A construction site accident at Virginia Tech last week, once again highlights the importance of safety measures at commercial construction sites.
Five people suffered non-life threatening injuries, when a hydraulic scaffold collapsed and fell about 25 feet. No word yet on the cause of that accident.
Falls by workers are one of the major causes of fatalities on construction sites. And while there have long been fall prevention regulations for commercial construction, OSHA recently implemented safety requirements for RESIDENTIAL construction as well.
A Virginia Tech professor is working on a new approach to keeping workers safe on the job.
We’re standing in one of those new green developments where entire neighborhoods adhere to a set of environmentally safe standards. Some of the new houses in this Blacksburg subdivision are already lived in, others are half complete, their wood skeletons suggesting rooms and staircases.
“So that’s another thing I’m interested in is, how do you take a house, especially something like green building and you want to think about safety of the occupants, environmental effects, energy efficiency but what about safety of the workers?" asked Virginia Tech's Daniel Hindman, Associate Professor of Wood Engineering.
Hindman is editor of a Journal called ”Wood Design Focus.” He’s part of a team exploring better ways to cut down on falls by construction workers.
“And I talked to some of the safety managers and they said, there were some workers who had fallen, took it upon themselves to do ‘tool box talks,’ to say to the other workers, ‘I don’t care how macho you are. If you fall it’s going to hurt. It’s going to hurt you and it’s going to hurt your family.
New safety rules on fall prevention for commercial construction went into effect in 2011. For residential construction workers OSHA phased in similar rules March 15 of this year.
" They changed the rules to say, just like commercial construction if you’re working 6 feet or over you must be harnessed to something, you must have a guard rail or you must have a net underneath you," he said.
Hindman says a harness is key to safety at heights, but what it’s attached to makes all the difference in breaking a fall.
“Most of the roofs on these buildings you see are made with trusses. So they’re 2x4s, they’re connected with metal plates; they kind of form a triangle with some zig zag members in between. Trusses are used a lot in the construction industry because they’re light, they ‘re structurally efficient, and they can carry a lot of load for a little bit of weight.
Hindman’s team designed a series of connected triangular roof trusses to spread out the load and break a fall without breaking the support structure.
“And you have this bracing it spreads the load ou so that all the trusses are carrying that load. If you have just one or two or if you don’t have enough bracing, the trusses are just going to fall over just like dominos. Reporter: And the worker will be injured. DH: And the worker will strike the ground. You know, we don’t want any falls to happen but the whole purpose of a fall protection system is if a fall happens then the lifeline and harness do their job and they lower the force on the worker. The worker takes a little ride, they go over the side, they’re rescued by their friends, the structure holds up and doesn’t collapse on top of them. They can inspect the structure, make sure everything’s OK and go back to work”
Hindman says the test of whether his team’s model works will be if construction workers actually use it.
"There’s something called safety culture. It’s not just making a better mouse trap, it’s not just coming up with a better idea. It’s getting workers to use it. And to get workers to use it is has to be easy to use it has to save them time. It has to help them with their job."