Resumo:
Introduction: Noise is a major challenge for both occupational health and the environment,
with significant impacts on social and physiological aspects, compromising communication,
safety, health and quality of life. Although regulated devices are widely used to monitor noise
levels, their high cost and complexity in handling make them difficult for both informal workers
and the general population to access. As an alternative, smartphone applications have been
presented as practical and accessible tools for measuring noise levels. However, previous
studies do not demonstrate a consensus regarding the accuracy of these applications, which
limits their reliability for use in different contexts. Objective: To investigate the accuracy of
smartphone applications in measuring environmental and occupational noise, compared to a
standardized instrument. Method: A systematic review was carried out in the PubMed, Lilacs
and Medline databases, using the descriptors noise measurement, mobile applications, noise
meters and accuracy. The information from the included publications was analyzed
descriptively. Additionally, a criterion validity study was conducted on six applications,
belonging to different operating systems, in an uncontrolled environment, in comparison with
a calibrated sound level meter, the gold standard instrument. Measurements were performed on
four different brands of smartphones, totaling 12 pairs of measurements. The accuracy of the
applications was analyzed based on the differences between the measurements and the
correlation between the results obtained by the applications and the calibrated sound level
meter. Results: The systematic review identified 38 publications and included 16, which
analyzed the accuracy of 43 applications. On the iOS platform, the applications Sound Meter
Pro, SPLnFFT, Noisee and SLA Lite demonstrated accuracy in measuring environmental and
occupational noise. On the Android platform, Audio Tool, when used with an external and
calibrated microphone, was the only accurate one among those investigated. The findings also
revealed that there is no consensus among the studies that evaluated the same application. The
criterion validity study revealed that only the smartphone applications Sound Analyzer App, on
the Samsung device, and SmarterNoise, on the Xiaomi device, demonstrated good accuracy in
measuring occupational noise. Discussion: Smartphone applications are accurate in measuring
occupational and environmental noise, and this accuracy is influenced by accessories and
smartphones used. Although they do not replace standardized instruments, these applications
can be useful, accessible and low-cost tools for screening noise exposure, self-monitoring and
measuring noise in epidemiological studies.
