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# HMCharacteristicTypeCarbonMonoxideDetected

An indicator of abnormally high levels of carbon monoxide.

```
let HMCharacteristicTypeCarbonMonoxideDetected: String
```

## Discussion

The corresponding value is one of the constants in the [`HMCharacteristicValueCarbonMonoxideDetectionStatus`](/documentation/HomeKit/HMCharacteristicValueCarbonMonoxideDetectionStatus) enumeration.

## Topics

### Values

[`HMCharacteristicValueCarbonMonoxideDetectionStatus`](/documentation/HomeKit/HMCharacteristicValueCarbonMonoxideDetectionStatus)

Possible values for the state of carbon monoxide level detection.


---

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