<P> Effective January 1, 2014, section 18.4. 5.3 of the 2010 and later editions of NFPA 72 requires the low frequency audible fire alarm signal in occupancy sleeping areas with a protected premises (building) fire alarm system . The Chapter 18 committee chose to apply the requirement to all sleeping areas--not just those where occupants have self - identified as having a hearing impairment . This was done intentionally for several reasons: in many cases, the applications impacted are lodging spaces such as hotels, and many people may not know they have a hearing impairment or they may be alcohol impaired . </P> <P> The 520 Hz low frequency signal is required in sleeping areas of the following buildings: </P> <Ul> <Li> Hotels and motels </Li> <Li> College and university dormitories </Li> <Li> Retirement / assisted - living facilities without trained staff responsible for waking up patients </Li> <Li> Dwelling units within apartments and condominiums </Li> </Ul> <Li> Hotels and motels </Li>

Where does the initial fire alarm signal sound in a modern high-rise building