---
title: HKMetadataKeyAudioExposureDuration
framework: healthkit
role: symbol
role_heading: Global Variable
path: healthkit/hkmetadatakeyaudioexposureduration
---

# HKMetadataKeyAudioExposureDuration

The audio exposure event’s duration.

## Declaration

```swift
let HKMetadataKeyAudioExposureDuration: String
```

## Discussion

Discussion Use this key on headphone audio exposure events. It takes an HKQuantity containing the audio level measured in units of time.

## See Also

### Metadata Keys

- [HKMetadataKeyAudioExposureLevel](healthkit/hkmetadatakeyaudioexposurelevel.md)