Kitchen hood exhaust fan and make-up air interlock records before health inspection

Direct answer

Before a health inspection, the kitchen hood exhaust fan and make-up air interlock record should identify the food establishment, permit, hood tag, hood type, appliance line served, exhaust fan tag, make-up air unit tag, fan switch, control panel, temperature interlock, demand-control system where used, fire suppression interface, gas or appliance interlock where used, exhaust airflow basis, make-up air basis, balance report, capture and containment test, fan proving status, damper status, fault or alarm status, photo IDs, failed condition, correction, retest, witness, and final release boundary.

The record should prove function, not just installation. A hood photo does not prove exhaust fan operation. An exhaust fan running does not prove make-up air is available. A make-up air unit running does not prove the hood captures smoke, steam, heat, grease vapors, or cooking effluent. A temperature interlock does not prove every appliance interlock, balance report, fire suppression interface, and health-inspection concern is closed.

Do not invent a universal airflow, interlock sequence, temperature setpoint, fan proving delay, balance tolerance, or health-department acceptance rule. The adopted mechanical code, fuel gas code, food code, fire code, NFPA 96 basis, approved drawings, hood listing, manufacturer instructions, air balance report, commissioning procedure, health department, fire marshal, mechanical inspector, owner standard, and site safety plan control the work.

Why this record matters

Commercial kitchen inspections can be delayed by small gaps that are hard to fix during the inspection window: the hood lights work but the exhaust fan does not start, the exhaust fan starts but the make-up air damper is closed, the fan switch bypasses a temperature interlock, the gas appliance interlock is not proven, the balance report is missing, or the hood smokes at the cooking line because replacement air is fighting capture.

The purpose of the record is to show the chain from command to operation. It should let the health inspector, mechanical inspector, fire inspector, food-service owner, HVAC contractor, controls contractor, fire suppression contractor, electrician, and TAB provider see which hood was tested, which fans responded, which interlocks were proven, and what remains held.

This is different from a grease interceptor or floor-sink health-inspection packet. Those articles document plumbing evidence. This packet documents kitchen ventilation readiness: exhaust, make-up air, interlock behavior, capture evidence, balance evidence, and release limits.

Start with the accepted basis

Start by naming the documents that control the test. Use the approved mechanical drawings, hood submittal, fan schedule, air balance report, control wiring diagram, fire suppression submittal, kitchen equipment plan, appliance list, gas piping interlock detail where used, health department correction list, mechanical inspection note, and adopted code basis shown on the permit documents.

NFPA 96 is the public standard page for ventilation control and fire protection of commercial cooking operations. The ICC mechanical code chapter on exhaust systems includes commercial kitchen hoods, commercial kitchen make-up air, performance testing, and capture and containment language. The ICC fuel gas code includes appliance interlock language for commercial cooking appliances vented through exhaust hood systems. Those are important contexts, but the record should point to the adopted edition and approved project sequence.

If the project uses a listed hood, demand-control kitchen ventilation, tempered make-up air unit, direct gas appliance interlock, fire suppression microswitch, or BAS command, record the exact basis for that arrangement. Do not replace the approved sequence with a generic fan-start checklist.

Map the hood system

Identify each hood and every fan tied to it. Record hood tag, hood type, cooking appliances under the hood, exhaust fan tag, fan location, make-up air unit tag, make-up air source, supply fan, supply damper, fire suppression system, control panel, fan switch, temperature sensor, pressure switch, current sensor, VFD, BAS point, and alarm or fault point that matters to the test.

For multi-hood kitchens, separate zones. One make-up air unit may serve multiple hoods, or one exhaust fan may serve one hood section. A common note that says kitchen hood fans work is weak if no one can tell whether Hood H-1, H-2, and H-3 were individually proven.

The FDA Food Code treats ventilation hood systems in food preparation and warewashing areas as equipment that must prevent grease or condensation from dripping onto food, equipment, utensils, linens, and single-use items, and it requires adequate ventilation hood capacity. That health-inspection context makes the field mapping more than a mechanical closeout exercise.

Record exhaust fan operation

For each hood, record the exhaust fan command and proof. Useful fields include switch position, control panel status, VFD command, measured hertz or speed where available, current sensor status, fan proving point, airflow reading or TAB reference, roof fan photo, belt/direct-drive status where visible and safe, grease filter status, and exhaust discharge condition where relevant.

The ICC mechanical code states that mechanical exhaust systems must operate when air is required to be exhausted, and its commercial kitchen performance-test language requires verification of the exhaust airflow rate before final approval of the ventilation system. Use the approved test method and air balance report for the actual numbers.

If fan proof is indirect, say so. A green light, VFD run command, current switch, BAS status, roof observation, sound, airflow traverse, and balance report are different evidence types. The record should show which one controlled the release.

Record make-up air operation

Make-up air is part of the functional record. Record the make-up air unit tag, start command, damper open proof where used, supply fan proof, heating or cooling status if relevant, filter status, discharge condition, airflow or TAB reference, temperature concerns, and whether the make-up air starts and operates with the exhaust system as required by the approved basis.

The ICC mechanical code says makeup air is to be supplied during commercial kitchen exhaust operation and that mechanical makeup air systems are automatically controlled to start and operate simultaneously with the exhaust system. Washington kitchen systems guidance highlights the same practical concern: total kitchen make-up airflow from all sources should be approximately equal to total kitchen exhaust airflow, and makeup air must not reduce hood effectiveness.

Do not clear a health-inspection packet if the make-up air is only assumed. A hood can fail capture because supply air is off, a damper is closed, air is delivered into the hood cavity incorrectly, or the kitchen is under excessive negative pressure.

Interlocks need proof, not labels

Interlocks should be recorded as cause-and-effect tests. Identify the trigger, controlled device, proof point, expected response, actual response, delay where relevant, fault response, reset behavior, and witness. Typical triggers include fan switch, temperature sensor, heat under hood, make-up air proving contact, fire suppression microswitch, gas appliance interlock, BAS schedule, demand-control command, and manual override permitted by the approved sequence.

The ICC fuel gas code states that commercial cooking appliances vented by Type I or Type II kitchen exhaust hoods are interlocked with the exhaust hood system to prevent appliance operation when the hood system is not operating, with an exception where heat sensors or another approved method automatically activate the hood system when cooking operations occur. The field record should not decide which method is acceptable. It should prove the method that was approved.

A label that says interlocked is not enough. If the appliance, exhaust fan, make-up air unit, and control panel do not respond together under the approved test, write the hold.

Temperature interlock and proving

Temperature interlocks and fan proving features need their own lines because they are easy to confuse with manual fan control. Record sensor location, controller tag, setpoint basis, fan switch test, automatic start test, minimum run behavior where used, alarm or fault state, and whether the interlock is backup to manual operation or the primary approved method.

Greenheck's temperature interlock manual describes a package that automatically starts kitchen hood exhaust fans when heat is detected and keeps them running while heat is present. It also describes field testing by turning the fan switch on and off, then using cooking equipment under the hood to verify automatic fan startup. CaptiveAire's DCV manual describes make-up air interlock and proving logic, including supply and exhaust fan proving and alarms when make-up air signals are not received.

Use manufacturer values only for the installed system. Do not copy a factory default, delay, terminal label, or proving sequence from a manual unless it matches the installed equipment, approved submittal, and startup record.

Balance and capture evidence

The record should connect interlock function to airflow evidence. Attach or identify the TAB report, exhaust airflow, make-up airflow, hood label airflow where applicable, fan schedule, VFD setting, damper position, and any capture and containment test required by the authority or project documents.

The ICC mechanical code performance-test section says the test verifies exhaust airflow, make-up airflow, and proper operation, and it separately calls for capture and containment verification with appliances at operating temperatures and all make-up/outdoor/recirculated air sources operating. Salt Lake City's commercial kitchen hood guidance also calls for performance, capture, and containment testing and a balance report for inspection.

Do not use a running fan as a substitute for a balance report if the inspector expects the report. Do not use a balance report as a substitute for a functional interlock test if the issue is whether the hood starts when the equipment is used.

Health inspection evidence

Health inspection readiness usually focuses on food safety, cleanability, contamination, and equipment condition. For hood systems, the useful record shows that the hood and fans are not allowing grease, condensation, smoke, steam, heat, fumes, or odors to create a visible issue at the cooking line or above food-contact surfaces.

FDA Food Code language supports that practical view. It addresses hood system drip prevention, sufficient hood number and capacity to prevent grease or condensation on walls and ceilings, HVAC vent placement so make-up air and exhaust do not contaminate food or equipment, and mechanical ventilation where needed to keep rooms free of excessive heat, steam, condensation, vapors, odors, smoke, and fumes.

That does not make the health inspector the mechanical engineer. It means the closeout packet should translate the mechanical proof into health-inspection evidence: the right hood, the right appliances, no visible capture failure, no dripping, no blocked filters, no open interlock fault, and a clear release boundary.

Use an auditable table

Use the health department form, mechanical inspection form, TAB report, hood startup sheet, manufacturer checklist, or commissioning script first. Add a field table only where the required forms do not make hood and make-up air readiness easy to audit.

Build a photo packet

Photos should show the equipment and the operating state. Capture hood tag, appliance line, filters installed, fan switch, hood control panel, temperature controller, BAS or HMI status, exhaust fan tag, make-up air unit tag, damper actuator or end switch where visible, VFD run status, fire suppression panel or microswitch label where allowed, balance report cover, and any correction before and after.

Also capture health-facing evidence: no visible grease or condensate drip from hood components, clean filters in place, no obvious smoke rollout during approved test, no blocked supply diffusers that defeat make-up air, and no open alarm on the control panel.

Do not use unsafe roof access, energized cabinet photos, or cooking equipment operation outside the approved procedure just to improve the packet. A labeled exterior photo plus a signed startup or TAB record is often the safer proof.

Retests and failed conditions

Failed attempts should stay in the record. Keep the original trigger, expected response, actual result, fault, correction, approving person, retest method, retest result, and final release decision.

Common failures include exhaust fan not starting, make-up air unit not starting, make-up air damper not proving open, fan proving fault, temperature interlock not starting fans, fan switch wired to the wrong hood, TAB report missing, capture and containment failure, fire suppression interface not ready, gas interlock not proven, and health inspector concern about grease or condensation.

If only part of the kitchen is released, say so. Hood H-1 over the prep line may be ready while Hood H-2 over the cookline remains held for balance. A partial record should name the appliances and menu operations it does and does not release.

Before health inspection checklist

Run this check before representing kitchen hood exhaust and make-up air interlock conditions as ready for health inspection.

• Confirm hood tags, appliance line, permit scope, health inspection scope, approved drawings, hood submittal, fan schedule, and TAB report.
• Record each exhaust fan: tag, switch, command, proof, VFD or starter status, airflow or TAB reference, and photo evidence.
• Record each make-up air source: unit tag, command, damper proof, fan proof, airflow or TAB reference, discharge condition, and photo evidence.
• Test the approved interlock sequence: fan switch, temperature interlock, make-up air proving, appliance or gas interlock where used, BAS schedule, and fire suppression interface where part of the scope.
• Attach balance and capture evidence required by the project: exhaust airflow, make-up airflow, hood label reference, capture and containment test, and corrections.
• Check health-facing conditions: filters installed, no obvious grease or condensation drip, no smoke/steam rollout during approved test, no blocked supply or exhaust, no open hood control fault.
• Record failed attempts, corrections, retests, alarm resets, bypasses, disabled points, pending TAB work, pending fire suppression work, and health department comments.
• State the release boundary: ready for health inspection, held for mechanical inspection, held for fire inspection, held for TAB, partial hood release, or retest required.

Weak and strong records

Weak note: Hood fan and make-up air tested. Ready for health.

That note does not identify the hood, appliance line, exhaust fan, make-up air unit, interlock trigger, fan proof, balance report, capture result, failed conditions, photos, witnesses, or release boundary.

Stronger note: Hood H-2 serving the cookline in Suite 140 was functionally checked for health-inspection readiness under approved mechanical sheet M-401 revision 6, hood submittal H2-ACC-22, TAB report TAB-140-R2, and health department pre-opening item HD-07. Exhaust fan EF-2 and make-up air unit MAU-2 were commanded from hood control panel HCP-2 at 08:35. Fan switch started EF-2, MAU-2, and hood lights. HMI showed EF-2 run, MAU-2 run, and make-up air interlock closed. VFD photos show EF-2 at approved balance speed and MAU-2 at approved start command. TAB report pages for H-2, EF-2, and MAU-2 are attached.

Temperature interlock was tested with cooking equipment under the hood using the approved startup procedure. With the fan switch off, EF-2 and MAU-2 started automatically during the heat test and remained running until the controller cleared below the approved setpoint and minimum run condition. Fire suppression contractor confirmed the hood fire system interface was normal at panel HFS-2; no suppression discharge or impairment was performed as part of this health-inspection record. Capture observation showed no visible smoke rollout at the fry and griddle stations during the approved test. Initial test failed because MAU-2 damper end switch did not prove open. Controls contractor corrected the end-switch adjustment, retested, and attached photo H2-09. Hood H-2 released for health inspection of the cookline only. Dish area Hood H-3 remains held pending balance report.

The stronger note works because it connects the hood, fans, interlocks, balance report, health-facing observation, failed condition, correction, retest, and limited release.

Common mistakes

The first mistake is treating a fan sound as proof. Record command, proof, and the source of the proof.

The second mistake is testing exhaust without make-up air. Kitchen capture can fail when replacement air is missing or delivered poorly.

The third mistake is treating a temperature interlock as the whole sequence. Fan switch, appliance interlock, make-up air proof, fire suppression interface, and BAS schedule may be separate checks.

The fourth mistake is walking into health inspection without a TAB or balance reference when one is required by the project or inspector.

The fifth mistake is hiding failed attempts. A final pass does not erase a fan proving fault, wrong hood assignment, damper issue, or failed capture observation.

The sixth mistake is using the health-inspection packet as mechanical, fire, or food-establishment approval. The packet supports readiness only for the scope named in the release.

Questions that come up

Does the health inspector need to see the exhaust fan start? Use the local health department and inspection scope. Even if the health inspector does not witness fan startup, a clean functional record helps resolve questions about smoke, grease, condensation, and ventilation readiness.

Can a balance report replace a functional interlock test? No. A balance report supports airflow. It does not by itself prove that the hood control sequence starts exhaust and make-up air when required.

Can an interlock be tested without cooking? Use the approved startup or commissioning procedure. Some tests use fan switches, controller commands, simulated inputs, or controlled appliance operation. The record should state the method and its limits.

Should fire suppression be tested with this record? Only if the approved inspection scope requires it and qualified fire suppression personnel control the test. Otherwise record the status and boundary without implying suppression acceptance.

Who signs the record? Follow the contract and inspection plan. Signers may include HVAC contractor, TAB provider, controls contractor, electrician, fire suppression contractor, mechanical inspector, health inspector, owner, or general contractor depending on scope.

Compliance and safety limits

This field note is not a hood design, kitchen ventilation design, fire suppression design, gas appliance approval, mechanical code interpretation, fuel gas code interpretation, food code interpretation, NFPA 96 interpretation, TAB procedure, commissioning script, health department approval, mechanical inspection approval, fire inspection approval, energized-work permit, lockout/tagout procedure, or manufacturer instruction. The adopted codes, approved drawings, AHJ, health department, mechanical inspector, fire marshal, engineer, qualified contractors, manufacturer instructions, owner, and site safety plan control the work.

Do not use this checklist to bypass lockout/tagout, energized-work controls, roof access rules, grease duct access rules, fire suppression impairment procedures, gas appliance safety, fire watch requirements, cooking equipment startup limits, hood cleaning requirements, fan guard requirements, ladder safety, PPE, qualified-person requirements, or monitoring notifications. The packet preserves kitchen hood functional evidence before health inspection. It does not authorize unsafe testing or food establishment opening.

Sources checked

• NFPA, NFPA 96 Standard DevelopmentUsed for official NFPA 96 identity and commercial cooking ventilation control and fire protection context.
• ICC, 2021 International Mechanical Code Chapter 5 Exhaust SystemsUsed for commercial kitchen hood, exhaust fan, make-up air, performance test, capture and containment, and simultaneous makeup air operation context.
• ICC, 2024 International Fuel Gas Code Chapter 5 Chimneys and VentsUsed for commercial cooking appliance interlock context where appliances are vented by Type I or Type II kitchen exhaust hood systems.
• FDA, Food Code 2022Used for health-inspection context around ventilation hood drip prevention, hood capacity, HVAC vent placement, mechanical ventilation, duct/filter cleaning, and nuisance/discharge limits.
• Salt Lake City, Commercial Kitchen Hoods Design GuidanceUsed for municipal guidance examples covering commercial kitchen hood performance, capture and containment testing, shutdown devices, balance reports, and interlock documentation.
• Washington State Energy Code, IMC Kitchen SystemsUsed for kitchen exhaust, make-up air, DCKV, replacement air, appliance interlock, and air-balance context.
• CaptiveAire, Demand Control Ventilation Installation, Operation, and Maintenance ManualUsed for manufacturer context around make-up air interlock, supply and exhaust fan proving, interlock terminals, fan proving faults, and HMI alarms.
• Greenheck, Digital Temperature Interlock Installation, Operation, and Maintenance ManualUsed for manufacturer context around kitchen hood temperature interlocks, fan switch testing, automatic exhaust fan startup, minimum run behavior, and temperature sensor limits.
• OSHA, 29 CFR 1910.147 The Control of Hazardous EnergyUsed for safety-boundary context around hazardous-energy controls, lockout/tagout, testing, and reset limits.

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