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# HKMetadataKeyMaximumLightIntensity

A key that indicates the maximum intensity of light for an outdoor time sample.

```
let HKMetadataKeyMaximumLightIntensity: String
```

## Discussion

The expected value type is an [`HKQuantity`](/documentation/HealthKit/HKQuantity) expressed in [`lux()`](/documentation/HealthKit/HKUnit/lux()).

---

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