivity and surface‑damage resistance tests.
• Mechanical and physical tests: Covers robustness (static load, drop tests), resistance to UV, penetration by hot solids, electrical insulation (for helmets and hand shields), light tightness and dimensions/mass limits for hand shields.
• Marking and manufacturer information: Mandates markings on filters and protectors (identification, scale number, manufacturer) and the information that must be supplied with the product.
• Temperature range: Intended performance range is −5 °C to +55 °C, with specific tests at temperature extremes to validate protection.

Applications and who uses this standard

• Manufacturers of welding helmets, auto‑darkening filters, welding goggles and shields to design, test and certify products for international markets.
• Safety engineers and procurement teams in manufacturing, fabrication, shipbuilding and construction specifying compliant PPE.
• Test laboratories performing optical and mechanical test methods (see ISO 18526 series for methods).
• Educators and institutions that provide welding training and need to ensure student PPE meets occupational standards.
• Occupational health and safety professionals creating PPE policies for welding and related techniques.

Related standards

• ISO 16321‑1:2021 - General requirements for eye and face protection
• ISO 18526 series - Test methods for optical, physical and mechanical properties
• ISO 4007 - Vocabulary for eye and face protection

Keywords: ISO 16321-2, welding eye protection, welding filters, welding helmets, automatic welding filters, PPE for welding, optical radiation, welding safety.