Section 161.012-7 - Construction(a) Each light must be designed to be attached to a PFD without damaging the PFD or interfering with its performance.(b) Each light and its power source must be designed to be removed and replaced without causing damage to the PFD.(c) The storage life of the power source of a light must be twice as long as the period between the date of manufacture and the expiration date of the power source.(d) Each light, prior to activation, must be capable of preventing leakage from its container of any chemicals it contains or produces.(e) Each component of a light must be designed to remain serviceable in a marine environment for at least as long as the storage life of the light's power source.(f) No light may have a water pressure switch.(g) Each light must be designed so that when attached to a PFD, its light beam, at a minimum, is visible in an arc of 180 degrees above or in front of the wearer.(h) Each light, including its power source, must fit into a cylindrical space that is 150 mm (6 in.) long and 75 mm (3 in.) in diameter.(i) Each light, including its power source, must not weigh more than 225g (8 oz.).(j) Each light that is designed to operate while detached from a PFD must have a lanyard that can be used to connect it to the PFD. The lanyard must be at least 750 mm (30 in.) long.(k) Each light designed to operate while detached from a PFD must be capable of floating in water with its light source at or above the surface of the water.