Ask HN: How to think about the safety of Home IoT devices?

I am currently working on a hobby/amateur IOT product ecosystem for my personal use but would wish to extend it to an actual product. How to think about safety of these devices? For example, while building a smart switchboard what kind of redundancies and contingencies to add-kill switch for the device malfunctioning, manual physical buttons, etc? Are there any books or other resources on safety of IOT devices? This kind of things would have been discussed in industrial automation.