u/toooomanypuppies

The LEL (Lower Explosive Limit) for CH4 is 4.4%/vol. The UEL (Upper Explosive Limit) is 17%/vol, UK regs.

In the US, it's 5% LEL and 15% UEL, significantly different to the UK.

Now, methane, oxygen and the chemistry of explosions don't change, so which of the above is correct?

With a 2% difference in the UEL alone, one must be incorrect?

I assume I'm missing something, hoping you can explain this to me.

Thanks in advance,n

In the UK (and EU) it's 4.4%/vol for CH4, UEL is 17%/vol.

In the US, the LEL is 5% and UEL is 15%.

Why are these so drastically different? obviously, methane and oxygen don't change if you cross the Atlantic and physics is just physics, universal.

So surely, unless I'm missing something, one of these must be incorrect?