When your bus is late, and you needed to be at work or school five minutes ago, it's hard not to be a little miffed. Especially when the bus pulls up well after its supposed arrival time.

As you watch the bus door open, anger swells up from the pit of your stomach, gains a layer of vehemence as it passes your heart, then catapults from your mouth in the form of an intense expletive. 

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The subject of your disdain is the bus driver, because she/he, after all, are to blame for the bus being late, and, by extension, you being even more late. 

By the time you sit down, however, the anger largely subsides. You're on the bus now, so why bother being pissed off about it being late? You wait for your stop and go on with your day. 

But for the STM employee who had to deal with your angry outburst, and the many others inflicted upon them by other riders, it isn't so easy. 

STM bus drivers are being assaulted, both verbally and physically, by Montrealers and it’s a major mental health issue. 

A study conducted by l'institut universitaire en santé mentale de montréal and the STM examined the workplace conditions of 118 STM drivers of the course of a year. 

The results were a little alarming. 

30% of all workplace accidents reported by STM bus drivers involved acts of violence perpetrated by passengers, reports Metro. 

These “acts of violence” were both verbal and physical in nature. So not only do STM bus drivers deal with verbally abusive passengers, they also have to put up with being physically hit or spit on. 

Unsurprisingly, wait-times for buses is the primary cause for violent outbursts from passengers. Due to this, the STM bus drivers are now calling for updated route-times that reflect the reality of the road, so riders aren’t left waiting for a bus that should have arrived already. 

For example, some bus routes have arrival times based on outdated speed limits. The arrival times are the same, yet the speed limit has been lowered, creating a disconnect between expectation and reality for STM riders which usually results in extreme anger. 

No worker should have to deal with a violently-charged and potentially unsafe workplace environment. But it’s not just bus drivers who should be worried about the study’s findings. 

Of the bus drivers participating in the study, 18% developed PTSD two months after the initial event of violence. A year later, 6% still suffered from PTSD. 

75% of bus drivers experienced some sort of psychological distress, though not clinically PTSD, with 42% still suffering 12 months after. 

Bus drivers need to be calm and alert. They are literally driving bus-loads of people along pot-hole-riddled roads with tons of other cars around them. A psychological disorder could cause a brief lapse in judgement or aptitude, and the results could be disastrous. 

So the next time your bus is late, maybe just take a deep breath and relax. It’s not your bus drivers fault, they’ve taken enough abuse.