Respiratory Protection Standards
Guide to Respiratory Protection Australian Standards
AS/NZS 1715:2009 – Selection, Use, and Maintenance of Respiratory Protective Equipment
This standard outlines principles of respiratory protection, including selection, use, and maintenance of RPE. It defines the protection factor – the ratio of contaminant concentration outside vs. inside the respirator.
Topics covered include hazard identification, risk assessment, respiratory protection programs, RPE selection and limitations, medical considerations, training, and fit testing procedures.
AS/NZS 1716:2012 – Respiratory Protective Devices
This standard defines performance, manufacturing, and testing requirements for respirators, including those used in atmospheres with harmful substances or low oxygen levels.
Different Classes for Particle Filters
| Class | Description |
|---|---|
| P1 | For mechanically generated particulates commonly encountered in industry |
| P2 | For both mechanically and thermally generated particulates |
| P3 | For all particulates including highly toxic materials (requires full-face respirator or PAPR) |
Types of Gas Filters
Filters are designated by letters that indicate the substances they protect against, with class numbers showing absorption capacity.
- Type A – Organic gases and vapours
- Type B – Inorganic gases and vapours (excluding CO)
- Type E – Sulphur dioxide and acid gases
- Type G – Organic compounds with low vapour pressures
- Type K – Ammonia and derivatives
- Type AX – Low boiling point organics (<65°C)
- Type NO – Oxides of nitrogen
- Type Hg – Metallic mercury
- Type MB – Methyl bromide
- Specific chemicals – Named individually when not covered above
Colour Codes for Filters
| Type | Colour Code |
|---|---|
| A | Brown |
| B | Grey |
| E | Yellow |
| K | Green |
| O | White |
| NO | Blue |
| Hg | Red |
| AX | Brown |
Facial Fit – TIL (Total Inward Leakage)
Facial fit tests ensure a secure seal between the respirator and the face. TIL testing verifies this seal. Below is a breakdown of filtration efficiency by respirator class and type.
| Respirator Type | Filter Class | Filtration Efficiency |
|---|---|---|
| Non-powered Half Face | P1 | 80% |
| P2 | 94% | |
| Non-powered Full Face | P3 | 99.95% |
| Powered PAPR | P1 | 95% |
| P2 | 99% | |
| P3 | 99.95% |
Fit Testing
Proper fit is crucial for effective protection. AS/NZS 1715 requires tight-fitting respirators—including disposable, half-face, full-face, and powered/air-fed types—to undergo fit testing as part of any respiratory protection program.
Airborne Particulate Sizes and Hazards
Dusts and aerosols vary in size and source. The following chart outlines the typical size range of various airborne substances encountered in workplaces.
| Particle Size Range (μm) | Examples |
|---|---|
| 0.0001–0.001 | Viruses |
| 0.001–0.01 | Oil mist, smoke |
| 0.01–0.1 | Tobacco smoke, fine dust |
| 0.1–1.0 | Atmosphere dust, welding fumes |
| 1.0–10 | Industrial dust, cement dust, coal dust, bacteria |
| 10–100 | Pollen, textile dust, asbestos |
| 100–1000 | Glass fibres, cutting dust |