If you use Explane to measure the sound level of a passing airplane, please point the microphone of your smartphone at the plane to get the most reliable measurement.
This tip originates from the Dutch Noise Abatement Society (Nederlandse Stichting Geluidshinder, https://nsg.nl). Thanks!
Not pointing at the airplane will likely registrate lower than real noise levels, so you will measure in favour of the aviation industry.
In rare cases we see registrations with very low noise levels, like 8 dB. Those measurements will likely originate from smartphones with a defect in the microphone or when a user has put a finger over the microphone during the measurement. You can choose to not send in such measurements by not clicking the button, and go back to the home screen of the app.