A peripheral vision safety system and device expands peripheral vision of an individual without impeding forward vision. The expanded zone of peripheral vision provides a new level of safety for flaggers and other construction site members by reducing the risk of injury or death from passing vehicles, heavy equipment, and other hazards not in their direct line of sight. A peripheral vision safety device includes a detachable mounting clip for removably securing it to the brim of a safety helmet or cap or other type of head covering. A peripheral vision safety device includes multiple adjustable couplings configured for optimal positioning of the reflector.