How much cribbing does everyone get on your MVA's. What type do you use, ie; hard wood of commercially manufactured? We carry 40 pieces of hard wood 4X4X26" and i dont see it being enough. What are everyones thoughts?
If you need different dimensions and shapes, carry different sizes and dimensions...2 x 4, 4 x 4, 4 x 6, 4 x 4 wedges, step chocks, ladder cribbing, and even 2 x 4 shims.
You also need to think about carrying long 4 x 4s (5 or 6-foot lengths and a couple of 8-footers) for bridging voids and to be able to custom-cut bracing at the scene.
Also carry a set of complete extrication struts - Alpha Industries Crutches, Rescue 42's Telecribbing, ResQJacks, etc. Hurst and Paratech also make extrication struts. They are extremely valuable for cars resting on their sides, vehicle overrides/underrides, and other vehicle positions that leave large voids.
Remember that large voids are often easier and quicker to bridge with struts than to fill with cribbing.
The struts (tensioned buttress systems) can provide nearly bombproof stabilization in situations where cribbing doesn't work at all due to the lack of purchase points.
My most recent heavy rescue carried eighty 4 x 4 x 18, twenty 2 x 4 x 18, thirty 4 x 6 x 18, forty 4 x 4 wedges, and two each long 4 x 4s...two four footers, two six footers, and two eight footers.
We once cut a six-footer down to around 4 feet, 9 inches to keep a dash push moved out from a power pole when we could only get one ram at a time in the opening. Every time we collapsed the ram to reposition, the opening would close up. We cut the 4 x 4 and braced the opening from the top, collapsed the ram and inserted the next larger ram, and presto, no springback. The extrication was quickly completed after that improvisation.
Nice info. We have a similar arrangement of hardwood 4x4, 2x4 (18/24”) & wedges, along with step chocks. I recently attended an extrication class and used commercially available cribbing, real nice to work with, heavier than hardwood (2-3x?), but stayed in place. I have been looking for more info on this type of cribbing and look forward to seeing more info on this thread. I agree, the quantity of cribbing needed with the height/length of so many vehicles; particularly SUV’s & HD PU’s w/crew cabs being used as everyday family vehicles.
We have some hardwood cribbing, but it's more expensive and more difficult to find than pine.
The hardwood has a higher crush strength, but you're not going to get anywhere near the crush strength of pine on an average car wreck.
We've found that the pine has an advantage that is not generally recognized - it is easy to get a "bite" into it with the sheet metal lip under the car's rocker panel, the bottom edge of bus sheet metal siding, etc. It may leave a mark in the cribbing but it makes the vehicle more stable with less time and effort.
The 8 footers are useful for several other things...
They can be used with ratchet straps as tensioned buttress systems if you don't have a set of stabilization struts.
They can be used as a crease bar for roof flaps. Roof flaps are making a comeback due to the increasing difficulty in cutting the fortified steels in roof posts.
They can be used with a plywood sheet and a few nails to create a hasty bridge over a deep ditch.
They can be used to support a car that wrecks into a deep ditch or an open trench.
They can be used with two box cribs to support the high end of a vehicle that has partially overridden another vehicle while leaving a crawl space for accessing the patients in the bottom vehicle. This bridge technique can also be used for heavy objects, especially large pipes at construction accidents or tractor-trailer wrecks/loose cargo.
They can be used to bridge lip slides and support the top of the sheeting panels at a trench rescue.
They can be used as hasty raker shores for structural collapse.
Long cribbing isn't going to be used every day, but it is important to have the capability.
When you need it, nothing else will really do the job.
Ben-I've read some interesting info lately about hardwood vs softwood cribbing. After an ongoing company extrication training I realized we don't have enough and am trying to figure out best choice. We cover a fairly rural area with alot of farms, but also have a major interstate highway just across the river from our district and the major east/west rr going through town (no x-ings), 2 derailments in the few years since I moved here, same exact spot. 3 x's a charm right?
I'd be interested to hear your experience with both. Most likely not buying the commercial synthetic cribbing. The short of what I've read;
Softwood: Several comments similar to yours about a bite and also the ability to see & HEAR impending failures, more predictable. Relatively low crush strengths though for HD cribs such say over 25T. I know, small chance we will ever see that kind of load, better to be prepared.
Hardwood: Certain species have a huge gain in crush strength, capacity & will compress to a certain point & stop, but sudden & catastophic failure without warning signs. Heavy & harder to carry distances.
We carry almost exclusively pine cribbing. It is readily available, inexpensive, and a little lighter than hardwood. Good cribbing boxes are much more about carrying enought to do the job and how you build the cribbing boxes than what kind of wood you use.
I've seen some pine cribbing that was damaged and tossed after the call, but I've never seen a load fall or a cribbing box fail due to the type of wood used in 35 years of running wrecks.
You never carry to much cribbing. Cribbing is a disposable item and we have followed the USar teams in switching to a soft wood. I have had hardwoods fail without warning in lifting evolutions. The Rescue Squad carries Ninety-six (96) 4"x4"x18" , Twenty-Four (24) 4"x4"x18" USAR wedges, Twenty-four (24) 2"x4"x18" Douglas Fir. All in Milk crates, each with eight (8) 4x4s, two (2) wedges and two (2) 2x4s - easy to carry - a box crib in each one. We also carry twelve (12) 6"x6"x24" Douglas Fir and Two (2) 6"X6" wedges. Four (4) 2"x4"x96", Ten (10) 4"x4"x96", Six (6) 4"x4"x144", Four (4) 2"x12"x144" for extra buttress stabilization or shoring and for uprights for trench panels. Six (6) sheets of 1/2" plywood 4'x8' and Four (4) 4'x8' Fin Form panels. There are eight (8) Step chocks carries and 300 extra 4"x4"x18" and wedges stored at the station.