Is it old? I think pretty much all current hobs (stove top in US English I believe) in Europe and Scandinavia have flame failure detection. It has certainly been available for decades. You can normally see a small spike sticking up that will be in the flame when it is lit. It takes a few seconds to get hot enough to hold the gas supply on, until then you have to keep the tap pushed in manually. If you let go before it gets hot enough (3 or 4 seconds) it cuts off the gas.
