ISO 17420-2:2021

Overview

ISO 17420-2:2021 - Respiratory protective devices - Performance requirements - Part 2: Requirements for filtering RPD specifies performance, testing and component requirements for filtering respiratory protective devices (RPD) intended for workplace use. The standard defines how filtering RPD are classified and evaluated to protect wearers from hazardous atmospheres and environments. It also covers requirements for RPD elements and replacement components and includes testing schedules, marking and manufacturer information requirements.

Key topics and technical requirements

ISO 17420-2:2021 addresses the main performance and verification elements needed for reliable filtering RPD:

• Classification and protection class determination - procedures to determine protection performance, including Total Inward Leakage (TIL) methods.
• Breathing performance - evaluation of work of breathing, breathing resistance (peak pressure) and elastance for both unassisted and assisted RPD.
• Contaminant limits and safety conditions - provisions for CO concentration limits and inhaled air temperature/humidity when relevant.
• Connections and connectors - strength and compatibility requirements (including requirements for RPD with standardized connectors and low-pressure hoses).
• Reliability and pre-conditioning - assessment of durability and pre-conditioning (sequential/non-sequential) before testing.
• Elements and components - specific requirements for filters, hoses, visors and other separable parts; performance when using prefilters.
• Validation by practical performance - donning/doffing, communication (speech and hearing), eye irritation, fogging and ergonomics.
• Testing, marking and information - test schedules, inspection methods, marking requirements and minimum information manufacturers must supply.
• Supporting annexes - reliability guidance, example FMEA, test schedules and normalization of test results.

Applications and who uses this standard

ISO 17420-2 is practical for organizations involved in respiratory protection lifecycle:

• Manufacturers and designers of filtering RPD and replacement filters - to design and verify products meet international performance requirements.
• Testing laboratories and conformity assessment bodies - to perform standardized tests, TIL measurements and reliability assessments.
• Occupational health & safety professionals and procurement teams - to select appropriate filtering RPD for workplace hazards and ensure supplier compliance.
• Regulators and certification schemes - to reference technical requirements for approval and market surveillance.
• Maintenance and training providers - to understand functional limits and required user information.

Related standards

• Part of the ISO 17420 series on respiratory protective devices. Users should consult other parts of the series and relevant national or industry standards for complete certification and workplace use guidance.

Keywords: ISO 17420-2:2021, respiratory protective devices, filtering RPD, performance requirements, Total Inward Leakage, breathing resistance, filter requirements, RPD testing, workplace respiratory protection.