An Illinois fire officer is concerned about hard or soft wood for vehicle rescue cribbing. Here's his question...
Ron,
Recently 2 of our firefighters went to the Vehicle Machinery Ops class and came back claiming that we have to remove all hard wood cribbing and replace it with soft wood.The instructor informed them that hard wood fails without without warning and that soft wood with start to splinter before failing and gives you advanced warning. Its been years since I had the class, but I remember that soft wood was NOT to be used as cribbing. Do you have any knowledge of recent changes?
My response is....
I can't explain exactly what those particular instructors in the class your guys took were getting at. I favor hardwood but have used soft wood then thrown it away if it breaks. Hardwood is sometimes difficult and expensive to buy.
What I can say though is that there is a lot of use of soft wood now for cribbing because US&R teams use it for their building collapse incidents. They actually have a guide written that gives ratings of box cribs and sets a mazimum height for certain loads.
In my seminar, I allow soft or hard wood. I do not allow plastic cribbing other than stepchocks. I don't like or trust any plastic 2x4 or 4x4 stuff even with the notches in the ends.
Visit a website that is from a friend of mine in VT. He is a "genius" in my opinion when it comes to wood. He has some training stuff online where he crush tested cribbing with amazing results.
http://www.sover.net/~branch/Safety.html
Check out the "destructive testing" link he has there on the left.
Ron,
Recently 2 of our firefighters went to the Vehicle Machinery Ops class and came back claiming that we have to remove all hard wood cribbing and replace it with soft wood.The instructor informed them that hard wood fails without without warning and that soft wood with start to splinter before failing and gives you advanced warning. Its been years since I had the class, but I remember that soft wood was NOT to be used as cribbing. Do you have any knowledge of recent changes?
My response is....
I can't explain exactly what those particular instructors in the class your guys took were getting at. I favor hardwood but have used soft wood then thrown it away if it breaks. Hardwood is sometimes difficult and expensive to buy.
What I can say though is that there is a lot of use of soft wood now for cribbing because US&R teams use it for their building collapse incidents. They actually have a guide written that gives ratings of box cribs and sets a mazimum height for certain loads.
In my seminar, I allow soft or hard wood. I do not allow plastic cribbing other than stepchocks. I don't like or trust any plastic 2x4 or 4x4 stuff even with the notches in the ends.
Visit a website that is from a friend of mine in VT. He is a "genius" in my opinion when it comes to wood. He has some training stuff online where he crush tested cribbing with amazing results.
http://www.sover.net/~branch/Safety.html
Check out the "destructive testing" link he has there on the left.
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