Glass Times editor Nathan Bushell considers the latest news to emerge from the investigations into the Grenfell Tower fire.

Doors for flats in Grenfell Tower could only hold back a fire for half the time they were designed to, a police investigation has found.

That was the opening paragraph on the BBC news site, a site read by millions in the UK, and which was repeated on news bulletins throughout the day last Thursday (March 15, 2018).

According to experts, a door was supposed to resist fire for 30 minutes, but only lasted 15 minutes in tests.

The company that made the doors is no longer in business, but its doors are still in buildings across the UK, and the damage to the reputation of other fire door companies could be huge, especially if people stop seeing the value on legitimate fire tests.

Sean Parnaby of West Port said it was common for manufacturers to fire test their door components separately, rather than testing the completely assembled door set.

“That can lead to products with FD30 ratings that only last a fraction of the time they’re supposed to,” he said. “At West Port, we’ve come across manufacturers offering FD30 fire doors that fail in under 15 minutes, which is simply unacceptable.”

He said that every door component must be tested as part of a complete door set.

“And the 30 minutes in FD30 has to be seen as a bare minimum, not a target,” he said. “In a fire, seconds count – and that means every manufacturer has a moral responsibility to make their fire door products as good as they can possibly be.”

Simon Beer, managing director of Bluesky Certification, said it was easy for a fire door to fail if it is manufactured, installed or maintained incorrectly.

“During a fire door training day recently held by Bluesky Certification at Cambridge Fire Research, more than 20 delegates witnessed a fire test which demonstrated exactly what is likely to happen if a fire doorset has been incorrectly manufactured or installed,” he said.

“The timber doorset being tested during the training day wasn’t expected to pass. To demonstrate early failure, it had some components purposely fitted incorrectly. This included the intumescent specification fitted between the bead and the glass, the fixings used to hold the beads in place, and the timber used for the lippings around the door leaf. Despite only seemingly minor changes being made to the doorset, failure occurred at only 15 minutes.

“Many people involved in manufacturing, fitting or maintaining fire doors have never witnessed a fire resistance test, but seeing it drives home the importance fire doors play in passive fire protection. While the demonstration door didn’t achieve 30 minutes, once the test was completed and the door had cooled down, it was impressive to see how well the correctly manufactured parts of the door had resisted the intensity of the fire. Especially when you consider that the fire resistance test is based on the fire’s flashover point, meaning that the fire door is subjected to temperatures of around 1,000ºC during the test.”

I’d be interested to hear other opinions of manufacturers and installers of fire doors, especially since door companies have reported increased sales in fire doors over the last few years.