[dharmab]

That isn't the case. The majority of the states have no law and a good chunk of the others have exceptions for hearing protection. A lot of the websites online have outdated info- e.g. most websites claim CA and OH ban earplugs, when this clearly isn't the case.

[aidenn0]

The California carve-out for hearing protection states: "The plugs or molds shall be designed in a manner so as to not inhibit the wearer's ability to hear a siren or horn from an emergency vehicle or a horn from another motor vehicle."

Ohio has a carve out specifically for motorcycles; operators of vehicles cannot (I used to own an RV where the wind and road noise at freeway speeds was well above safe levels for sustained operation).