In article , Neil Williams wrote:
Indeed. I watched a documentary some time ago on the issue, which
suggested[1] that, had a different type of fire-resistant lagging
been used on the "core" supports, the buildings would probably
have survived.

It does show up a potential weakness in our Building Regulations in
that you would design a building of any note to be capable of
withstanding accidental impact and also to have the requisite fire
resistance, not the two considered together. The latter is tested by
putting a protected steel beam (or whatever) in a test furnace in the
undamaged condition: if you took the average test specimen and hit it
a few times with a club hammer before testing many of the rigid board
type fire protection systems would probably not then pass.

--
Tony Bryer