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

Kate Lamble is away this week, but she'll be back next Friday.

This week, Janice Ray, the manager responsible for health and safety at the tenant management

organisation, which ran the tower,

finished her evidence. And we learnt this week, the London Fire Brigade questioned the competence

of the fire risk assessor at Grenfell three times before the fire. To try to understand why the

LFB did this, we'll start by looking at this week's evidence on the smoke ventilation system,

or AOV, installed at Grenfell. It's an issue we've heard about again and again on the podcast,

for good reason. The AOV is a fire safety mechanism designed to remove smoke from communal

areas in the event of a fire, and to keep lobbies and stairwells clear so people are able to escape.

We heard during phase one evidence that on the night of the fire, the AOV system did not

operate as intended. Lobbies in the tower staircase quickly filled with thick black smoke.

Dennis Ray was responsible for the formulation of all health and safety policy in buildings

managed by the TMO.

She appointed the consultant fire risk assessor Carl Stokes.

In April 2010, there was a fire on the lower floors of Grenfell Tower.

Although the fire didn't spread, the smoke travelled to the upper floors. The following

month, Janice Ray sent her account of the incident to the TMO and the London Fire Brigade's

fire safety team. The communal fire detection system is linked to an extraction system,

and this did operate, removing the smoke from the lift lobby. Unfortunately, it appears

that there was spillage, straight leakage of smoke from the extraction system into the lobbies of floors 712, 13, 15, 17, 18,

...