Fire alarm strobe lights flash to warn hearing-impaired people of fire emergencies. Typically flashing at a rate of 60 flashes per minute, many contain audible horn devices that warn the visually impaired. The Americans with Disabilities Act of 1990 led to the implementation of codes that govern the use of fire alarm strobe lights in public buildings.
The National Fire Protection Association (NFPA) requires that 110 cd strobes in sleeping areas be positioned on the wall no closer than 24 inches to the ceiling. When using 177 cd strobes, NFPA requires that the strobe be positioned no more than 24 inches from the ceiling. The strobe must be placed on the wall within 16 feet of the pillow on the bed.
For every 25 sleeping rooms up to 100, a place of lodging must have one fire alarm strobe equipped room. For buildings with 101 to 150 rooms, there must be five equipped rooms. Buildings with 151 to 200 sleeping rooms, six rooms must be equipped. If there are 201 to 300 sleeping rooms, seven rooms should have fire alarm strobes installed. For hotels with 501 to 1000 rooms, 2 percent of the rooms must be equipped with strobes. If there are 1000 plus rooms, there should be 20 fire alarm strobe equipped rooms plus 1 additional equipped room for each 100 over 1000.
Wall-mounted fire strobes must be placed 80 to 96 inches above the floor and at least six inches from the ceiling in all non-sleeping areas. Ceiling-mounted fire strobes should not be more than 30 feet above the floor. If the ceilings are higher than 30 feet, the strobes must be mounted on the wall.
The size of the room indicates how many strobes to install. A 20-by-20-foot room requires one 15 cd strobe. A 30-by-30-foot room requires one 30 cd or two 15 cd strobes. A 40-by-40-foot-room requires one 60 cd or two 30 cd strobe. A 50-by-50-foot-room requires one 95 cd or two 60 cd strobes. A 60-by-60-foot-room requires one 135 cd or two 95 cd strobes. This requirement increases up to a 100-by-100-foot room, which requires one 375 cd, two 240 cd or three 95 cd strobes.
NFPA requirements state that fire strobe lights must be visible no matter the orientation of the person in the room or corridor. The maximum spacing between fire strobes should not exceed 100 feet. All strobes must be located within 15 feet of the end of the corridor.
According NFPA 72, Appendix A, the recommended placement for corridor strobe lights indicates that any interruptions in a corridor indicates separate corridors. For example, an 100-foot corridor must have a fire alarm strobe at each end. A corridor that turns must have fire alarm strobes at the corner and each end because it is considered to be two separate corridors.