Does being loud help people notice you?

Yes, this is related to the saying, “Loud pipes save lives…” but it talks about things a little more abstractly and includes a near ambulance collision!

Recently I came close to colliding with an ambulance.

While driving to work (because WNDERER is back in the shop with a transmission problem) recently, I encountered a situation where my motorcycle training paid off in the car. I had turned onto a block between tall, brick buildings and was blissfully heading toward a green light. The street view I could see looked very much like this (click the image for a larger view).

It was actually at about this distance from the intersection that I noticed something very odd: A large number of pedestrians were waiting to cross the street in the opposite direction I was traveling but weren’t moving. They had a solid “walk” signal, too. This is an area where people will routinely step out into the street when the signal says “don’t walk,” so for everyone at the corner to just stand there instead of crossing was unusual. No, wait. It was freaky strange.

I slowed down from normal speed but continued to approach the intersection. As I got close to entering it, I saw an ambulance coming from the right. In this overhead view, the green arrow represents me and the yellow one the ambulance.

Had I not noticed the odd pedestrain behaviour, the ambulance and I would probably have at least come dangerously close to meeting in the intersection.

How does this relate to loudness?

Ambulances have sirens and lights to be highly conspicuous when responding to emergencies. Their sirens are designed specifically so people will hear them, and the sirens tend to be directed forward as that’s where everybody who needs to get out of the way tend to be. Their lights are generally hard to miss.

I definitely couldn’t see this ambulance. There were buildings blocking it from my view, and the day was pretty brightly lit so I couldn’t see any hint of reflection of those lights either.

I also couldn’t hear the ambulance, at least not until I was almost at the corner. The buildings blocking my view also handily blocked almost all of the sound. I don’t drive a car with great sound insulation or an awesome radio, but those sorts of things would have contributed also to not being able to hear it.

What prevented the likely forced merging of my car with an ambulance responding to an emergency were skills I’ve learned while riding. Paying attention to what’s going on around me, and anticipating possible problems when I see something unusual are what helped prevent the sitaution from becoming worse.

Again, how does this relate to loudness?

A siren is purpose built to be heard, but the main reason people notice it is because it’s unusual. It’s also not a reliable method for alerting people to their presence, which is one reason emergency vehicles tend to have strobe lights as well. A key feature to both of these systems is they can be turned OFF. Having a bunch of vehicles constantly driving around flashing bright lights and making loud noises without need is distracting and disturbing to other road users.

The Hurt Report

The Hurt Report (officially known as MOTORCYCLE ACCIDENT CAUSE FACTORS AND IDENTIFICATION OF COUNTERMEASURES) is one of the best known studies of motorcycle accident factors. It says

The modified exhaust system was typical of many accident-involved
motorcycles, and also typical of many motorcycles observed during
exposure data collection. The modified exhaust is overrepresented
in these data, but not with high significance.

In other words, modified exhausts (which includes ones modified to be louder) seem to actually be more prevalent in motorcycle accidents, but not to a significant degree. The modifications do not contribute to safety.

Romanian investigation

More recently (about five years ago?) the Romainian Association for the National Development of Motorcycling published (PDF) a study in which they determined uniquivocally that noise is not helping with safety. They concluded that “sound produced by a motorcycle is not heard by the drivers of the cars in front or is heard too late to be able to influence the drivers’ decision.”

Bottom line

Loudness is not a “safety” thing. If you want a loud exhaust because you like it, OK. If you need that straight-pipe, derestricted, racing exhaust to squeeze that last bit of power out of your bike (but you’re paying attention to pipe diameter and backpressure, right?), that’s fine, too. (Just don’t get caught.) However, don’t lie to yourself and say it’s for safety.

If you’re relying on that loud noise to for others on the road to notice you, and especially if that’s your safety plan, then you’re doing it wrong.