Buzzers for Smoke Alarm
UL-217 performance requirements of smoke alarm define the SPL needs to achieve at least 85dB@3M with a frequency no higher than 3.5KHz. People can detect sounds in a frequency range from about 20Hz ~ 20 kHz, and the most sensitive range is 2KHz ~ 5KHz, but we lose some high-frequency sensitivity as we mature. Seniors may not hear the alarm if the frequency is too high.
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The buzzer's SPL will be tested separately to confirm its performance. After installing the buzzer, the smoke alarm will be tested by a certificated lab.
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