Why do we have to press the 'beg button'?

21 Apr 2020

Cities around the world are changing many of their traffic lights so there is no need for pedestrians to push buttons that might be infected by coronavirus.  They have been applying 'auto-on' so that the walk signal – our favourite little green man – comes on automatically.

Victoria Walks has been talking with the Department of Transport (DoT) to try to get broader use of auto-on at intersection traffic lights (not mid-block pedestrian crossings with lights). But it's fair to say the issues at traffic lights (or 'signals' as the engineers call them) are a lot more complex than you might think.

Why do we have to press a button anyway?

The green man is triggered by pressing what is often called a 'beg button,' because pedestrians have to push it to effectively ask to cross the road. 

This contrasts with the level of service given to drivers at intersections, who do not have to do anything to get a green light. This also means that if they get to the intersection just after the lights have turned green, they can still drive through. A pedestrian crossing the intersection in the same direction and arriving at the same time will have to stop, because the traffic signals would not recognise they were there and would not give them a green man.  They get to watch the cars who arrived at the same time or later than them drive through the intersection, while the pedestrian has to wait through a full cycle of the lights (a 'cycle' is the total of all the different signal phases, or vehicle movements through the intersection from all directions).

However, while it varies between intersections, pushing the button to call up the walk signal can increase the time given to that phase of the lights. So while you are walking, other people either walking or in vehicles may be waiting for longer than they otherwise would (although probably only for a few seconds). 

Auto-on for pedestrians can increase the time that the traffic lights take to move through a full cycle, causing unnecessary delays for other road users if there are no pedestrians crossing. Traffic lights are carefully calibrated to maximise traffic flow, so drivers in particular may be delayed slightly.  

Other reasons traffic light experts give for not using auto-on include:

  • Local residents may be annoyed by the sound of the pedestrian signals, which is an audio-signal for people who are blind or have low vision.
  • Some existing traffic signals are not set up for auto-on, so it would require a costly retrofit (traffic lights are very expensive). 
  • Some engineers argue that if the green man appears when there are no pedestrians, drivers will stop looking for pedestrians, but we have not seen any evidence to support this idea. 

Even without coronavirus, Victoria Walks believes the problems of auto-on are outweighed by the need to provide reasonable and safe access for pedestrians.  In addition to the timing issues discussed above, if a pedestrian forgets to press the button, assumes someone else has, or doesn't press it in time, they won't get a green man.  This means they will need to wait through a full cycle of the lights before they get a chance to cross. While it varies a lot, the wait is likely to be a couple of minutes – much longer than any delay to drivers from auto-on. Rather than wait, the pedestrian might instead choose to cross while the red signal is displayed, running the risk that drivers will not be alert for them and the signals may generate conflicting vehicle movements.

There is also the fact that people may have physical difficulty pushing the button. Small children, older people, people with a disability or in a mobility scooter and parents in some situations may find it difficult to reach the button, especially if it is not right next to the pram ramp.

It is important to understand that the issues at signalised pedestrian crossings are different. These traffic signals are set up specifically to help pedestrians cross the road, rather than to control traffic flow.  Standard auto-on is a difficult option for these crossings.

But what about coronavirus?

The virus doesn't change any of the issues above, but with only about half the usual traffic DoT is worried that both walkers and motorists will be more likely to disobey the lights if waiting time at traffic signals is increased by auto-on.  They are also concerned that auto-on would delay trucks taking supplies to supermarkets, hospitals and other destinations, and think the money could be better spent on other things.

DoT are encouraging people to press the buttons with their elbow rather than their hands and signposting the existing traffic lights where auto-on does apply. 

Is there anywhere we don't have to press the button?

Yes, in the Melbourne CBD (Hoddle grid) pedestrian signals operate automatically from 5.30am until after midnight each day. This aligns with the time public transport to the city is operating and has been in place for many years.

Sydney, Adelaide and Brisbane have introduced similar measures for their inner cities since the coronavirus pandemic.

Are there other options?

An alternative to auto-on is 'late introduction.' If a pedestrian presses the button after the parallel vehicle movement has begun, the green man will appear if there is enough time left in the phase.  However this does not address coronavirus, because the pedestrian would still need to press the button.

DoT is trialling new video technology that can not only identify pedestrians waiting to cross but assess numbers and provide more time to cross if necessary.  This has the potential to resolve most of the issues (even at signalised mid-block pedestrian crossings) and work better for both pedestrians and motorists.

Victoria Walks believes we need to move towards a system where beg buttons are not required, at least not in commercial or residential areas with significant numbers of pedestrians. If people on foot got the same level of service as people in cars, maybe we'd have more people walking and less traffic on the roads?

In the meantime, we will keep working with the Department to provide a better deal for people who are walking.

Image source unknown