Breathing air connections are accidents waiting to happenConcerns have been raised that it is too easy to connect breathing air apparatus into other air and gas supplies, with potential for serious accidents or even fatalities. Mark Simms reports on the problem.
Asafety and health information bulletin issued in the US in 2004 looked at deaths involving the inadvertent connection of airline respirators to inert gas supplies. The report highlighted several case studies based on investigation reports from 1984 through to 1995, and more recently from the Bureau of Labor Statistics (LBS), and concluded that coupling compatibility problems and lax supervisory oversight were major factors in the inadvertent connection of airline respirators to inert gas supplies.
Surely, though, in 2013 these problems are things of the past? Well, it seems not. Too many breathing air installations are still using generic couplings that could be connected to a multitude of different media. There are safety norms covering connections for breathing air (EN 12021, EN 139, EN 1385 and others) but they are not yet legal requirements. There is guidance from various sources on the quality of the air supply, the quality on the connector and on the need to properly label a breathing air supply, but very little on the need for a unique connection interface.
But then, you might wonder, if the above advice is followed, is there really a need for the added expense of a unique connector? Well, regardless of how well a connection is labelled, inadvertent connection can still happen. People may be highly skilled in their own jobs, but in an emergency situation they are certainly not going to be experts at connecting a breathing line. Even outside of emergency situations, in routine tasks in manufacturing or maintenance tasks, there is still the risk of inadvertent connection to the wrong line.
The US report highlighted a number of case studies. One was of an employee using an air hammer to chip residue out of a furnace at an aluminium foundry. He was wearing an airline respirator. Two compressed gas lines with universal access couplings were attached to a nearby post: one was labelled ‘natural gas’ and the other had a paper tag with the word ‘air’ written on it. However, this line actually contained pure nitrogen. A splitter diverted one part of the gas stream to the air hammer and the other part of the stream to the airline respirator. The employee was asphyxiated and killed when exposed to pure nitrogen.
Areas such as painting, cleaning, some manufacturing operations and abrasive blasting surely need a unique breathing air connection. The problem, though, is that most installations used today employ standard compressed air connectors, and these can too easily be connected to the wrong media, despite what might be deemed to be adequate labelling on the connection points.
If standard compressed air connectors are inadequate to protect users or breathing air lines, what is the alternative? Safe solutions have been available for many years, with unique mechanical designs that prevent accidental cross media connection. This adds a vital layer of safety above and beyond the current requirement for adequate labelling and adequate quality.
Do we have to wait for a serious accident or a death in this country before action is taken? Even if safer couplings are slightly more expensive, it has to be cheaper to prevent an accident than to face the litigation after the event. On a purely ethical argument alone, when it comes to safety, ‘adequate’ surely should never be good enough.
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