"shaun" wrote in message
...
SNIP

It was explained to us that it's mainly to do with the airport temporarily
disabling the smoke heads where you are working to avoid false alarms and
subsequent evacuations. Don't know how true that is.


Its true.

The same rules apply in virtually any telephone exchange equipment rule,
where they usually have sensitive fire/smoke detection systems.
In this context "hot work" also includes any form of cutting or grinding
which
generates heat and/or dust.

/john