A normally-closed gas solenoid valve is a readily available item for about $200. https://www.mcmaster.com/gas-solenoid-valves/solenoid-on-off-valves-for-natura

A normally-closed gas solenoid valve is a readily available item for about $200. https://www.mcmaster.com/gas-solenoid-valves/solenoid-on-off-valves-for-natural-gas-propane-and-butane-9/ https://www.mcmaster.com/gas-solenoid-valves/solenoid-on-off... Combine with a countdown timer: https://www.intermatic.com/Catalog/us/Products/In-Wall-Controls/Spring-Wound-Countdown-Timers/FF32H https://www.intermatic.com/Catalog/us/Products/In-Wall-Contr... At ~$1200 DIY is a add-on fire suppression system for the range that would include a similar gas valve or contactor to shut down the range if fire suppression activated plus fire alarm klaxon and alarm system tie in possibilities. https://guardianssi.com/ https://guardianssi.com/