Measures to protect public transport workers from abuse, such as having a shield around a bus driver's seat, are being explored, said Senior Minister of State for Transport Chee Hong Tat yesterday.

However, he stressed that commuters must also behave themselves and not resort to such abuse.

"No amount of physical barriers can help to protect the safety and dignity of our transport workers if the public does not subscribe to this important concept of showing respect to our public transport workers and allowing them to do their jobs (and) their duties in a safe environment," he added.

Mr Chee was speaking at an appreciation session held by SBS Transit to thank two men who had stopped an assault on one of its bus drivers.

Financial adviser Clement Tan Zhi Hao, 29, and university student Muhammad Mu'tasim Kassim, 25, were each given a certificate and a food hamper during the session at Tampines Bus Interchange.

They were among three men who had intervened in the incident on Sept 15. The third individual was not present at the session as he has not been identified.

In a Facebook post on Sept 16, SBS Transit said that a 52-year-old man had boarded service 21 along Pasir Ris Drive 6 at about 2.45pm on the day of the assault.

The man, who put on his mask only later, began hurling vulgarities at the driver and continued to do so for the duration of two bus stops.

SBS Transit said the commuter started physically abusing the driver after he stopped the bus in front of Block 210 in Pasir Ris Drive 1 to wait for the police to arrive.

That was when the three men intervened, dragging the assailant out of the bus and pinning him down until the police arrived.

SBS Transit noted in another Facebook post that the incident was one of several in the past few months where its drivers had been attacked for enforcing the mask-up rule.

It had close to 40 cases of public bus staff being assaulted this year, about half of which were mask-related. This was up from 33 cases in the whole of last year.

Singaporean Ja'afally Abdul Rahim, 52, has been charged over the Sept 15 assault. He is also accused of carrying a knife with a 6cm-long blade during the incident, which is an offence under the law.

Yesterday, Mr Chee said that while various measures to protect public transport workers from abuse are being explored, commuters must understand that it is still wrong to verbally and physically abuse them.

He also said that there are proper channels for unhappy commuters to provide feedback.

SBS Transit's acting chief executive Cheng Siak Kian said the operator's bus drivers are trained to de-escalate any situation which leads to an altercation between commuter and driver.

There are also devices on the bus, such as a communication system, to alert the SBS Transit's operations control centres of any bus drivers who are in trouble, he said.

Mr Cheng also said the driver has fully recovered from the assault and has been temporarily assigned to drive another bus service route.

SBS Transit has been helping the driver to pursue legal action against the assailant, he added.

Both Mr Tan and Mr Mu'tasim said they had intervened in the assault without fearing for their lives.

"I was thinking if it was someone like my loved one or my friends, I will do the same thing," said Mr Tan.

Mr Mu'tasim said he was happy that the bus driver did not suffer any serious injuries.

"If anything untoward happens, I believe that is only the right thing, that someone else steps up to help the person," he added.