Beijing imposed its first-ever red alert warnings for air pollution earlier this month. Schools and industries shut down, and restrictions were imposed on cars and trucks coming into the city.

But it’s not the most polluted place on the planet: the Indian capital Delhi now has that dubious distinction.

So what’s it like to live and breathe in all that smog?

The BBC’s Justin Rowlatt has been figuring that out.

Click the above audio player to hear the full report.