NIOSH issues rules to protect underground workers in emergencies
These self-contained self rescuers protect workers exposed to toxic concentrations of fumes, gasses, or smoke, or from confined areas where there is insufficient oxygen during emergencies.
The apparatus consists of a mouthpiece connected to a small container by a breathing hose. The container provides either a supply of compressed oxygen with a chemical system for removing carbon dioxide or a store of chemicals that react to form oxygen and remove carbon dioxide when the device is activated. It is carried on a worker's belt or stored nearby for emergency use.
The devices are used in industries where work is performed underground or in confined spaces such as tunneling operations in construction. They are also used by the Navy and Coast Guard crews for emergency escape from confined work spaces below deck.
The new requirements for testing and certification of closed-circuit escape respirators were set by the National Institute for Occupational Safety and Health. They include:
- Improved performance measures to ensure that the respirators are reasonably rugged since they are used in relatively harsh environments.
- A new capacity rating system in which devices will be tested and certified on the volume of usable oxygen they supply. The previous rules were based on the duration of time the devices were expected to provide oxygen. But "in an actual emergency escape, a user may use up the oxygen supply in a shorter time than someone using the device in a test under laboratory conditions," NIOSH explained.
- New design requirements that will allow NIOSH in field evaluations to check units to determine whether harsh working conditions or harsh treatment have diminished the performance of the units and remove those with defects or damage.
- Upgraded testing standards with more stringent verification of the quality and quantity of breathing gas supplied by the devices to establish a more reliable testing process using a mechanical breathing simulator rather than human subject.
The rules were announced March 8 and take effect 30 days later. However, manufacturers will be allowed to manufacture and sell previously approved closed-circuit escape respirators for three years, giving them time to meet the new requirements.
Read more at the WorkersComp Forum homepage.
April 16, 2012
Copyright 2012© LRP Publications