Firelite is a clear glass-ceramic, offering excellent fire resistance properties, designed specifically for use in fire doors and fire screens, where a clear uninsulated fire rated glass is required. We have had assessed both the 5mm thick and 9mm thick laminated version successfully up to 240 minutes fire resistance, and the 9mm is also a Class 2 safety glass to EN 12600: 2002. For critical locations defined by Approved Document N of the Building regulations i.e. where both width and height exceed 250mm, 9mm Firelite should be used. However, 5mm Firelite may also be used in critical locations provided that the smaller dimension does not exceed 250mm and the total area does not exceed 0.5 m², each measured between glazing beads.