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# HMCharacteristicTypeSecuritySystemAlarmType

The alarm trigger state.

```
let HMCharacteristicTypeSecuritySystemAlarmType: String
```

## Discussion

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

## Topics

### Values

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

Possible trigger states for an alarm.


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