Guide
Inspection vs cleaning: why NFPA separates them
Operators often treat the hood sticker calendar as proof the system was cleaned. Secondary NFPA 96 explainers say the standard deliberately splits the work: an inspection cadence (how often someone measures grease) and a cleaning trigger (how much grease forces a clean). Those are different events, different reports, and sometimes different visit outcomes — especially in moderate- and low-volume kitchens. Section numbers and thresholds below are secondary summaries. Buy or cite the edition your AHJ adopted; this is not the official text and not legal advice.
Short answer
Secondary 2024-edition explainers describe Table 12.4 as an inspection schedule (solid monthly / high quarterly / moderate semiannual / low annual), not a cleaning schedule. Cleaning is required under the secondary §12.6 framing when measured grease crosses the applicable depth threshold (often summarized as ~0.002 in on hoods/filters/fans/ducts, ~0.078 in on other surfaces, ~0.125 in in fan housings). High-volume and solid-fuel kitchens usually clean at nearly every inspection; lower-volume kitchens may inspect without cleaning some cycles — still need the written inspection report and label.
Two jobs, two clocks
| Job | What it is (secondary) | What sets the timing | Typical paper trail |
|---|---|---|---|
| Inspection | Trained/qualified/certified person (acceptable to the AHJ) measures grease buildup across the exhaust path | Table 12.4 by cooking tier / fuel | Hood label + written inspection report within ~2 weeks (secondary §12.6.13 / §12.6.14) |
| Cleaning | Contaminated portions cleaned when inspection finds deposits past the applicable threshold (and “before heavily contaminated” intent) | Measured depth / contamination finding — not the calendar alone | Hood label + access-panel tags + written cleaning report within ~2 weeks (secondary §12.6.10 / §12.6.15) |
Same visit can include both. That is common on solid-fuel and high-volume lines. It is not automatic on every Table 12.4 date for every kitchen.
Inspection cadence (secondary Table 12.4)
| Cooking tier (secondary) | Inspect | Examples secondary sources list | Practical cleaning reality |
|---|---|---|---|
| Solid fuel | Monthly | Wood-fire pizza, BBQ, charcoal | Plan a clean nearly every cycle — grease + creosote load fast |
| High volume | Quarterly | 24-hour cooking, charbroil, wok | Usually clean at the same visit — paper-thin film on ducts/hoods trips easily |
| Moderate volume | Semiannual | Typical sit-down restaurants | Inspect on schedule; clean when depths trip |
| Low volume | Annual | Church, seasonal, senior / day-camp style kitchens | May pass without a clean some years — still need the written inspection file |
Misclassification is the common operator trap: a “casual” menu with a long charbroil day is often operationally high-volume for grease load. Pair with the volume planners linked below.
Cleaning trigger (secondary §12.6.1.1)
- Secondary sources: establish a deposition measurement system used at Table 12.4 inspections
- Depth-gauge comb on the surface — opinion is not the method (secondary §12.6.1.1.2 framing)
- Common secondary ladder: ~0.002 in (50 μm) hoods / grease-removal devices / fans / ducts; ~0.078 in (2000 μm) other surfaces; ~0.125 in (3175 μm) fan housings
- Secondary §12.6.2 intent: clean before surfaces become heavily contaminated — not only after a crisis
- Full detail and framing variance: grease depth thresholds guide
Field note — sticker ≠ cleaned
- Secondary §12.6.13: after an exhaust system is inspected or cleaned, an adhesive label goes on the hood (date, person, provider contact)
- A current sticker can mean “inspected and under threshold” or “cleaned” — read the written report before you celebrate
- Inspection report (secondary §12.6.14) and cleaning report (secondary §12.6.15) are separate two-week deliverables; both should disclose inaccessible / skipped areas
- Canopy wipe with a fresh sticker and no duct/fan findings is the classic incomplete file — see full-system vs canopy-only
Operator habits that hold up
- Ask every visit: inspection only, cleaning, or both?
- Require the depth reading (or comb photo) and which surface threshold applied
- File inspection report and cleaning report as separate tabs when both exist
- Budget combined visits for solid-fuel / high-volume; budget inspection-first for moderate / low
- Match scope to the full path: hood → filters → plenum → ducts → fan → containment
Common mix-ups
- “We’re on a quarterly sticker — we’re cleaned quarterly” (not always)
- Treating Table 12.4 as a fixed cleaning calendar for every kitchen
- Accepting “all good” with no inaccessible-area callouts
- Using “1/8 inch everywhere” as the only cleaning rule (fan-housing shorthand)
- Skipping the written report because the sticker looks fresh
Who it’s for / not for
- For: managers rewriting vendor SOWs; facilities leads who keep getting “we’re due” texts with no measurement; anyone reconciling a marshal notice that cites inspection vs cleaning separately
- Not for: substituting this page for the official NFPA text, inventing local amendments, or arguing depth numbers from a blog alone
Sources
- Facilitec Southwest — NFPA 96 codes reference (secondary; Table 12.4 is inspection schedule, not cleaning schedule; §12.6.1.1 thresholds; §12.6.2 clean-before-heavy; report/label sections)
- Facilitec Southwest — how often to clean (2026 guide) (secondary; inspection vs cleaning split; three-threshold table)
- Facilitec Southwest — cleaning report & service label (secondary; inspection and cleaning as separate events; §12.6.13 / .14 / .15 report rules)
- TFP1 — NFPA 96 cleaning frequency (secondary; cadence overview; measurement / bare-metal framing — verify edition)
- Hood Cleaning Schools — NFPA 96 excerpts page (secondary excerpt mirror of Table 12.4 / §12.6 language — not the official standard)
- HoodFilters — NFPA 96 excerpts (2024) (secondary; access / cleaning methodology notes used elsewhere on this site)
Next step
On the next vendor visit, ask in writing: “Inspection only, cleaning, or both?” Require the comb reading, the threshold applied, and separate reports if both jobs ran. Put the answer next to your Table 12.4 tier in the binder — then verify any disputed section against the edition your AHJ named, not this page.