What type of notification appliance is specifically required in sleeping areas for those who are hard of hearing?

The requirement for a low-frequency audible notification appliance in sleeping areas for individuals who are hard of hearing is important to ensure effective alerting during an emergency. Low-frequency sounds, typically in the range of 520 to 1,110 Hz, have been shown to be more effective at waking individuals from sleep compared to high-frequency sounds. This is particularly crucial in the context of alerting those who may have hearing impairments, as they may not respond adequately to typical fire alarms that emit higher frequencies.

These appliances are designed to produce a sound that is more easily perceived by those who may have trouble hearing standard alarms, allowing them to react quickly in the event of a fire or other emergency. As such, using low-frequency audible alarms in sleeping areas enhances safety and compliance with fire safety codes and standards that address the needs of residents with varying levels of hearing capability.