Five million masks are being distributed through schools in India’s capital, Delhi, where toxic air has prompted authorities to declare a public health emergency.
A Supreme Court mandated panel imposed several restrictions in the city and two neighbouring states, as air quality deteriorated to severe levels.
All construction has been halted for a week and fireworks have been banned. Delhi’s Chief Minister Arvind Kejriwal has called the city a “gas chamber”.
The masks are being handed out to students and their parents, and Mr Kejriwal has asked people to use them as much as possible.
The levels of tiny particulate matter that enter deep into the lungs are 533 micrograms per cubic metre in the city.