SoundLog is an iPhone noise dosimeter app. It measures Laeq, Lcpeak, Laeq,8h and sound exposure in pascal-squared-hours. It gives an estimate of safe exposure time based on the measurement sample. A minuet-by-minute log of Laeq is saved and displayed.
SoundLog uses the built-in microphone at the bottom of the iPhone handset to measure sound level. The app runs in portrait and upside down orientation only so that the built-in mic can be directed at sound sources if so required. When a pair of Apple EarPods is plugged in, the mic of the EarPods will be used for measurement instead of the built-in mic.
To start a measurement, tap the mic icon at the top. To end a measurement, tap the mic icon again. The measurement is saved automatically by default.
Measurement records are listed in a table chronologically. Tapping on a record will reveal more detailed info. The "Laeq Minute Plot" can be scrolled horizontally to reveal the complete minute-by-minute history. Based on a measurement sample, the expected amount of sound exposure (Laeq,8h) can be predicted by specifying a nominal exposure time.
Users have the option to calibrate their phones (expert knowledge required). There are options for saving locations of measurements and saving data automatically. If "Auto Save Data" is turned off, users will need to tap on the "page + pen" icon (to the right of mic icon) to save data manually.
It is recommended to switch the phone to Airplane Mode while taking measurements to prevent incoming phone calls interrupting the operation (by design, incoming calls will terminate any measurement that is in progress).
National Acoustic Laboratories (NAL)
Research Division of Australian Hearing