Respiratory protective equipment (RPE) protects from airborne hazards such as a gas, fume, mist, dust or vapour. Respiratory equipment removes harmful particles and, along with breathing apparatus (BA), provides clean air for the worker. Worldwide standards In the US, respiratory protective equipment standards are OSHA - 29 CFR 1910.134. The European Union has several, including: EN149 (disposable filtering face piece respirators), EN 405 and 140 (half masks), EN136 (full face masks), EN141 (gas/vapour combination filters), and EN143 (particulate filters). Australia and New Zealand use AS/NZS Standard 1715. Canada uses CSA Standard Z94.4-03. These standards provide a foundation for your respiratory protection programme. Types of respiratory equipment Dust masks are composed of a filtering medium that traps airborne contaminants before they can reach the user’s respiratory system. Disposable masks provide effective protection against certain airborne hazards, but they are limited. Toxic gasses and vapours are able to pass right through a dust mask. Dust masks do not increase or supply oxygen. An oxygen level below 19.5 percent is known as oxygen deficient, and a dust mask provides no protection. Air purifying respirators provide protection by filtering the air supplied to the wearer. They work by drawing inhaled air through a filtering medium which reduces the contaminant level in the air before inhalation. Powered air purifying respirators (PAPR) rely on filters just like the negative pressure air purifying respirators. They are equipped with a battery powered blower to provide a positive pressure inside the mask. PAPR are more comfortable for long term use and have higher APF. Air supplying respirators provide protection by blocking ambient air. They supply stored air or oxygen to the wearer. The air or oxygen is supplied from a source different to the atmosphere the person is working in. This might be a compressor, cylinder or air line.