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# Cribbing

Tue, 11 Aug 2009|

Paul DeBartolomeo demonstrates building a box crib to be used in conjunction with an air bag.

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Transcript

It. I'll pull the but -- now what in the training -- in this segment we're gonna discuss the characteristics of -- We're gonna explain the difference between captures that and -- tax. And we're gonna demonstrate how to probably build a box period in conjunction with high pressure air bags. -- -- -- -- -- -- -- Consists of four by four blocks when he -- Four -- four wedges. Eighteen inches. 254 blocks point four inches long. -- -- -- -- -- -- -- -- -- -- Generally speaking most fire departments use dog whisperer or southern pine constructive -- Although these woods are considered to be solved -- they have a maximum load capacity of 500 PSI. They also have the built in safety features they. -- slowly -- give advance warning prior to failure. Given the maximum load capacity of 500 PSI it multiplying it times to contact surface area of the four by war. We come up with a contact load rating of 6000 pounds. So was standard two by two box crib with four points of contact can support 44000 pounds provided each contact point is equally load. The standard two by two box is good for capturing light to moderate loans but it is not intended to be used as a -- stack. Because of its open middle space. The open middle. Causes lower contact surface of the -- to -- when the bags inflated. As that bags -- it's gonna apply lateral pressure to -- -- it may cause the -- back to collapse. A three by three cross -- -- has nine points of contact. Therefore it can support 54000. Pounds as long as each point of contact is equally -- it. The three by three is designed to capture of moderate to heavy loans. It is more designed for lifting. The center span of the three by three -- I created -- support. The lower surface area of the back so as the bag inflates we don't have to worry about the back sagging into the creek. -- we're building a standard -- -- box grid if we're working on dirt or salt routes that successful. We -- start with a solid base surface -- good foundation of bill. As we build our tears we want to make sure we have forage overhang and each contact point. This overhang in the event that the -- -- begins to crush will cause the would actually expand it will help to prevent complete failure. We have to take into consideration the height of -- -- stack. We don't wanna build our troops back to a ratio of three to one space of the -- that's. One rule doesn't read forwards like that the four bytes. It refers to the footprint between the times. Which if we adhere to the four inch overhang will be a span of sixteen inches so multiplying sixteen inches times three. We come up with 48 issues so -- box -- stack should not exceed 48 inches if we start to build giving any higher than that it becomes on steady. And we could. Have a collapse. What we have here is a -- by cross tide lifts that. It's important we're living with airbags that we finish this -- with a solid top layer of war by force. The solid top -- -- fully support the -- contact surfaces the back. Something we've come up -- it. In little off the solid -- four by fours we -- plywood that basically what it is is three pieces of three quarter inch plywood. -- screwed together. We copies pads to the dimensions in the air back for example there's that is -- -- inches by one inches and as you can see we have listed on the pad. The corresponding -- it goes with the pressure setting -- -- statistics. That go with that back. Simply put on top your -- stack the other solid base to work on in the air bag. It's perfectly on -- What we do is we caught. Why would bats of course spot every bad we have on the apparatus as we see here this that is for use with a four point three -- back. We have all the vital statistics right on the back which makes it easier for the operator at the emergencies. This -- here is cut to fit the six point five on. And again all the vital statistics are right on the back gives us a nice solid platform the live. As with any fire department operation -- pre determined assignments and -- equipment allows for a quick and efficient operation. Many companies. Have assignments for air bag operations. In my company he -- man is assigned to the -- This assignment entails him bring the -- to the rescue scene in -- box trips to support the evolution. As you can -- our system is pre rigged to bring the most widely used -- right to the rescue scene. Are carrying case contains -- by four blocks four by four wedges and two by four blocks. This case can support an initial operation. In addition to carrying case doubles as a plywood that to lift off both. So this carrying case system allows one firefighter transported decent amount of -- to a rescue scene. It's quick and reliable man. -- for the but -- now thank you for watching training --