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Hello, and welcome to the Grenfell Tower Inquiry podcast with me, Sharon Heemans.

This week, we heard evidence from the inquiries expert witnesses.

A fire safety engineer described what he saw during a fire test on the cladding panels installed on the tower.

These were some of the most shocking experiments I have ever witnessed after about 15 years

of working in these labs.

And an expert witness criticised the culture inside the building sector.

It was absolutely clear before this fire and I think you don't need expert evidence since

the fire that there was a climate of worrying standards.

Let's get started with the evidence. The inquiry started a new phase by hearing from a series

of experts in fire engineering who gave presentations on the fire safety regime.

Luke Bisby, who was a professor of fire and structures at Edinburgh University,

explained a series of tests performed on materials used at Grenfell Tower.

The inquiry has already established that the cladding panels were the primary cause

of the rapid spread of fire at Grenfell on the 14th of June 2017.

Professor Bisby's tests provide detailed information

on how both cladding and insulation react to fire.

He used new samples for the tests

and showed videos of his experiments.

The most dramatic results came from cladding panel manufacturers Arconic,

Rainabond aluminium composite material, made from two aluminium skins sandwiching a polyethylene core, known as ACMPE.

This is the cladding material that covered the whole of the exterior of the tower.

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