Help sign saves Brisbane bus driver

Tracey Ferrier and Miriam Deprez

A Brisbane bus driver is back on the job after a terrifying ride with an erratic passenger that ended after he activated a help sign on the front of his vehicle.

The driver has undergone counselling after the agitated man boarded his empty bus in inner-city Spring Hill on Wednesday and made demands to be taken for a ride.

The driver complied but managed to press a duress button that alerted authorities and changed the sign on the front of his bus to say "Call police!".

A passer-by saw the sign and called for help at the same time as police were using GPS technology to track the bus.

Police stormed the bus and arrested the 28-year-old but had to taser him as he tried to escape by using his head to smash glass panels at the back of the vehicle.

The alleged offender was taken to hospital with cuts to his head and is expected to face drug and wilful damage charges.

The driver, aged in his 40s, was not hurt and returned to work under supervision on Friday, the Rail, Tram and Bus Union told AAP on Friday.

Union spokesman Tom Brown said the duress alarm had done its job but the union believed driver safety systems were still inadequate 18 months on from the horrific death of driver Manmeet Alisher.

Mr Alisher was set alight by a passenger who boarded his Brisbane bus in October 2016.

"Drivers get daily abuse and every time a passenger blows up at a bus driver they think, 'Is this my turn?'," Mr Brown said.

Since Mr Alisher's death, bus drivers have staged strikes over safety and other issues.

The state government last year released its interim response to a safety review sparked by Mr Alisher's death, including making duress alarms mandatory in all buses and assessing the effectiveness of existing partial driver barriers.