China has banned pilots from smoking in the cockpit on all domestic flights.

The move comes more than 20 years after the practice was outlawed on international flights by the Civil Aviation Organisation.

Pilots and crew caught breaking the ban face a 12-month suspension for a first offence, and 36 months if they’re a repeat offender.

Lighting up in the cabin was first prohibited in October 2017, with airlines given two years to stamp out the habit in the cockpit too.

But the Civil Aviation Administration of China has issued a notice banning in-flight smoking with immediate effect, reported the China Daily.

Safety concerns were raised by the practice after an Air China pilot accidentally turned off the plane’s air conditioning mid-flight in a bid to hide that he had been vaping from the captain.

Instead of switching off a fan to stop his e-cigarette smoke filtering into the cabin, he turned the cabin air con off by mistake during flight CA106 from Hong Kong to Dalian on 10 July 2018.

The stunt resulted in insufficient oxygen levels in the cabin and caused oxygen masks to drop from the ceiling.

Crew initiated a descent to a lower altitude before it was discovered that the air con was switched off.

Experts have welcomed the ban.

“If heavy smokers among the passengers can forgo their habit during flights, there is no reason to make the crew an exception, especially since they are responsible for the safety of all on board,” Zhang Qihuai, a Beijing lawyer specialising in civil aviation, told China.org.