How often should a restaurant hood be cleaned?
The short answer: it depends on what you cook and how much. California sets how often your kitchen exhaust system has to be inspected, and cleaning is required whenever that inspection finds grease buildup. Here is how that works in practice.
By AFS Hood Cleaning · Updated September 29, 2026
The schedule is set by the type of cooking
The California Fire Code, which follows the same approach as the national NFPA 96 standard, groups kitchens by how much grease they put into the exhaust system. The heavier the cooking, the more often the system has to be checked.
| Cooking operation | Inspection interval |
|---|---|
| Solid-fuel cooking operations (wood or charcoal) | 1 month |
| High-volume operations, such as 24-hour cooking, charbroiling, or wok cooking | 3 months |
| All other cooking operations | 6 months |
| Low-volume operations, such as seasonal businesses, senior centers, or places of religious worship | 12 months |
These numbers are how often the system must be inspected. They are not an automatic cleaning schedule. If the inspection finds grease on the hood, plenum, ducts, fan, or other exhaust parts, those parts have to be cleaned. In practice, most busy restaurants end up cleaning on roughly the same schedule as their inspections, because grease is almost always there by then.
Your local fire authority can approve a different interval for a specific kitchen, and it decides how these rules are enforced. See the California code guidance on our Service Reports page for the sources.
Which group is your kitchen in?
Most restaurants know right away, but a few cases are worth spelling out:
- Solid fuel (monthly). Wood-fired pizza ovens, smokers, and charcoal grills. Solid fuel produces creosote as well as grease, which is why it has the shortest interval.
- High volume (every 3 months). Charbroilers, woks, 24-hour kitchens, and busy fryer-heavy operations such as burger, chicken, and Asian restaurants.
- Moderate volume (every 6 months). A typical full-service restaurant, cafe, or hotel kitchen that cooks every day but not around the clock.
- Low volume (once a year). Kitchens that cook only occasionally, such as churches, day camps, seasonal businesses, and senior centers.
If your menu mixes styles, the heaviest cooking under a hood usually decides the group. A cafe with one charbroiler under the same hood as its ovens should plan like a high-volume kitchen.
Signs your hood needs cleaning sooner
The schedule is a minimum. Some kitchens build up grease faster than the chart expects. Call for a cleaning if you notice:
- Grease dripping from the hood edges or filters, or pooling in the grease cups.
- Filters that look coated again within days of being washed.
- Smoke hanging in the kitchen because the fan is not pulling it out.
- Grease stains on the roof around the exhaust fan.
- A louder or shaking exhaust fan, which can mean grease on the fan blades.
What you can do between cleanings
Professional cleaning covers the parts of the system staff cannot safely reach: the plenum behind the filters, the ductwork, and the rooftop fan. Between visits, most kitchens keep grease down by washing hood filters on a regular routine, emptying grease cups, and keeping the fan area on the roof clear.
Keep your last service record where you can find it. When a fire inspector asks when the system was last cleaned, a dated record with photos is the quickest answer. After each cleaning, AFS includes a recommended next-service interval based on what the crew actually found in your system, so you are not guessing. See what the service record includes.
Sources checked September 29, 2026: 2025 California Fire Code, Chapter 6, commercial kitchen hood inspection and cleaning (ICC Digital Codes); NFPA 96, Standard for Ventilation Control and Fire Protection of Commercial Cooking Operations, 2024 edition (NFPA). Your local fire authority has the final say on the requirements for your kitchen.
Common questions
Only for kitchens that cook with solid fuel, such as wood or charcoal. The California Fire Code sets a one-month inspection interval for those systems, and cleaning is required when the inspection finds grease buildup.
High-volume kitchens, such as 24-hour operations and kitchens that charbroil or cook with woks, have a three-month inspection interval. Cleaning is required whenever that inspection finds grease buildup, which for these kitchens is common.
The fire code sets the starting intervals, and your local fire authority decides how they apply to your kitchen. It can approve a different interval for a specific facility.
More hood cleaning guides
Need your hood cleaned?
AFS cleans commercial kitchen exhaust systems across the Sacramento area, with Bay Area service by schedule. Call or request a quote.