Close Before You Doze
The Close Before You Doze Series: Decibel Readings

As part of the Close Before You Doze full-scale experiment on October 10, 2017, Steve Kerber, Vice President of Research and Director, FSRI took measurements in a bedroom with a sound level meter and recorded the difference between the loudness of a smoke alarm with the door open and the door closed. The data is shown in Table 1. Here is how these tests were conducted:

Table 1: Average Decibel Measurements

Status Decibels (dBA)
No Alarm 35
Alarm with Door Open 95
Alarm with Door Closed 78