How do you protect yourself from indoor air pollution?

Air pollution is contributing to about 40,000 early deaths a year in the UK, say the Royal Colleges of Physicians and of Paediatrics and Child Health.

They say emissions from diesel engines have been poorly controlled and indoor air pollution has been overlooked.

Professor Stephen Holgate, asthma expert at Southampton University and author of the report, explained on the Today programme the simple way of mitigating against air pollution in the home.