It's the standard your fire inspector quotes — "NFPA-96" — and it governs how commercial kitchen exhaust systems are cleaned and maintained. Here's what it actually asks of you, minus the jargon.
NFPA-96 is the National Fire Protection Association's Standard for Ventilation Control and Fire Protection of Commercial Cooking Operations. Most California jurisdictions enforce it through the fire code, so for practical purposes it's the rulebook for your hood and exhaust system.
The standard expects grease to be removed down to the metal — across the hood, the filters, the entire duct run, and the rooftop fan. A cosmetic wipe of the visible hood doesn't meet it. If a section can't be reached, that's a problem the standard wants solved (see access panels).
"Hood cleaning" is shorthand. NFPA-96 covers the complete path grease travels: capture (hood + filters), transport (the duct), and discharge (the rooftop fan, plus containment so grease doesn't end up on the roof). A real cleaning addresses all three.
Every part of the duct has to be reachable for cleaning and inspection. Where a run is sealed with no access, code-compliant access panels get cut in. Without them, sections go uncleaned — and an inspector can flag the whole system.
The standard sets your cleaning interval by cooking type — monthly, quarterly, semi-annual, or annual — and expects the work to be documented. A dated certification sticker plus before/after photos is what proves you're compliant. (See our cleaning frequency guide.)
Two reasons: fire risk and consequences. Grease fires in uncleaned ducts are among the most common — and most destructive — restaurant fires. And after one, an insurer will ask for your cleaning records. Meeting NFPA-96 protects the kitchen and the claim.
General educational summary, not legal or compliance advice. Your exact obligations depend on your equipment and local authorities.