Is PTFE tape safe?

[TiaraHelen]

I just wanted to check this small point about PTFE tape.
 
I had trouble when I started with the bulk propane that I just couldn't tighten the joint with the tank.  I used a mole wrench, but it somehow wasn't quite closing.  My Brother in law who is a plumber suggested PTFE tape.  I wrapped it round about 10 times, and it has made a brilliant seal. 
However, I haven't seen many references to this stuff on the database, even though lots of people have recorded probs with leaking joints - so, is it just a well kept secret, or are there drawbacks?
Thanks

[glassworks]

perfectly safe - its what gas guys use!...

there is a spray that you can get to show up any escaping gas.. or simply make a soapy water solution and brush it all over the joint.. even the tiniest leak will bubble up like mad..

[Dragonfire Glass]

I have it on mine........ 

[LittleHen]

My Brother in law who is a plumber suggested PTFE tape.   

PTFE - Plumbers Tape For Everything!!
Jessie 

[Les]

What they have all said
It's great stuff

xx

[Redhotsal]

I think the reasoning is that propane fittings - brass to brass -are supposed to be well engineered so that there shouldn't be a problem with leaks. If you do have a leak then there may be grit or other alien stuff in the threads. You should be able to get a good seal without PTFE.

However, I think oxygen is a different kettle of fish - you need to be really careful with pressurised oxygen - i.e. the bottles as opposed to an oxy-con. You shouldn't introduce any type of organic material into an oxygen line as it can lead to combustion. This probably includes PTFE, which may contain silicon/oil(?) (Not 100% sure, but I think that's correct). Also - the same with the leak detector fluid - yes, I too use a touch of fairy liquid in water for my propane line, but you should never use it for pressurised oxygen as detergent counts as an organic compound. You can buy a "proprietary" leak detector fluid (non organic) from larger B+Qs.

Here's a link from BOC about the use of PTFE in oxy lines.

http://www.bocindustrial.co.uk/bocindustrial/product_information/gas/oxidant_gases/oxygen.asp

Read the "Material Compatibility" paragraph. Based on this information I really would NOT use PTFE on any oxy line and I would be most inclined to avoid it on your propane line too for similar reasons. In reality you should be able to get a good seal without it and if you can't - you really need to look closely at your fittings. Hope this helps.

[Dragonfire Glass]

as it can eventually corrode the metal. 

I imagine it would take a while given the amount used and the thickness of the metal!