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bruceT
18th August 2006, 10:36 PM
Objet's experience with expanding oil containers reminded me of another hazard we all face as the weather warms up in the Southern Hemisphere.

As every furniture finisher knows, veg oil-soaked rags that are not disposed of regularly and left in piles, can heat up and start to smolder. They can even catch fire if conditions are right.

With drums of oil around as a ready fuel supply for a fire, the consequences could be catastophic.

Hang your rags on hooks, exposed to the air and dispose of them regularly:eek:

David
19th August 2006, 12:04 AM
I am not sure that hanging rags on hooks is the safest thing to do with them.
It -may- eliminate heat build up but if the rag did light up then it has a good source of air to burn hot and set something else afire quite easily.

As I have recently started building up a few used rags around the place, I am putting them in a tin bucket with a well fitting lid outside the garage door on the concrete with nothing flameable up against the tin. This way if they do start to smoulder, that is about all they can do because there will never be enough air in the tin to allow them to develop into a fire of any sort and the tin itself is extremely unlikely to get hot enough to catch anything on fire even if it was sitting on the outside of the tin.

I am using a few old towels which make excellent rags and have just been washing them out with some glycerin to use again as they are too good as rags to throw out just because they become a bit oil soaked.

objet
19th August 2006, 01:41 AM
I have been keeping my dirtier rags in a 20L sealed plastic drum. As long as the drum is sealed, the limited oxygen (and mould :p) in there should starve any fire. I hope.

Can filters spontaneously combust too? I use polyester bags...

Captain Echidna
19th August 2006, 10:19 AM
When chosing your drum, make sure the bottom is sealed. If they catch fire, you dont want the oil becoming runny and flowing towards something else flamable.

And on a vaugely related note this is why your tumble drier has a cool down feature at the end of the cycle. Otherwise things like teatowels sit there hot and the oil in them can catch fire.

I would imagine polyester bags could also catch fire. I think the issue is having oil in small quanties which can start to get hot, smoulder, react with oxygen to continue burning, get the oil around it hot, which make it all hot, which contributes to the burning. Of course in a drum there is lots of oil, but its hard to heat up and no oxygen except on the surface.

Hmm I might go and clean up my shed.

bruceT
19th August 2006, 12:01 PM
I am not sure that hanging rags on hooks is the safest thing to do with them.
It may eliminate heat build up but if the rag did light up then it has a good source of air to burn hot and set something else afire quite easily.

David, if they are hanging with good air circulation they can't build up heat and burn.

Storing them in a sealed drum isn't safe. Most drums have a plastic lid or bung which can deform or melt from the heat and let oxygen in. The best and safest is to store them in a drum of water, but cleaning up with soggy rags doesn't work too well :(

David
19th August 2006, 01:21 PM
My tin has no bung and is all metal, But, just to be on the safe side, How about putting them in a sealed can inside a drum full of water?

Lets see that catch Fire!! :D

bruceT
19th August 2006, 06:48 PM
My tin has no bung and is all metal, But, just to be on the safe side, How about putting them in a sealed can inside a drum full of water?

Lets see that catch Fire!! :D

Yep, that should do it:D

Captain Echidna
20th August 2006, 12:58 AM
although if they did catch fire in the drum of water, you could use it as a hot water service!:cool: Even cheaper than "night rate".;)

objet
20th August 2006, 02:05 AM
I just had thought of the effects of the combined bung-blowing and spontaneous combustion:

I'm on holiday for 3 weeks soon...500L of oil sitting around in 20L drums...a few rags get hot...a few bungs blow...AIEEEEE!!:eek:


Not so likely in winter but definately something I am aware of now.
Then again, the amount of water in my oil drums would probably put the fire out.:(

Captain Echidna
20th August 2006, 10:07 AM
If you filter the oil roughly first (I put mine through a t-shirt with the holes sewn up) then heat it slightly on a stove and bubble compressed air through it. I then turn off the stove and let the air go through it for a few hours, and it dries it quite well, and uses a lot less heat than heat alone.
You will be back to having a first class fire hazzard before you know it!:D