What helmets are approved by the U.S. Department of Transportation?

The standards for helmets set forth by U.S. DOT include:

• Helmets must weigh at least three pounds.
• Helmets must have an inner liner of a minimum one-inch-thick layer of polystyrene foam.
• Helmets must be secured to the rider’s head by chinstraps anchored to the helmet by rivets.
• Any extra components may not extend further than two-tenths of an inch from the helmet surface.
• Helmets must include a label indicating the manufacturer name, helmet model name, year of manufacture, and materials used in construction.
• Helmets must also bear a DOT sticker.

These standards come from Federal Motor Vehicle Safety Standards 218.