WALTHAM, MA - Around 10:30 A.M. on September 18th, Waltham Fire responded to a gas break at a construction site at 9 Hope Avenue, Waltham Hospital. Engine1, 4, Squad 5, Medic 1 and Ladder 2 were dispatched. A working fire was transmitted and E2 was assigned as the RIT. Firefighters spent about 2 1/2 hours checking for high gas readings throughout the construction site and hospital. Because of high gas readings in the crawl spaces, the construction site and hospital cafeteria were evacuated. Once National Grid addressed the leak, everyone returned to work.