Welcome to the briefing room with me, David Oronovich. You and I step into a virtual room crammed with reference books, charts and maps, and get clear answers to today's burning questions from the experts who know what they're talking about. Now, whether we bring enlightenment or just cause confusion, please let us know what you think by writing a review or rating us on iTunes or your

podcast provider. Recent reviewers include Alex Milliner, Safia Butterfly and Pussy Lucy. Join

them and I'll read out your handle too. This week we're asking, how bad is the air we're

breathing and how can we make it cleaner?

And if you enjoy this podcast,

you might want to download other editions of the briefing room in recent podcasts.

We've covered Turkey's economy, chaos on the railways and nationalisation.

A few weeks ago, a large group of the nation's mayors and local leaders signed a letter

calling for urgent action on air pollution.

So here, inside the briefing room today, I'm going to find out how big a problem this really

is and what the potential solutions might be.

But first, because air pollution tends to be an outside thing,

let's take to the streets.

Well, to try and find out how good or bad the air is here in London, I've stepped outside. We're

actually in London Bridge, underneath the shard near to the station.

Where I'm joined by Andrew Greve, he's senior air quality analyst with the environmental research group at King's College London.

Andrew, you're a big student of air quality and you've got your phone out. What have you got there?

This is like a live map showing us pollution across the city.

So where we're standing here, you can see obviously the junction just down the street and London Bridge area around there.

You can pick out the road network where the pollution is higher.

I mean, at the moment you can feel this breeze and so it's quite good.

What is quite good mean?

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