You don’t need nearly as much hearing protection for lawn mowers and motorcycles compared to someone operating a jackhammer or similarly loud equipment for hours a day.
I don't think that's entirely true. Motorcycle noise on highways can be in excess of 100 dB and is broad spectrum noise. Most highway motorcycle rides are in the tens of minutes to hours range, but the damage can occur in just the single digits to teens of minutes.
Beyond a certain point, it doesn't really matter much that something is worse for your hearing than something that will permanently damage your hearing. Plus, people are interacting with lawn equipment, motorcycles, and other such things far more frequently than jackhammers.
Jackhammer’s can be 130 decibels it’s easily a thousand times as loud as motorcycles so we really are talking different realms of sound protection being needed.
Also Motorcycle helmets should reduce things. Further it varies but motorcycles really shouldn’t be 100db, California’s legal limit is 80db for motorcycles manufactured after 1985.
At highway speed here in France, (110-130 km/hr), the wind noise is sufficient to cause tinnitus for me, if I'm not wearing ear protection under my helmet. The bike style is a factor - my touring bike has a movable windshield that can push the airflow above my head, but the wind noise from the daily bike, with a tiny windshield, is like sticking your head out the window of a moving car.
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