Across heavy industry, high pressure hoses are used for containing a variety of different substances in the form of liquefied gases and compressed air. However, as BSC’s Michael Rowe explains, “Measuring the potential risk of an on-site injury occurring from a high-pressure hose is mainly a matter of measuring the frequency of their usage — which is high.”
“To put it bluntly, a quick change in pressure behind a flexible hose application can be life-threatening,” cautions Michael. “If a pressurized hose experiences a sudden spike or release in pressure, the hose can whip or flail around in similarly unpredictable movements at very high speeds. This creates an extremely dangerous situation that is hard to contain.”
Michael notes that the point of connection where two hoses are joined or there is a valve backed by compressed air are the key areas that require secure safeguarding.
“If a worker runs the air pressure where there are hoses connected, and the hose comes apart, that is when there is the potential for the hose to whip,” he emphasises. “The air pressure on these hoses peaks at around 90-100 pounds per square inch which is the amount of force that pressure is containing. Subsequently, unguarded hose connections can do significant damage to personnel nearby or the structural integrity of its surroundings.”
Following several injuries and fatalities where the cause was determined to be a malfunctioning pressure hose, the Australian federal government published a safety alert on July 1, 2020, reminding employers of the importance of installing a safety whipcheck on pressurized air hoses, in order to safeguard employees from the dangerous threat of hose whip.1
To visualise how a whipcheck mechanism fits together, Michael describes that a typical whipcheck features spring-loaded loops in the cable ends that are easily opened to pass over the couplings, providing a firm grip on the hose.
“The claw coupling will be around 50mm in diameter, relatively to the hose which would be around 20mm thick.”
Digging a little deeper into the issue, Michael discusses the mechanics behind a whipcheck and why it is critical to site safety to ensure that all pressurized air hose equipment is safeguarded.
He also makes some production and installation suggestions to get started with safeguarding hoses, referring to knowledge he obtained through one of BSC’s suppliers, Dixon, a well-known manufacturer of hose coupling and retention devices for safeguarding these types of applications.
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