Every time a machine like this backs up, it usually emits a loud BEEP-BEEP-BEEP that travels a very ... [+] long distance. It doesn't have to be

One of the most popular articles 15 years ago talked about the problem of the loud BEEP-BEEP sound made by heavy equipment backing up. This sound travels for huge distances and is the bane of everybody who is anywhere near construction, which is a lot of people, a lot of the time. The reason the blog post is popular is a lot of people come looking for solutions.

The noise is there for a reason of course, a large fraction of workplace deaths are people crushed by equipment backing up. Nobody wants to make that easier to happen.

A company called Brigade came up with a solution in 2000 and patented it. Their solution was simple. Instead of a pure, penetrating beep tone, they use a broad spectrum white-noise or pink-noise pulse. That pulse is very obvious to somebody beside the truck, but it fades into the background noise very quickly and so doesn't travel to people who don't need to hear it. Brigade also says the tone can be heard better with less energy, and people are better able to determine the direction it is coming from.

Those who first mandated the beep thought it was good that it was annoying and impossible to ignore — and thus went for a distance. Because it "travels" like this, on any construction site (or near one) you are hearing them all the time. You become used to them and even start to ignore them, and that is why people still get crushed.

For various reasons, while Brigade is a reasonably successful company, their white noise alert never took over the world. We hear that accursed beeping everywhere in 2021. Perhaps they charged too much, or clung too tightly to their patents. Perhaps there was just little incentive for equipment makers to go through the hassle of getting a new alert cleared with local regulations and buying a more expensive patented alert. The only place I’ve personally heard the Brigade system is on some Amazon delivery vans. (Of course, part of the virtue of the system is I would not have heard it unless in the proximity of a vehicle using it.)

The good news is their main patent has now expired. With no patent, it would be easier for governments to start mandating that less intrusive, more effective systems be used, and forbid the sale (very soon) and use (in a couple of years) of gear with the beep-beep.

In fact, today there's an even better answer. It's now very cheap to get sensors which can detect if something is there behind you when backing up. Most cars today have ultrasonic sensors and backup cameras — and so does heavy equipment in many cases, even though it still beeps. Even better sensors designed for robocars using cameras, LIDARS or 3-D ultrasound can do this even more reliably. When they sense somebody behind the machine, they can start making a noise only then, or more simply, when there is danger, hit the brakes and alert the operator.

Forbidding the beeping heavy machine

The result would be safer workplaces and more peaceful towns. It’s a win-win, except for the companies who have to retrofit gear and put slightly more expensive sensors on it. I will give them some sympathy because they put on the beeper to comply with safety regulations, but I can’t give them a lot. But if they need a temporary subsidy to stop this bane of construction even faster, so be it. I am sure the construction crews themselves would be very happy too.

People hate this beep so much that a ballot proposition to ban it would pass in a heartbeat, I expect.

More controversial have been the efforts to force quiet electric cars to make sounds, both when backing up or cruising slowly. We already see this in some cars, like recent Teslas TSLA . The irony of course is that the Tesla is particularly good at knowing if there is anybody behind it when it’s backing up, or close to it when going forward. They could only make the sound when a pedestrian is present. (Tesla just issued a new feature to cars with this speaker, the ability to use it for a Public Address to yell at pedestrians or other drivers. We know that’s going to only be used for good purposes.)

One question is “how present?” Is the sound needed if somebody is on the sidewalk who somehow might not notice the EV coming up behind them? Most EVs still make more than enough tire noise, and they can easily be equipped with a microphone to know how much noise they are making and how much ambient noise is present. Current cars make a “choral” sound which is a bit distracting — it is meant to be noticed of course — but in many ways the sound of slightly noisy tires or a smooth engine might be a better choice, as they are well understood and recognized. I certainly hope we never let people customize the noise, or every car going by will be blasting the driver’s favorite tune and the roads will become a cacophony instead of more peaceful place. The white noise sounds that Brigade patented may be a better choice.

Whatever is done, our new technologies should always work to make the world a more peaceful place, and not a noisier one. Safety can be maintained without a lot of noise.