Kitchen exhaust cleaning is the scheduled removal of grease from the entire commercial kitchen exhaust system, not just the part you can see from the cook line. A complete service covers the hood canopy and its baffle filters, the horizontal and vertical ductwork behind the wall, and the rooftop or inline exhaust fan at the end of the run. Technicians scrape and pressure wash interior duct surfaces, degrease the fan housing and blades, wipe down the canopy, and leave the system at bare metal wherever bare metal is reachable.
The reason it is a scheduled job rather than a discretionary one is NFPA 96, the National Fire Protection Association standard that governs commercial kitchen ventilation in the United States. NFPA 96 treats the exhaust system as a single fire path: grease that survives in one section feeds a fire that starts in another. That is why a partial clean is a compliance failure even when the hood looks spotless. The standard sets the interval by cooking volume and fuel type, running from monthly for high volume and solid fuel operations through quarterly, semi-annual and annual for lighter use.
Access is what separates a real exhaust cleaning from a cosmetic one. Ductwork needs access panels at every change of direction so a technician can physically reach the interior; without them, sections stay dirty and the inspection report says so. A competent provider will tell you where your access is missing rather than quietly cleaning around it.
You need this service if you operate any commercial cooking appliance that produces grease-laden vapor: restaurants, hotel and hospital kitchens, school and university dining halls, corporate cafeterias, food trucks with fixed hoods, and ghost kitchens. Your fire marshal, your insurer, and in most jurisdictions your health department all expect dated documentation showing the work was done on schedule and by whom. Photographs before and after, plus a service report naming the technician and the areas cleaned, are what turn a completed job into a passed inspection.
Compare providers by location in our directory of hood cleaners by state, or read the hood cleaning frequency guide before you request quotes.