Re: Deeper thought @Fred Flintstone
We have safety agencies in this world like UL, FM, CE etc that all regulate the appliances that are made.
Have any of you ever heard of a high or low limit switch? These prevent equipment from operating at too high or low a temperature. Have you ever seen a temperature/pressure relief valve on a water heater or boiler? Does a similar thing but also considers pressure excursions.
Those limit switches are mandated to be in such equipment by the regulatory agencies. The gas hot water heater won't open the gas valve if the pilot light is out, or will open the pressure valve if too much pressure builds up, the furnace/boiler does the same, the dryer has a thermal cutout switch etc, etc.
These switches do not require human interaction and thus are safer than some third party communication device or human telling it to shut down or close.
This is all a result of the KISS syndrome and for good reason. See link below for details