Runaway truck

[axman51]

How many departments out there are required to use chocks on the rear tires? and has anyone had a truck runaway due to the non use on them?

[jsdobson]

Axman,

My department has a policy of chocking the tires of the front axle. While we have not had any incident of a vehicle running away while chocked, we have had situations where the vehicles moved on slippery conditions and not chocked.

We chock the front axle (in front and to the rear of the tire). The reasoning behind this is if the transmission is engaged while rear axle chocked, there may be enough torgue to climb over the chock. If the same scenario occured with the front axle chocked, the chock would skid againt the ground until it caught on something to anchor it.

BE SAFE
Before Everything, Stop And First Evaluate

[Ebayfreaktwo]

We always use chocks, but from one incident in particular, they don't work on large trucks. We had a Mack engine parked on a hill roll over the chock backwards, down the street, hit two parked cars, and go down a 30' embankment, nearly took out a house; and stopped a few feet short of a 20' deep spill way.
We are also at a forest fire once, on a good steep grade, we were parked behind a brand-spankin new forestry truck. The driver thought he knew how to engage the pump, but knocked it out of gear-no chock.
It rolled 10 feet smashed into our brush truck, knocking it out of gear, the wheel went straight up over the chock, indian tanks and tools went flying. Our driver jumped in a stopped it short of hitting a ranger truck. The FFS truck ran over its own booster line, and ripped it clean off the truck. Nobody was hurt, and it only left a small ding on our bumper. Their came new, left with a flat rear bumper, compartment door jammed shut, and no booster reel...

That's why you should use a chock, and make sure it's big enough for the task at hand...!

[BFD196]

We`ve never had any incidents, but we use them most of the time anyways.

[Dalmatian90]

Always chock. Ambulance in front of/behind rear wheel depending on which way is "downhill." Apparatus two chocks, one in front, one rear of a tire if more or less flat...if your noticeably on an incline, both on the downhill side on seperate wheels.

My department hasn't had incidents (that I know of...) but I have been at a mutual aid fire and witnessed one runaway pumper cleaning off the compartment doors of another before it went off the road and into a ditch 150' away. Was a very close call for the pump op of the 2nd pumper -- had about 10' between his pump panel and the guardrails on the side of the road...and the runaway pumper went down that side -- the pump op had to jump over the guard rail to escape.

[chrisredd]

In over 30 years, I've seen 2 "runaway trucks" that were not chocked. Both caused a lot of damage, but fortunately no inuries. I've seen a couple of trucks that were chocked that went from pump to road (Mysteriously ) and were stopped by the chocks, both had gas engines and the engines died. We always chock our trucks, even on a flat grade because our first priority is our own safety, so why take the chance?

[Donuts]

We use chocks on the rear axle, in the front or back of the tire depending on the grade. We never had any problems that I know of.(16yrs.) My question for everyone who has had a runaway or witnessed one is: were the parking brakes applied before the operator left the cab??? It may sound like a dumb question, but, with everything going on at the scene, its easy to forget something that small. I've forgotten to release the parking brake a once or twice, and the truck wouldn't move an inch.

[kfd232]

I haven't chocked wheels on any engines that had an airbrake system. Both departments I have been on have not had any incidents with those types of brake systems not working if engaged.
I have used them on hand brake trucks though.
If an airbrake system fails, it fails in the locked position.
One other thing to consider... I had an engine slip from pump to road on me as I was throttling the pump up... I am glad I didn't have the wheels chocked because it could have been a lot worse... The rpm's got high enough to start overriding the airbrakes (which will happen, trust me) luckily i noticed the engine starting to creep ahead a little and throttled down right away. Had the wheels been chocked I would have throttled it up really high until it jumped the chocks then it would have been off down the highway without me...

just some thoughts.

be safe brothers

[Malahat27]

Seems to be a common answer, but we chalk the rear axel of single axel vehicles (at front and rear of the tire in the Rescue and Rapid attack and the tanker) and the front of the rear tire on drivers side and rear of the tire on the passenger for the pumper. The chalks for the pumper are located one on each side of the truck, just behind the cab.

Closest we have had to "an incident" is when the drivers forget that they are still chalked and they try to drive away. Only vehicle we have with enough torque to pull over the chalk, is the tanker, '82 Western Star with 3000 gal onboard. The chalks are two 4x4's 24 inches long. Seen the same driver pull over them twice now - fortunately no injuries to date.

[bobsnyder]

Originally posted by Scott Reasor:
<STRONG>I haven't chocked wheels on any engines that had an airbrake system. Both departments I have been on have not had any incidents with those types of brake systems not working if engaged...If an airbrake system fails, it fails in the locked position.
</STRONG>

To be completely accurate about this...If the AIR SYSTEM within the airbrake system fails, it fails in the locked position. Just like hydraulic brake systems, however, airbrake systems depend upon either drum or disk brakes on each wheel. These are subject to the same adjustment and wear issues that those in non-air systems are. If these components fail, then the status of the air system doesn't matter.

This happened on our squirt a few months ago. The rear brakes had slid slowly out of alignment to the point that, when engaged on a hill at a minor incident, the truck started to run away. Fortunately, the driver was still on board and stopped it. We took it home and adjusted the rear brakes (just like you would on any other truck), tested it, and now it holds beautifully.

In short, the presence of airbrakes doesn't guarantee that you can't have a runaway.

Hope this helps.

[kfd232]

You are absolutely right about the drum/disk and adjustments. Thanks for clarifying that
one question... did you have the wheels chocked? just curious.

be safe brothers

[bobsnyder]

Originally posted by Scott Reasor:
<STRONG>You are absolutely right about the drum/disk and adjustments. Thanks for clarifying that
one question... did you have the wheels chocked? just curious.
</STRONG>

The truck WOULD have been chocked, but all that happened here was that the driver stopped, pulled the parking brake, left off the pedal, the thing took off, and he got back on the brakes. Nobody had even gotten off the truck to get a chock under a wheel at that point. After that, it was moved to the levelest point possible and chocked before anything else was done, obviously.

[Firebear230]

We chock the wheels anytime the truck is parked unless it is in the fire bay. We did have one incident when the truck lurched forward when the pump was engaged. It was chocked and even though the truck stalled right after it lurched, I'm sure the chocks kept it from going anywhere.

[apatrol]

No one has mentioned when they chock their wheels... Our SOP states chocking will be the first thing done.

How many of you put the truck in pump, help pull the first attack line, charge the line, chock the wheels and then establish a water supply....How do you do it and does it differ from SOP/SOG?

[CAMAINTENANCE]

We are required to chock the wheels of our vehicles when we leave the cab EVERYWHERE except when in the station. At present we are fortunant enough to have fairly new equipment. The vehicles that didn't come with auto slack adjusters have been retro fitted with them. For vehicles without the auto slack adjusters, it has been my experience that there is a definant lack of stopping power when the brakes are far enough out of adjustment that the park brake system will not hold the truck. That would fall back to the driver knowing his apparatus.
On the newer vehicles with air brake systems I personally do not see a need to chock wheels except for Aerials and that would be for the front axle ( providing it isn't lifted off the ground) while the device is being operated.
There are untold numbers of over the road rigs out there that don't even know what a chock is. How many of these do you hear about that ran away do to not having a wheel chocked? Many of these OTR trucks operate pumps while sitting at locations also.
Just my opinion.
Have a great day.

[fireguy60459]

Our dept. requires us to chock the rear wheels, evrytime the truck is parked outside of the station... We never had a truck runaway, but we where at a parade this september and we seen and platform/ladder rolling down the hill, and then we noticed that it had no driver... the cheif of our dept. managed to jump onto the truck and set the brake, it was about 5 feet away from hitting 2 parked engines... The driver of the ladder had for gotten to set the brake (pretty stupid if you ask me)

[mtnfyre21]

had a tanker runaway from us and in to a tree/
was not chocked.
sog for us is back man chocks rear wheeel on down hill side
2197 10-8
stay safe have fun stay healthy

[nomad1085]

my problem isn't remembering to chock the wheels. It is remembering to take the chock out before trying to drive away

[cmjones]

We have a 1969 pumper that the dept has had since 1969. The thing has little if any parking brake period. I think that it has been left on so many times then driven down the road that there isn't much there anymore. So we chock the tire all the time. We haven't had any problems with it running away thank goodness.

[firecat1524]

We had an incident here regarding a lack of wheel chock. A station had a call....pretty much BS, but they needed the tool box. Engineer goes back out to the truck to get the tool box....no truck. It had decided to park itself in the woods. Truck was damaged, so they notified the big chief. Big chief comes out, starts looking around where they said the truck was parked. The crew asks "Chief, what are you looking for?" Chief says " A crushed wheel chock." The engineer says " What is a wheel chock?" BAAAAAAAD hair day.
This incident happened on what appeared to be level ground..but evidently the truck found enough grade to get rolling fast enough to do some pretty serious damage to the cab.