---
title: HMCharacteristicTypeCarbonMonoxideDetected
framework: homekit
role: symbol
role_heading: Global Variable
path: homekit/hmcharacteristictypecarbonmonoxidedetected
---

# HMCharacteristicTypeCarbonMonoxideDetected

An indicator of abnormally high levels of carbon monoxide.

## Declaration

```swift
let HMCharacteristicTypeCarbonMonoxideDetected: String
```

## Discussion

Discussion The corresponding value is one of the constants in the HMCharacteristicValueCarbonMonoxideDetectionStatus enumeration.

## Topics

### Values

- [HMCharacteristicValueCarbonMonoxideDetectionStatus](homekit/hmcharacteristicvaluecarbonmonoxidedetectionstatus.md)

## See Also

### Air quality and smoke detection

- [HMCharacteristicTypeAirQuality](homekit/hmcharacteristictypeairquality.md)
- [HMCharacteristicTypeAirParticulateDensity](homekit/hmcharacteristictypeairparticulatedensity.md)
- [HMCharacteristicTypeAirParticulateSize](homekit/hmcharacteristictypeairparticulatesize.md)
- [HMCharacteristicTypeSmokeDetected](homekit/hmcharacteristictypesmokedetected.md)
- [HMCharacteristicTypeCarbonDioxideDetected](homekit/hmcharacteristictypecarbondioxidedetected.md)
- [HMCharacteristicTypeCarbonDioxideLevel](homekit/hmcharacteristictypecarbondioxidelevel.md)
- [HMCharacteristicTypeCarbonDioxidePeakLevel](homekit/hmcharacteristictypecarbondioxidepeaklevel.md)
- [HMCharacteristicTypeCarbonMonoxideLevel](homekit/hmcharacteristictypecarbonmonoxidelevel.md)
- [HMCharacteristicTypeCarbonMonoxidePeakLevel](homekit/hmcharacteristictypecarbonmonoxidepeaklevel.md)
- [HMCharacteristicTypeNitrogenDioxideDensity](homekit/hmcharacteristictypenitrogendioxidedensity.md)
- [HMCharacteristicTypeOzoneDensity](homekit/hmcharacteristictypeozonedensity.md)
- [HMCharacteristicTypePM10Density](homekit/hmcharacteristictypepm10density.md)
- [HMCharacteristicTypePM2_5Density](homekit/hmcharacteristictypepm2_5density.md)
- [HMCharacteristicTypeSulphurDioxideDensity](homekit/hmcharacteristictypesulphurdioxidedensity.md)
- [HMCharacteristicTypeVolatileOrganicCompoundDensity](homekit/hmcharacteristictypevolatileorganiccompounddensity.md)