For those curious, it will take around 27 pounds of Phenothiazine (PTZ) to successfully QUENCH the reaction, or, as some may call it, “short-stopping”. But these events usually occur in a “process vessel” that has an agitator. These tanks in CA do NOT appear to have agitators; however, they may be able to “mix” the contents to ensure the inhibitor remains well distributed in the solution. I was curious about this after examining the image below from ABC News:
Do you see all the 5-gallon buckets sitting on the ground? My bet is that those were a Quenching Agent, and the facility was trying to get things under control before calling the FD. They are all in the vicinity of the pumps, which could be used as an “injector and mixer.” So I asked Gemini+, “How much Phenothiazine (PTZ) is needed to quench 7,000 gallons of MMA?“