(a) Once engaged, the restraining device for a forward-facing seat shall not release or fail when a forward longitudinal force, rein newtons, equal to 20 times the mass of the hinged or folding portion of the seat in kilograms multiplied by 9.8 is applied through the center of gravity of https://www.webwiki.co.uk/www.ledteks.com/seatbelt-and-safety-belt-webbing