Overview
ISO 16976-5:2023 - "Respiratory protective devices - Human factors - Part 5: Thermal effects" provides essential human-factor and physiological data on how respiratory protective devices (RPD) affect local and whole‑body thermal responses. It is one part of the ISO 16976 series and addresses surface temperatures, inhaled gas temperature and humidity effects, respiratory heat exchange, and how RPD influence overall heat balance for healthy adults (men and women) aged 20–60 years.
Key topics and technical content
- Local thermal effects: analysis of skin contact with RPD (face, head, torso, hands), including the influence of contact pressure, surface structure, material mass and thermal properties.
- Hot and cold surface criteria: guidance and exposure thresholds for discomfort, pain and tissue damage when skin contacts hot or cold RPD components. The standard references ISO 13732‑1 (hot surfaces) and ISO 13732‑3 (cold surfaces) and provides burn and cooling thresholds for common materials (e.g., metals, plastics, ceramics) and for different contact durations.
- Respiratory tract and breathing gas effects: information on thermal effects of inhaled gas on airways and lung tissue, and on how breathing‑gas temperature and humidity alter respiratory heat exchange. The document notes device type, material and function (e.g., chemical reactions, compressed air expansion) influence gas temperatures delivered to the user.
- Whole‑body heat balance: considerations for respiratory and skin surface heat exchange, increased metabolic heat production, thermoneutral conditions, heat stress and cold stress. The standard cross‑references methods such as IREQ (ISO 11079) and PHS/ISO 7933 for physiological strain assessment.
- Scope limits: data apply to healthy adults aged 20–60 and emphasize individual sensitivity variability and task/activity dependence.
Practical applications and users
ISO 16976-5:2023 is useful for:
- RPD designers and manufacturers - to select materials, insulation and component designs that minimise thermal risk (burn, frostbite, discomfort).
- Test laboratories and conformity assessors - for developing thermal‑safety test protocols and interpreting surface-contact and inhalation‑temperature data.
- Occupational health & safety professionals and ergonomists - to assess heat and cold stress risks when RPD are used in extreme environments.
- Standards developers and procurement specialists - to specify thermal performance and compatibility requirements in PPE specifications for industry, emergency services and military use.
Related standards
Keywords: ISO 16976-5:2023, respiratory protective devices, thermal effects, RPD, heat stress, cold stress, skin contact thresholds, breathing gas temperature, PPE design.
