A person may be exempt from wearing a helmet while riding:

In Texas, a rider who is 21 years of age or older is not required to wear a helmet if they have completed a Motorcycle Operator Training Course that is approved by the Department of Public Safety. They may also be exempt from the statewide helmet requirement if they are covered by medical insurance. It is recommended that all motorcyclists wear safety helmets while riding, even if it is not required.
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