Propane tank inside is it safe?

LP tanks can not be stored indoors. If they could, do you think that Home Depot, Tractor Supply and Lowes would spend all the extra money on those outdoor locking cages if they could just store. them indoors?

It is a fire hazard and against the law to store that tank inside your home.

NO!!! Good on ya for picking up on that. Mad Dog

Absolutely not!!

You could blow yourselves up!

The propane tank inside is a really bad idea and so is an unvented gas heater . Unvented gas heaters are now illegal in many jurisdictions. When operating normally they consume oxygen, emit CO2 and various nitrogen oxides which can aggravate asthma or asthma like symptoms ( I know personally from sitting in the living room of my mother in laws house with a ventless fireplace in fairly tight constructed home ). Operating improperly you can add CO to the mix. When I redid my kitchen I installed a gas cook top and electric ovens to mitigate these gases and also installed a 400 CFM range hood with exterior exhaust. I have had no symptoms with that setup .

That was a 500-gallon propane tank. It was being moved by a forklift while full, fell off and sprung a leak. That's a much more extreme situation.

Let me ask this, because it's closer I think to the OP's question. Is having a 20 pound propane tank inside the house more dangerous in any meaningful way than having, say, a five gallon can of gasoline? Or a 275 gallon tank of fuel oil? Or natural gas piping that might be 120 years old?

I can't say that it is.

Oh dear, @DCContrarian ! Yes, the propane tank is considerably riskier than the 275 gallon oil tank. The 5 gallon gasoline can — which also should never be stored in an occupied space — is somewhat less hazardous. The old natural gas piping, assuming it has been leak checked more recently than 120 years, is also much less of a hazard (Is there any natural gas that is 120 years old???)

Let's consider why. First, the oil tank. While an oil tank will make a nasty mess if it leaks, it will not explode even if it is heated. Those of us who run diesel equipment will happily confirm that fuel oil is surprisingly hard to ignite. Second, the gasoline can. Gasoline can and does vapourize. Unless the cap is really tight and the vents closed, the vapours which are much heavier than air) will move across whatever floor is handy and will find an ignition source. The resulting fire will be spectacular, but will not (bar exceptional circumstances) be an explosive one. If the gasoline can is exposed to fire, the gasoline will vapourize very quickly (unlike fuel oil) and contribute to the merriment, but not explode unless further confined. The propane tank, however, poses a hazard even if it is well sealed. If we assume that the valve is tightly closed and does not leak, it's fine — unless it is exposed to excessive heat, particularly even a relatively mild fire. Then you entirely dependent on the safety disc bursting and the resulting pressure release being adequate to prevent the tank rupturing, but not so great as to drop the pressure below the current temperature of the liquid propane — and that the torch from the safety disc is pointed somewhere safe. If the heat input to the propane tank is rapid enough, however, the pressure inside will continue to build and the tank wall weaken — to the point where the tank wall fails and the interior pressure drops to zero, at which point all the remaining liquid propane in the tank boils, and you get a small (relatively speaking) BLEVE — boiling liquid expanding vapour explosion. A standard small barbecue tank is more or less as powerful as a standard 250 pound bomb… and, in fact, such tanks have been used — with some simple but ingenious tweaking which I won't detail for obvious reasons — as excellent, easily available, cheap, bombs.

I'll grant that a leaking natural gas line is a real hazard, and will blow up your whole house (the whole block, if you do it right), but you really should smell it before it's a problem.