http://news.bbc.co.uk/1/hi/england/somerset/8676875.stm

Would this be a mains pressure HW tank with some sort of expansion
chamber ? Sounds nasty.

Rob

On 12 May, 20:56, robgraham wrote:
http://news.bbc.co.uk/1/hi/england/somerset/8676875.stm

Would this be a mains pressure HW tank with some sort of expansion
chamber ? * Sounds nasty.

Rob

Maybe an expansion vessel on a hot water heating system or some part
of a steam sterilisation system. The HSE will tell the media when they
get around to it.

On 12 May, 21:10, Onetap wrote:
On 12 May, 20:56, robgraham wrote:

http://news.bbc.co.uk/1/hi/england/somerset/8676875.stm

Would this be a mains pressure HW tank with some sort of expansion
chamber ? * Sounds nasty.

Rob

Maybe an expansion vessel on a hot water heating system or some part
of a steam sterilisation system. The HSE will tell the media when they
get around to it.

Many commercial heating systems operate with high temperature hot
water systems in excess of atmospheric pressure and above 100 degrees
C.
To acommodate the expansion and contraction of the fluid within the
system during heating cycles a cushion of compressed air or nitrogen
is employed. This is in effect a larger version of the ubiquitous
expansion vessel found in domestic sealed systems although domestics
operate below 100 deg C.
To enable maintenance replacement of the diaphragm within the vessel
these units often have a jointed access.
Purely a guess at this stage but I would say there is a probability of
the joint failing and/or the vessel rupturing, thus releasing
superheated hot water which would flash immediately into steam.
The system should have had safety valves for excess pressure but even
at normal working pressures the danger is present. Of course "someone"
with the necessary skills and knowledge should have been overseeing
the system but those of us who remember Flixborough know that the road
to hell is paved with good intentions.