Determine whether an existing wet-chemical kitchen fire suppression system must be retrofitted to UL 300 and confirm its required inspection interval

Steps

1. Check the age/listing of the existing suppression system; systems installed before UL 300 testing became the norm (systems predating roughly the mid-1990s) commonly lack adequate nozzle coverage and agent capacity for modern high-efficiency fryers and cooking equipment
2. Trigger a retrofit review whenever cooking media changes (e.g., switching fryer oil type), cooking equipment is replaced, or equipment is repositioned under the hood — treat these as retrofit triggers pending confirmation from the installing/servicing fire protection contractor and local AHJ
3. Confirm the replacement/updated system is installed and listed to UL 300 (Fire Testing of Fire Extinguishing Systems for Protection of Restaurant Cooking Areas) per NFPA 96
4. Schedule inspection and servicing of the fire-extinguishing system (and any listed hood water-wash system) at least every 6 months by trained, qualified personnel, per NFPA 96 and NFPA 17A
5. Have the AHJ or installing contractor confirm the exact retrofit trigger conditions in writing, since this determination is contractor/AHJ-driven rather than a single universal numeric threshold