Rule 3323. A headgear for a rigid helmet may be replaced by an impact-resistant hat or cap that meets the requirements of R 408.13370 and R 408.13378 of this part, or other suitable device to which the helmet body is connected, if the helmet body may be lifted and adjusted to permit unobstructed vision or lowered to furnish complete protection, as required. The alternative device shall meet the requirements for sanitizing and resistance to heat and, in addition, shall meet the applicable requirements of any additional functions, such as protection against falling objects.
Mich. Admin. Code R. 408.13323