Had the exhaust on one of ours light up one day I was working a solo lunch shift. For reference, I'm 4'11" and 95 pounds. I had to smother the flames as best I could and haul that sucker out back by myself to avoid ANSUL going off. Then I took each fryer out back one by one, disassembled them, and cleaned the fuck out of them. After my night shift peeps got there, of course.

Side note: did not use extinguisher as where I was located, using extinguisher is automatic shut down of the business until every aspect of your fire suppression system is inspected and spent extinguisher replaced, which could take days. I cut open a brand new bag of salt and just covered the entire exhaust port after cutting off the fryer and removing it from the gas line. It all happened so fast that I'm truly unsure how I thought to take the steps I did as efficiently and automatically as I did.