"Thomas Prufer" wrote in message
...
On Sat, 30 Jun 2007 21:37:46 +0100, Mike D
wrote:

My house is about 100 years old and has various old redundant gas
pipes, imbedded in the walls and under the floors, but the only pipe
which is supposed to be live is teh one going directly from the meter
to my central heating boiler. And that is all at thoe opposite end of
the house from where the slight gas smell has been commented on.

Old gas pipes can give of the smell of gas -- it's a powerful scent, and a
little goes a long way.


Thomas Prufer

Methane is odourless so they add a 'smelly'. I think the additive is Ethyl
Mercaptan (Ethanethiol) and its a ridiculously low concentration as that
stuff is so smelly. When I worked in a lab years ago, someone threw 5
millilitres down a sink and the building had to be evacuated due to the
nauseous affect of the pong. Neighbours around the site were phoning British
Gas reporting smell of gas.

Paul