Fire Alarms – Sounding the Alarm on Bedroom Audibility

Many older high-rise fire alarm systems do not provide adequate sound levels in bedrooms, even when alarms are clearly audible in hallways and living rooms. Testing has shown that bedroom speakers are often necessary to meet modern code requirements and effectively awaken sleeping occupants, making system evaluations and upgrades an important step in improving building safety and emergency preparedness.

Many high-rise residents assume their building’s fire alarm system will provide adequate warning during a fire, but this is often not the case. Testing has shown that many older residential buildings lack fire alarm speakers in bedrooms, resulting in sound levels that fall far below code-required thresholds needed to awaken sleeping occupants. Modern fire alarm codes require specific sound levels and low-frequency alarm tones inside sleeping areas, even with bedroom doors closed, because factors such as closed doors, air conditioners, hearing impairments, and deep sleep can significantly reduce a person’s ability to hear alarms. Real-world testing has demonstrated that corridor or living room speakers alone typically cannot provide sufficient sound levels in bedrooms. Building owners and condominium associations should proactively evaluate older fire alarm systems, particularly those without bedroom speakers, to ensure they meet current requirements and provide occupants with the earliest possible warning during an emergency. Proper fire alarm coverage is not only a matter of code compliance—it is a critical life-safety measure that helps save lives.
CONTACT US TO REQUEST ASSISTANCE

Fire Alarms – Sounding the Alarm on Bedroom Audibility

Will your high-rise building’s fire alarm system wake a sleeping person behind closed doors? Residents often assume that since their building has a fire alarm system, they will be properly notified of a fire in their building; however, this can create a false sense of security. Through extensive testing, we have found many residential buildings with fire alarm systems do not have adequate sound levels in sleeping areas because they do not have fire alarm speakers in the bedrooms.
 
The smell of smoke alone does not reliably awaken people that are sleeping; therefore, it is critical the fire alarm system can accomplish this. Residential buildings have a diverse range of people and situations. There are heavy sleepers, elderly, hearing-impaired, people who sleep with their doors closed, loud air conditioners, etc. With these factors in mind, fire alarm systems have strict code requirements for sound levels in sleeping areas as well as the type of tone to maximize effectiveness in awakening sleeping people.
 
The National Fire Protection Association (NFPA) requires sound levels of 15 dBA (decibels, A-weighted) above ambient, or 75 dBA minimum, whichever is greater, measured at the pillow level. It also requires a special low frequency tone (520 Hz, square wave) in sleeping areas, specifically designed to wake up people who are asleep. These sound levels are required even with the bedroom doors closed. When a new fire alarm system is installed, the sound levels are thoroughly tested inside the unit bedrooms with the doors closed and measured at the pillow level. The sound levels are measured initially by the installing contractor, then measured again by the Honolulu Fire Department (HFD) before approving of the system.
 
We have conducted sound level tests on various types of fire alarm systems, and the data consistently shows buildings without fire alarms in the bedrooms do not come close to reaching the required 75 dBA. One such building had bells in the corridors that reached 95 dBA in the corridors, which was loud enough to be uncomfortable; however, the sound levels in the bedrooms were so low they did not register on the meter (below 40 dBA).
 
In another building with a seemingly modern fire alarm system, there were speakers in the unit hallways directly facing the bedroom doors, but none in the bedrooms. The sound levels in the hallways reached 80 dBA; however, within the bedroom it only reached 51 dBA at the pillow level with the door closed. You might be wondering, “how much does 51 dBA fall short of the required 75 dBA?” It’s not even close. As decibels are logarithmic, 51 dBA is about 250 times less sound intensity than 75 dBA.
 
FAQ: “Do we really need that many speakers in the units?”
A speaker in the living room may seem loud enough when standing nearby; however, as demonstrated earlier, the sound levels do not penetrate bedroom doors effectively. The sound levels fall far short of requirements when the doors are closed. Our data has shown adding speakers in the bedrooms is the only way to achieve required sound levels in the bedrooms.
 
FAQ: “An AI-chatbot told me I don’t need that many speakers. Do I really?”
AI-chatbots may say the code does not require speakers in specific locations or quantities if sound levels are met. While technically true in a narrow sense, this is misleading because it ignores the practical reality that sound levels must be high enough in bedrooms and living rooms without exceeding maximum allowed levels near the speakers. Our testing has consistently shown speakers are needed in both, living rooms and bedrooms.
 
FAQ: “Can we just make the fire alarms in the hallways louder?”
Unfortunately, we cannot simply install bullhorns as loud as jet engines to blast sound straight through the doors. There are maximum sound level limitations required by code and for good reasons.
 
FAQ: “Won’t it be too loud with so many speakers?”
Adding more fire alarm speakers allows sound levels to be evenly spread throughout the area, like a public address (PA) system. Fewer speakers would require each one to be louder, which would cause more discomfort to occupants.
 
FAQ: “How loud does it need to be?”
The goal is to reach 75 dBA in the bedrooms at the pillow level. That’s about as loud as a vacuum cleaner. The system is intended to be heard clearly without being painfully loud.
 
FAQ: “We already did an upgrade, but we do not have speakers in the bedrooms. Are we OK?”
This situation often applies to systems that were installed about 15 or more years ago. It was common for speakers to be installed only in living rooms. However, we have seen that this does not meet required sound levels and the enforcement has become stricter on newer systems being installed. If your building does not have speakers in the bedrooms, it likely does not achieve adequate sound levels.
 
A fire can occur at any time in a building, even when everyone is asleep. But don’t let this keep you up at night. If your building has an older fire alarm system or does not have speakers in the bedrooms, be proactive and contact an experienced engineer to assess your system. Your engineer can help figure out what steps need to be taken to bring your system up to modern requirements. Adequate fire alarm coverage is not only about code compliance. It provides occupants with early warning of an emergency, which maximizes their time to evacuate, and ultimately saves lives!