A ZWave smoke detector or ZWave carbon monoxide detector can be used with a Zwave hub or automation system to send email or text alerts in case smoke or CO is detected. The hub may also trigger additional actions such as turning off heating & air conditioning so the fan stops running, or turning on lights to help occupants get out safely.
You can choose to add a new smoke or CO detector that is strictly for smart home automation use. Or you can use a product like the ZWave FireFighter module that uses a specially tuned audio listening function to pick up the sound of a smoke or CO detector alarm and relay it to your smart home system.
Either way, we recommend the existing smoke and CO detectors are working and up to code as a stand alone life safety matter, and add smart functions that augment the primary system.