diesel fumes explosive?

I was surfing some of the wonderful sites on the internet that document the stupidity of others so that we can learn from them One of the best is

http://www.safetycenter.navy.mil

they generally do a good job figuring out which ones are fake and which ones real but this article:

http://www.safetycenter.navy.mil/photo/archive/archive_51-100/photo71.htm

Strikes me as unlikely. I was of the opinion that diesel didn't really give off much in the way of fumes and took a lot to get it burning out in the air. I have witnessed the demonstration where a guy throws lighted matches at a pail of diesel and they just flicker and go out. No explosion or burning or anything, unlike what would happen with gasoline!

(note: I am not suggesting that you go out and duplicate that, cause if you got it wrong and blew yourself up you'd be the topic of next weeks article on that website)

The NC-10 generator that they say was the cause of this is diesel powered (and in the second picture you can plainly see the label on the lid saying that it takes only diesel fuel) is the environment in the tank different? or hotter or something that would cause it to evaporate enough to catch fire after opening the lid and holding a lighter to the fumes?

I think that the action is almost unthinkably stupid, so I'm not trying to defend the supposed victim, but I find the story of it exploding unlikely to be true simply because diesel doesn't give off explosive fumes under any normal circumstances.

Please fill me in on the dangers of diesel fuel!

Thanks

there is a site called the darwin awards - or something like that - verry funny

I'm not at all certain about the fumes. I don't THINK they are terribly hazardous.

I work with diesel and gas burners a lot (NG and LP). To get the diesel to light off it must be atomized into a fine mist. When a gas burner works right it is the best kind period. When it ain't working right, eyebrows can be in jepordy! BIG booms can happen...

Here is a link to Caltech all about jet A fuel and the possibilities of fire/explosions...

TWA 800

-Bill

What is at work here is "Flash Point".

Flash point is the tempearature at which a fuel will "self-volatize" (become a gas or vapor) and ignite in the presence of a spark or flame.

Gasoline: -45 F
Petroleum diesel: 125 F
Biodiesel: 300 F

Biodiesel is hugely safer. I am surprised that this story shows diesel fuel igniting at room temperature? I gave a lecture last weekend and a guy said he had heard of people using diesel fuel to put out a fire. This is clearly something you'd have to be very careful of experimenting with.

You are right, although diesel is safer an empty tank is still full of fuel vapor. If activation temp and conditions are reached, ie like the spark of flint in this story then you get a very fast burning fire that sounds like a woop rather than a bang.

As a kid i got the chance to play on many farms and in particular some old 44galon drums that were used to store diesel. My brother and I had the belt taken to us many times for pouring a cup of diesel into these on a warmish day and throwing matches down the top...

We stopped after blowing the top off one of the drums. We must have had a near perfect fuel air ratio..... and burnt half the hair off our heads! .... Ahh to be a kid

Oh yes, diesel fumes or a fine mist of diesel is every bit as explosive as gasoline. Just takes a bit more heat to make diesel fumes.


Cheers. :buddies:

ikendu said:

What is at work here is "Flash Point".

Flash point is the tempearature at which a fuel will "self-volatize" (become a gas or vapor) and ignite in the presence of a spark or flame.

Gasoline: -45 F
Petroleum diesel: 125 F
Biodiesel: 300 F

Biodiesel is hugely safer. I am surprised that this story shows diesel fuel igniting at room temperature? I gave a lecture last weekend and a guy said he had heard of people using diesel fuel to put out a fire. This is clearly something you'd have to be very careful of experimenting with.

Click to expand...

Thank you for providing accurate info. It is the vapors that burn. Gasoline at 45 below zero is what makes it so dangerous.

I've heard that it is a common misconception that a full tank of fuel is dangerous when in fact an almost empty tank full of fuel vapors in the empty space is practically explosive. You could probably light a full fuel tanker truck and just watch it burn. Light a tanker with fumes in it and you'll blow a block up.

A while back when I used to be a "pyromaniac" :naughty: I was playing with a butane lighter refill in my room and I sprayed it upside down into a dish and got it to stay there in liquid form. Even though it was liquid, it was still evaporating very slowly and formed a "cloud" of gas over the top of my desk which was also running off the edge like a waterfall and collecting on the floor. What I did next was probably very dumb; I nearly burned the room down by clicking a spark ignitor about 24" away from the container. There was a huge "WOOFMP!" as the vapors ignited and flashed from where I had the ignitor across the desk following the gas that was running down the side to the floor where some had collected as well as back to it's source. It resulted in the carpet being melted, several peices of paper and an "air fern" plant catching on fire, and a bag full of electronic parts (LEDs, resistors) being shrink-wraped. The whole thing took less than one second and I was rushing out of the room with the burning paper and fern to the bathroom to extinguish them in the sink. I went back to make sure nothing else was on fire but the container I sprayed the butane into was still lit, the liquid butane would boil and the flame was burning ontop of layer of fuel vapors. After it burned itself out, I had a lot of cleaning to do plus the whole room smelled like smoke (an air fern smells very bad when burned).

Since I lecture on biodiesel, I've thought of a demonstration where I have a jelly jar can lid of gasoline... and set that on fire (which is what people would expect) and then try the same thing with biodiesel.

When I mentioned this at my most recent lecture (that I have thought of doing this), a guy said why not put out the jar lid of gasoline by pouring biodiesel on top of it.

I'll have to try that sometime before I plan the demo ...

So if the temperature in the tank was over 125F then it would have been vaporizing and could happen that way. Thats not out of the realms of possibility then.

I know about working on a car with a less than full tank, I've seen first hand what happens when a friend of mine burned down his garage while welding on his muffler... Oops. When I say garage, I mean his commercial garage business...

Thanks for all the info, very interesting stuff...

Gasoline is in fact VERY dangerous in vapor form (fumes).

I still don't feel anywhere NEAR as threatened by Diesel. But I know that there ARE situations where diesel could give you a bad time. Just hasn't happened to me in about 20+ years of messing with diesel burners....

Any petrol distillates are explosive when confined within an enclosed primeter...

Ever wonder why there are signs that tell you not to smoke in the Gym locker rooms?



My defense tool is more of a wow effect than an practical device...consists of a small can of AXE spray and a zippo

I since replaced the Axe with the "handy can" WD-40


Only disadvantage: takes both hands to light [operate] and that eliminates the usage of my EDC lights

Always paranoid [Hint: avatar]