Support
Getting started
- Open Decibel and tap Start on the Live tab. Grant microphone permission when prompted.
- The large readout shows the current sound-pressure level in dB SPL. Coloured zones: green (safe, < 70 dB), amber (caution, 70–85), red (hearing damage risk, > 85).
- Tap Stop to end the session. You'll be prompted to label and save it. Saved sessions appear in the History tab.
Common questions
Q: My readings disagree with another decibel app — which is right?
Different apps use different per-device offsets. Decibel ships with a community-built table targeting ±2 dB accuracy. If you have a Class 2 SLM, you can fine-tune ±5 dB in Settings (Pro+).
Q: Is Decibel accurate enough for OSHA documentation?
For personal-awareness screening, yes. For legal regulatory evidence (e.g. submitting to OSHA as proof of a workplace violation), no — iPhone microphones are not certified Class 1/Class 2 hardware. Use Decibel to document trends and back up with a certified meter where the stakes warrant it.
Q: Can I use Decibel in the background?
Yes. Decibel uses the audio background mode to keep accumulating OSHA dose across a workday with the phone in your pocket. You'll see a "Recording" indicator in the lock screen.
Q: Apple Watch readings look low.
The Watch microphone is omnidirectional and picks up wrist noise. Treat the Watch reading as a glanceable indicator; the iPhone reading is the primary measurement.
Q: I cancelled my subscription. What happens?
Pro features remain unlocked through the end of your billing period, then revert to Free.
Q: Where is my measurement data stored?
Locally, in the app's iOS sandbox using SwiftData. Nothing is uploaded. Deleting the app deletes all of it.
Q: How do I export an OSHA dose report?
Pro tier — open the Dose tab during or after a measurement session and tap "Export PDF report". The PDF is a single-page A4 document you can share via Mail, Messages, AirDrop, or any other share extension.
Contact
Email support@decibel.app. We typically reply within 1–2 business days.