by The PB/5 pedestrian crossing button is an Australian icon: an accessibility device that has been adopted worldwide, and found its way into popular culture.
Controlled intersections are a by-product of modern life.
In the time before cars, horse and pedestrian traffic was largely unregulated. This would change with the industrial revolution: modern cities would become increasingly dense, the rise of automobiles in the 20th century meant traffic management became increasingly important.
Traffic signals were first trialled in London in the mid-19th century, deployed on a street near Parliament. These first signals were fully manual, controlled by a nearby policeman.
In the 20th century, these signalling system spread throughout the world, and became steadily more automated (read more about the first traffic lights, here).
Pedestrians were also initially governed by traffic lights. Dedicated crossing systems for foot traffic did not come along until the middle of the twentieth century.
The zebra crossing was another English innovation; the first was installed on High Street, Slough, in October 1951. The idea was to provide a dedicated crossing point for pedestrians, with striped road markings and lights, called ‘Belisha Beacons’ in England, to draw driver’s attention to them.
Zebra crossings were found to be effective, and quickly spread to other countries. The first in Australia was laid out in Brisbane, in November 1952.
The same year, in New York City, a more advanced pedestrian traffic system was tested.
On the corner of 44th Street and Broadway, in Times Square, illuminated signs were installed, that were controlled electronically. These incorporated a green ‘Walk’ sign, and a red ‘Don’t Walk’ sign, to tell pedestrians when to cross the road.
Vehicles were required to give way, in accordance with the signs.
The system was the brainchild of William Phillips Eno, a NYC transportation planner, and replaced an existing manual system that had been deployed in the 1930s. The electronic system was triggered by a push button, when someone wanted to cross.
The new signs proved effective and spread throughout America, then the world. In some areas the words were replaced with symbols, of people walking or standing still, or hands raised and lowered.
By the 1960s, these pedestrian crossing symbols had arrived in Australia. But a problem remained: the system was completely visual, and so unusable by someone with a sight impediment.
Bill Jolley, current head of ‘Vision Australia’, recalls the issue.
‘Crossing the road was pretty tricky. The basic idea was to listen to the flow of the cars. When you heard the cars on the road in front of you stop, then you knew it was safe to cross. But it was very noisy, so really quite treacherous.’
To alleviate this problem, through the 1960s different systems would be trialled, adding sound to the crossing cycle.
The first attempts were not successful. Prototypes alternated a bell and buzzer, which caused confusion: the sounds were far from intuitive as to which signal indicated walk, and they were so similar they were often confused with each other.
In 1976, acoustic consultant Louis A. Challis was hired by the NSW State Government, to come up with a solution.
Challis worked with a small team that included David Wood from Nielsen Design Associates, and engineer Frank Hulscher, from the Roads and Traffic Authority (RTA). Over several years, they worked up a design that would include several accessibility features.
It would come to be known as, the PB/5 pedestrian button.
The PB/5 is an upright, black oblong, with semi-circular ends. The bottom half contains a large, robust push button; this is controlled by magnets, and mechanically separated from the device’s electronics, to help them withstand millions of pushes.
The upper half shows a prominent arrow, in silver on blue; this indicates the crossing direction, and has a smaller raised arrow within it, which can be used like braille.
The device emits noise: a slow clicking sound for ‘Stop’, which escalates to a rapid ‘Tchk!-Tchk!-Tchk!’ when it is time to cross. A high pitched electronic whoop, indicates the transition from one state to the other.
The tone also has a locating element, that adjusts for ambient street noise, and so makes it easier for people to find the button. The central part of the arrow vibrates in unison with the sounds, providing a secondary location indicator.
After several years of development and testing, the PB/5 was first deployed in Sydney in 1984. The vision and hearing impaired community were positive, but its roll out was initially slow.
It was not until 1991, and after significant community lobbying, that the NSW State Government decided to deploy them widely, ordering 500 units.
As awareness of people with disabilities began to increase, the PB/5 spread to other jurisdictions. There are now few major road crossings in Australia without them.
Its effectiveness was such that the button would eventually be exported, and can be found in New Zealand, the United States, Ireland and Singapore. It’s a classic example of invisible design: a well-crafted everyday item, that people rarely pay attention to, which provides significant benefits.
And its story doesn’t quite end there.
In 2018, rising US pop singer Billie Eilish was in Australia for Laneway festival.
As Eilish was underage, her mother was touring with her. During their stop in Sydney, they went for a walk around the city.
‘My mom and I went for a walk, we were across the street from the hotel. The crosswalk was this little, like, you press it and it’s like ‘doop…doop’. And I was like: that’s hard! That’s the sound that it makes when you have to wait.’
– Billie Eilish
Eilish recorded the PB/5 on her phone, saving the file under the name ‘Grart’. She later sent it to her brother Finneas, who was her frequent musical collaborator.
Finneas liked the sound as well, and compressed it and sped it up. In this form it would provide the beat, in Eilish’s track ‘bad guy’, which appeared on her debut album the following year.
‘Bad Guy’ would become one of the biggest hits of 2019, selling around 20 million copies, and being streamed 2 billion times. The following year it won ‘Best Song’ at the Grammy’s, and was the breakthrough track for Eilish, helping establish her as one of the biggest pop stars of the era.
The redoubtable PB/5 is still widely used around Australia, and the world.
The RTA still owns and licenses the design, and the button is featured in the Powerhouse Museum’s permanent collection. In recognition of its contribution to society, and place in popular culture, its distinctive tones were inducted into the National Film and Sound Archive’s ‘Sounds of Australia’ collection, in 2026.
