Bus drivers are being encouraged to wash their hair frequently and refrain from eating garlic, under new guidelines, City Evening News reported on Monday.

The guidelines, issued by Changchun Public Traffic Group northwest branch, apply to more than 500 bus drivers undergoing training.

It's the first time that a bus company publicly stated such specific requirements.

The training also includes traffic safety, vehicle service and driving.

The branch has 460 vehicles that run on 28 routes and they carry 19.8 million passengers daily.