The Bilco Co.’s Type SV Single Leaf Automatic Smoke Vents, available with a metal cover or a domed polycarbonate cover for natural daylighting, have received UL 793, “Automatically Operated Roof Vents for Smoke and Heat”, approval. The vents are designed to open automatically in the event of a fire to remove smoke, heat and gases from a burning building. This improves IAQ and visibility inside the building to allow occupants to escape and firefighters to do their job.