If you are over 16 years old, you do not. If you are younger, you do have to wear a proper helmet. Obviously, the safety decision of not wearing a helmet is an entirely different matter and the law does not suggest that it is safe to not wear one. The helmet must be properly fitted and securely fastened on the head by a strap and the helmet must meet the standards of the American National Standards Institute, the standards of the Snell Memorial Foundation, or any other nationally recognized standards for bicycle helmets adopted by the State of Florida. Violations of this law may result in a citation and fine; however, the charge will be dismissed for a first time offense upon proof of purchase of a proper helmet.