– Talha Qadir
If you’re going to be hanging off any large structures in the near future, you might want to make sure that your safety gear holds up under pressure.
Carolyn Sparrey, an SFU professor of Mechatronics Systems Engineering, in partnership with JADE Engineers Inc., has examined how energy absorbing lanyards — pieces that connect safety harnesses to structures in many industrial workplaces — uphold their safety features after various types of wear and tear.
Sparrey spoke to the impact her research could have in helping to prevent workplace injury. She told The Peak, “To those working in the field, [lanyards are] their lifeline. It’s the thing that could ultimately save their lives in the case of a fall.”
The study used drop tests conducted at a brand new facility, developed along with BCIT. Sparrey explained that the drop tower setup “is the first of its kind in western Canada that is not at a private company.”
The researchers looked at how various types of damage could affect the performance of the lanyards. The team exposed lanyard to environmental conditions such as cool temperature and precipitation, as well as to damage from cuts. The tests, Sparrey explained, showed that “pretty much their performance was consistent across the board.”
She continued, “There was no obvious effect of environmental damage on the mechanical performance. There was no obvious effect of weld damage or cuts. Even with cuts that were made 50 per cent of the way through [. . .] it still performed as it should.
“Where we did see catastrophic failure was when there was heat damage.”
Sparrey hypothesized that this was because, while cuts leave a functioning portion of the lanyard still intact, heat melts the fibres of the lanyard and “affect[s] the overall mechanical integrity of the system.”
She acknowledged that one of the limitations of the study was that it used a 100 kg steel mass, which doesn’t effectively demonstrate how a moving person affects the dynamic of a fall. In her next round of studies, she intends to use a crash test dummy, which she predicts will absorb part of the energy from the fall and lead to less deployment of the lanyard.
Sparrey also intends to study situations in which a lanyard might wrap itself around a beam or structure. “One of the things were looking at is how we protect against that,” she noted. “What kind of intervention or technology can we put between a lanyard and an edge or a beam so that it doesn’t result in a catastrophic failure?”
Despite these results, Sparrey is cautious of drawing definitive conclusions: “Our overall conclusion for all research is we need to do more studies.”
