Photo credit: Mike B

by Daniel Fink, MD, Chair, The Quiet Coalition

Have you ever wondered why does your car’s speedometer go up to 160 miles per hour (mph)–or even 200 mph in the photo above–when your can might only be able to do 90 or 100? I have, but I never wondered quite enough to try to find out. Fortunately, this headline on the CNN webpage caught my eye, so now I know. One reason, according to a Toyota spokesperson, is that having the speedometer go all the way to 160 keeps the important 45-70 mph range right at the top of the dial, where it’s easy to see, but that requires the whole speedometer to show speeds up to 160.

A more plausible explanation, however, is that automakers want to communicate to buyers that their cars can go fast. Having 160 mph on the dial, though, encourages some drivers, especially young male drivers, to see how fast they can actually go.

And that leads to accidents and deaths, because highways are not racetracks and are not designed for high speeds, most cars become unstable at high speeds, and injuries tend to be more severe if an accident occurs.

The CNN article notes that when Joan Claybrook was administrator of the National Highway Traffic Safety Administration (1976-1981), she got regulations implemented limiting speedometer maximums to 85 mph. Those regulations were revoked during the Reagan administration.

Why am I writing about speedometers for a site dedicated to covering noise issues? Both automobile engines and personal listening devices produce energy outputs that can be measured, engines in terms of horsepower and speed, personal listening devices in terms of output sound volumes.

Personal listening devices don’t come with a meter indicating sound output, but settings are made in terms of percentage of maximum output. And that maximum output can range from 100 to as much as 125 decibels (dB).

Younger personal listening device users may listen to music, and older users may listen to books or podcasts, but both probably have to turn up the output volumes to 80 or 85 dB to be able to understand words over ambient noise.

Young people may also listen to their devices for several hours a day at high output volumes.

On the regulatory front, there used to be a federal agency charged with noise regulations including those for consumer products, but that agency, the EPA’s Office of Noise Abatement and Control, was defunded, also during the Reagan administration.

As with the speedometer regulation, that was clearly another public policy failure. Conservatives often decry regulations as “the Nanny State,” but the harsh reality is that evidence-based regulations meant to protect the public actually do work, and unregulated freedom for people to do as they wish often leads to harm. Recent examples of successful “Nanny State” policies that clearly work include mask mandates during the COVID pandemic and soda taxes to reduce the consumption of high-calorie sweetened beverages.

Regulations limiting speedometer speed listenings probably saved lives. Regulations that would limit personal listening device sound output levels would undoubtedly help prevent noise-induced hearing loss among personal listening device users.