On 13/02/2012 09:55, Sacha wrote:
On 2012-02-13 09:53:46 +0000, Jeff said:

Yes, an interesting site with a wide range.

BUT they describe their products as "Frost resistant". This is a
meaningless term unless qualified by the number of degrees of frost
they will withstand before cracking.

If you look at "Fire resistant" doors or safes, there are specific
requirements as to what temperature they will stand and for how long.
A sheet of hardboard will be fire resistant when compared to a sheet of
paper, but would you want it instead of the approved thing as a
critical fire door?

I can't say I've ever see anything but 'Frost resistant' on pots. I'll
ask our potman if I see him next time. Lives depend on fire
resistance but pots are, perhaps, not considered to need quite such
rigour!

See penultimate paragraph on left-hand side:
http://www.yorkshireflowerpots.co.uk/

Several years ago I had some 18" diameter bowls of these Yorkshire
Flowerpots. For some reason several cracked after a few years although
we'd had only mild winters, and they were in a position not exposed to
frost. I emailed YP with photos of the cracked pots and all were
replaced under the lifetime guarantee.

--

Jeff