How Do You Deflate Tires?

[rmoore]

A Post from Ron Moore, Moderator

The Canadian-based auto extrication group C.A.R.S. recently had quite a controversy as to the best method to deflate tires at crash scenes. Some said DO NOT take away the air. Others said pull valve stems, other cut right through the valve stem with side cutters.

Mike Schmidt of ZMag recommended simply removing the guts of the valve stems to gently lower the vehicle and allow for re-inflation if that were desired by the tow company later.

Others added to the controversy by claiming a perceived 'problem' that deflating tires causes the patient to be moved too much.

I'm writing Part 2 of mycar-on-edge stabilization series for Firehouse. Part 3 will focus on this very topic, 4-wheel stabilization. I can incorporate ideas or feedback into that article.

How do YOU stabilize the vehicle on four wheels sitting on a leve street surface?

[cra539]

Ron, in our area we tend to stabilize the vehicle on level surface on four wheels with 4 step chocks and pull the valve stems off the wheels. We have the same controversy in the dept as you described. We have found the very little movement we MAY have caused as not being a problem. If you make as much contact as possible to the car with the step chock before deflating , the movement, again if any , is minimal. We are open to other methods though and may change to removing the valve inserts.

[Halligan84]

I was always skeptical about deflating tires until I saw a method that seemed to satisfy most concerns. We currently do a wheel well lift and insert the step blocks, we can continue to do this, but once the chock is lightly set, attach a air chuck with an open male fitting to each valve stem and allow the tires to deflate and leave them in place. Once your done, or if you need additional room, get your air hose, attach the chuck and reinflate. Im also looking at attaching some sort of larger bright colored tag to the chuck, just to make sure we don't lose them.

[ResQHero]

I agree w/ Halligan84's method. We have done this exact same thing w/ tire deflation valves both in competition and on the street. We have also attached a small piece of tubing to our step-chocks for the deflation valves to be placed in when not in use. This make's stabilization quick and easy. Insert step-chocks then clip the deflation unit on the valve stem. Upon completion re-inflate tires w/ air line.
We have found that the vehicle "sits" more stable w/ the tires down. If you flatten the tires you take the tires and suspension out of the equation. Tested & true!!

[Phred]

ResQ-

Can you better describe your "tire deflation unit" that you "clip on the valve stem"?

It sounds like a lock-on inflator chuck, but is it? Where did you get them and what is the cost?

Do they work on cars with full wheel covers where the valve stem is sometimes almost flush with the cover? Thankx for the info!

------------------
Phred from Ohio
Phred322@aol.com (http://Phred322@aol.com)

[Zmag]

The clip on chucks are exactly what you want or a valve stem removal tool. Whichever method you use gives you the same results. I am currently tring to out together a set of 4 in a small zippered pouch. Its called the Z-flation kit (imagine that) My problem is getting all of you a good deal. if you can go to Wal-mart and buy all the pieces for $28.00 (which you can) you will never pay me $30 for a kit. But I am working a deal to buy a 1/2 a boxcar load of the little rascals and put together a full kit to sell to you for $20 or so. It will be just a little convienant pouch that anyone can easily carry in their pocket. I'll keep working on it ........ film at 11
Zmag

[RoadwayRescue]

Ok...to answer for ResQ..especially since I came up with them> It's a male 1/4" fitting (ours are paratech to match the rest of our air tools) screwed into an auto lock air chuck. Simple, lets air deflate quickly yet slow enough to be controlled. We attach them to our step-chocks in the manner Q desribed...

[John Prentice]

The general consensus in the C.A.R.S. forum was to crib up to the car, tap the wedges into place and the deflate the tires. Step chocks or box cribbing can be used. No motion should be detected if done correctly. Lifting at the wheel well's to insert the cribbing was deemed an unacceptable procedure and one I have never seen in competition.

[trevor]

A unit down the road from us passed on the idea of a 3-point chock system. This involves the use of 3 step chocks instead of 4. Two are mounted on the off-side of the car (ie: the side where the least rescue operations are to be carried out) and the third chock is placed beneath the B-pillar on the rescue side. We have found that this does make the car more stable than using four chocks and trying to adjust the heights to stop movement.

Till you try it you probably won't believe it!!!!!

It all comes down to the fact that a triangle is the most stable and strongest geometical shape.

This system also helps in the case of a complete side removal where the B-pillar is torn in a upwards movement with a set of jaws.

If you deflate the tires or not, it becomes a unit choice. My unit has discussed this idea and have used it in training but as a rule of thumb it never seems to be used on the road so to speak.



[Note: This message has been edited by rmoore]

[jim]

Hi Ron
I thought the key word here was to stabilize the vehicle. By lowering or raising the vehicle I feel could complicate C spine injuries. What we do is use box cribs or use Kevy Jacks ( scissor jacks with metal plates welded on top & bottom ) to stabilize the vehicle. ( Hi Ron guess who, you should know about the Kevy jacks )
Just 1 f/f opinion.
Jim
cgreene1@rochester.rr.com

------------------

[IRISH95]

1)step chocks
2)apparatus wheel chock
3)center punch to release air thru valve stem

[Jim Greene]

I was just thinking ( They tell me that's dangerous ). What about those new flat resistent tires ( I think Firestone makes them ) ? Do they deflate enough to do the task you are trying to do ? Of what I have heard , they do not deflate all that much . The manufacture says it is very easy to control the vehicle during a blow out. They are made so you can control the vehicle at 55-65 mph very easy . That must mean the vehicle does not drop down all that much.
Just wanted to keep things going here.
Thanks
Jim

[SCCARESCUE]

Ron, We use the step block - wheel well lift method and do not deflate any tires. We have found that when done as a team effort, slowly and well rehearsed, that the movement in the patient area is hardly noticable. Also - we do not attempt any evolutions until EMS has stabilized the patient's c-spine. In a serious crash, rarely do you find all 4 tires still on the same plane or level as they were before the crash. Using the step blocks seems to be the best equalizer we can find. If someone has another way, we are all ears.

------------------
Dan Martelle

[FDTrainer]

Ron - I recently attended an AVET class up here in New York (the same class I first took with you a very long time ago). The instructor said that it is no longer acceptable to deflate the tires. The Instructor claimed that deflating the tires caused more movement than was necessary. My FD has used step chocks for years with much success. Do you have any old friends up at the NYS Fire Academy who could clarify this debate?

[jpm]

i think i had the same instuctor as fd trainer he taught us to cribb up to the car, place blocks at tires and do not remove valve stems. my company has always first stabilized patient, lift wheel well ever so lightly place cribbing securely to frame and pulled valve stems. this has always given us a nice platform to work on. what i noticed about not removing stems was that the cribbing would always come loose when you removed parts and thier was a back and forth movement. as for adapters on valve stems i cant see why dont they let the same amount of air out. i think ill wait until ron lou or amy has an opinion on this before i change anything

[This message has been edited by jpm (edited March 07, 1999).]

[nbfd131]

It our department, we don't deflate the tires we us a hurst 28inch spreader to lift the vehicle a few inches and place the step chocks under the frame and then let the car down so it is supported on the step chocks. This is les time consuming then it seems. Takes less then a minute to do the whole vehicle. Truck just about require you to to a tire deflate though unless you take the time to use airbags.

[Zmag]

Ok, I bit my toungue long enough. I was waiting for someone else to reply first, but I guess it's my turn. NBFD ... You can't be serious, I hope you really don't do that ! The simple practice of grasping the wheel well and a gentle manual lift has pretty well been deemed a no-no, to actualy lift a car one corner at a time with a spreader is totaly unacceptable. The car is not only raising up, but it is also rocking side to side and front to back. Everything we have ever been taught about stabilazation is violated. Once again I cast my vote to crib solid from the ground to a solid part and deflate the tires. There is zero down movement, zero rocking, and zero suspension take-up as we lighten the car by removing body parts and victims. Hurry up with those test results Ron !!

[CHVFC63]

I have read a lot what you all have to say about the plus's to deflating tires, now how about the minus's, there out there, lets talk
Ron what is your thoughts on this, any one else. We do not practice deflating tires, some of our members want to??

[Zmag]

Ok, the minus of deflation as I see them

# 1 .. It destroys the tire ... False. If done properly with the proper tools the tire is totaly unaffected. The proper tools include, deflation tools the same as you mechanic uses to change tires, valve stem removal tool, etc.. IMPROPER tools include, Buck knife through the sidewall, pump pliers or vise grips to the stem.

# 2 ... The wrecker guy will get ****ed... False. If the proper tools in step # 1 are followed you can simply reair the tire off your rig, scba bottle, or on board air system. Besides about 95% of our wrecker guys are bringing roll backs anyway

# 3 ... We can't get our cribbing back out... False, refer back to step # 1 In the meantime stop and think about it. If your all done and the cribbing is real tight it sounds to me like it did its job. But if its real loose and can be easily plucked out the theroy of suspension system take up has just been proven. Remember my theroy of watching a fat lady get out of her car at the mall?. The car raises up 6 inchs. I bet that door, roof and victim you removed from the car weighs more then any fat lady.

# 4 ... It takes too much time .... False .. At the risk of being called a salesman, and refering back to step # 1, the PROPER tools are available. One man can totaly deflate all 4 tires in under 1 minute. Email me for details on these tools.

[Resc10]

Hey gang, I just wanted to throw in my 2 cents in reference to deflating the tires... I work full time at a station that has a heavy rescue, and Volunteer with a dept. that has a light duty squad. We have made it a regular practice to deflate tires. As long as the vehicle has been properly "prepped". This should include (but not limited to)step chocks, and wheel chocks, or any other cribbing necesary. At this point, a regular valve stem "tool" is used to remove the stem. The stem is then placed in a cut out in the top of the step chock for later reinflation of the tires. There has never been any "sudden movement" of the vehicle, and even if this were an issue, the stem can be removed in such a manner that slows the release of air. I guess the bottom line is go outside and play with it, you might like it. You have to train with ideas to see how they work. There is never any one "absolute" way to do something in rescue.

[PTFD21]

HI Ron - My Dept. is in MI and we use 4 step chocks inverted and used like a wedge for most MVA's. Tire deflation is accomplished by attaching a deflator tool. It screws on to the valve and relases the air. It makes our towing companies very happy because we can reinflate the tires with little effort. Our MVA kits all carry regulators to attach to an SCBA bottle and a tire inflator tool which makes this process easy. Also our new Engines are pre plumbed with an air hose on a reel.

ED C.
<a href="http://members.aol.com/PT10FD/info.htm">Unofficial Pittsfield Twp. F.D.</a>

[Resc10]

Sorry, but I would like to add two things, first, there will always be a situation where deflating the tires is a bad thing... About a year ago, I ran an incident involving two motorcycles and a mini-van. One of the victims was found entrapped beneath the van. Obviously this is not the timeto deflate the tires. We did however deflate the rear tires (victim was trapped directly beneath the front axle) once the vehicle had been cribbed. In this scnario, by cribbing in the front, and deflating the rear tires, the victim came out with the use of one air bag. The rear wheels become the center of your fulcrum. Second, Jim Greene was talking about the new "run-flat tires". Jim, this technology may sound confusing, but it is only desined for a "puncture" to the structure of the tire, that being the re-enforced portions (tread areas). As with any tire, once the valve stem has been removed, the tire will in-fact go flat at the same speed as any other tire. Manufacturers do keep that in mind. Thanks Resc10 MD

[J T Whidby]

My Department never deflates tires. I hve never been at a scene where I thought deflating the tires would be an advantage. Aprevious post stated they stablized with step crib then deflated the tires. If it was already stable why did you deflate the tires?

We are taught and teach the principle of STABILIZE IT WHERE YOU FIND IT.

Ron, As to your question where the car was on all four on a hard surface we would invert the step crib and insert it until tight. All stablizing methods must be monitored. If the inverted crib loosened we would push it in more. What would you do with the situation of deflated tire and loose cribbing? (it will happen)

J. T. Whidby
Georgia, USA

[Perry2085]

Hi Ron,
We usually place our step cribbing under the vehicle and then deflate the tires. This works good for us because when we are done all we have to do to get the cribbing back is re-inflate the tires and then the tow truck has good tires to haul it away.

Dan Ulrich
Perry2085

[Jim Greene]

I've read the above on this topic & responded 2 times. I see a lot of step chokes. In this day & age are we not seeing a lot of pickup trucks & of course the poplar Sport Utilites ? What do you do when step chokes are to little ? We build box cribes on four corners of the vehicle & use kevy jacks to snuge up the vehicle ( we DO NOT lift or lower the vehicle. ) as the 1 gentle man said above , what happen to stabilizing the vehicle were we found it. I feel that means any movement.
Also food for thought in the day of law suits , what would happen in a court of law if you were asked did you move the vehicle in any way that might have injured the patient any more ? How would you answer that question ? Be careful.
Just one firefighters thoughts.

[Dalmation90]

We make box cribs then have the State Trooper use his/her 10mm semi-wad cutter center punch to deflate the tires.
;-)

[Zmag]

Jim, you mentioned a box crib all the way around a 4x4 or SUV have you ever done the math for the amount of cribbing needed? A Dodge pickup would need 38-44 4x4's just to box crid the 2 rear corners. I just got back from the Ga. Extrication weekend and saw truck loads of cribbing in use for all kinds of situations. But, at the risk of sounding like a tool salesman, you can do a better job with just 2-3 foot 4x4's and a set of my Ground Pads. Don't take my word for it, just ask any of the 600 that were in the salvage yard.

[rmoore]

A Posting from Forum Moderator Ron Moore

I want to thank everyone who has participated in this thread. If you look at the numbers, this has been one of our most successful discussions yet.

Everyone treated each others' posts with respect and genuinely added to the value of information by adding your comments, teaching points, suggestions and further questions.

I will close this thread on 3-31. It has served its' purpose. I will start several new threads based on information presented here including the following;

1) stabilizing a high ground clearance vehicle such as a pickup or SUV

2) using step chocks upside down like a wedge

3) three chocks instead of four chocks under a vehicle

4) Understanding run flat tire technology

Look for the new threads on (of all days) April Fool's day.

If there are other side issues you want to discuss related to stabilization of a vehicle on four wheels, let me know.

Rmoore@firehouse.com

[rmoore]

A Posting From Carl Avery, Xtriktor@aol.com

First of all, until Ron completes his test, All the ideas posted here (mine and others) are BEST GUESSES, MY best guess is to Deflate AFTER cribbing up to the vehicle first, The goal of deflating tires is NOT to lower the vehicle to the cribbing, but to deactivate the suspension. As long as the tires are in
firm contact with the ground the suspension is still "active" or at least partially able to interact between the vehicle and the surface it is on.

And that by my definition is not a stabilized vehicle. By cribbing up to the vehicle, then deflating the Tires you take the suspension out of the equation.

At that point you achieve stabilization. As for the actual technique I vote for devices like the Z-Flation type devices (whether you buy form ZMAG or build your own)

[rmoore]

A Posting from Mike Schmidt, ZMAGRESCUE@aol.com

OK, Let me TRY to explain this one more time. ......... PROPERLY done, there is NO movement of a PROPERLY cribbed vehicle when you deflate. There SHOULD be a solid column of wood from the ground to the underside. The deflation, as Carl said, removes the suspension from the picture. You have exactly the same ground clearance before and after.

Using the PROPER deflation tools, re-airing
is quick and easy, and no problem for cleanup or towing.
Zmag
http://www.zmagrescue.com/
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