That’s likely a CO2 alarm system by “LogiCO2”:
Products - Logico2
CO2 can asphyxiate people who breathe too much of it in, so it’s important to have that system in place in the event a machine starts leaking CO2. I’ve been to at least one gas station that had such a system (not sure why they chose to use a knockoff SpectrAlert but I suppose it technically works).