How to Clean Restaurant Hoods Safely, From Filters to Ducts

What You’ll Need to Clean a Greasy Restaurant Hood Filter?

For routine filter and hood cleaning, gather equipment that handles grease without scratching metal or spreading contaminated water around the kitchen. Read every product label before mixing or applying a degreaser.

• Personal protective equipment: chemical-resistant gloves, splash goggles, a waterproof apron, non-slip footwear, and suitable work clothing.
• Cleaning tools: plastic scraper, nylon brush, non-abrasive scrub pad, microfiber cloths, bucket, sink or soaking tub, and a wet vacuum if available.
• Cleaning products: commercial kitchen degreaser, warm water, and a clean-water rinse supply. Use a product approved for the surfaces you are cleaning.
• Protection supplies: plastic sheeting, absorbent towels, warning signs, a metal grease container, and replacement filters or gaskets if needed.

Keep food, utensils, and packaging away from the work area. For wider kitchen hygiene, the standard cutting board color chart for kitchen safety can help staff keep food-contact equipment separated during cleaning tasks.

How Often Should Restaurant Hood Filters and Hoods Be Cleaned?

Clean filters whenever grease is visible, airflow drops, or the filter feels sticky after cooling. In a busy restaurant, that often means weekly filter cleaning, while the complete hood and exhaust system follows a separate schedule.

• Solid-fuel cooking: inspect frequently and plan for at least monthly full-system cleaning where NFPA 96 applies.
• High-volume cooking: arrange full-system cleaning at least every 3 months when the kitchen runs continuously, uses woks, or produces heavy grease.
• Moderate-volume cooking: a common baseline is every 6 months.
• Low-volume or seasonal cooking: a common baseline is every 12 months, provided inspections show limited grease buildup.

These intervals reflect the NFPA 96 cleaning framework as checked in September 2026, not a universal legal schedule. Your fire marshal, insurer, health department, or adopted local code may require shorter intervals.

What Safety Precautions Should You Take Before Cleaning a Commercial Hood?

Make the kitchen safe before applying water or chemicals: stop cooking, isolate energy sources, protect nearby equipment, and prevent cleaning residues from contacting food surfaces. Do not work alone on high areas or around electrical components.

• Schedule cleaning after service, when burners, fryers, lights, and metal surfaces are completely cool.
• Turn off cooking equipment and isolate gas and electrical supplies according to the equipment manufacturer’s procedure.
• Cover appliances, prep surfaces, and exposed food-contact areas with plastic sheeting and towels.
• Place warning signs for wet floors, maintain ventilation, and follow the degreaser’s dilution and contact-time instructions.
• Never mix degreaser with bleach, ammonia, acids, or another cleaning chemical. Chemical reactions can release dangerous vapors.
• Use a stable platform or approved ladder, and stop if you cannot reach a surface without stretching.

OSHA recommends using hazard communication information, including Safety Data Sheets, for workplace chemicals. If a product splashes into your eyes or onto skin, follow its first-aid instructions and seek medical help when directed.

How to Clean a Greasy Range Hood Filter Step by Step?

Use this process for removable commercial filters and accessible hood surfaces. It is suitable for routine maintenance, not for opening or dismantling the exhaust fan, ductwork, or roof discharge assembly.

1. Turn Off and Cool the Cooking Equipment

Switch off burners, fryers, heat lamps, and hood controls, then wait until surfaces are cool enough to touch safely. If the manufacturer’s instructions require a particular isolation procedure, follow those instructions instead of relying only on the control switches.

Check that no food preparation is taking place beneath the hood. Cover or remove nearby equipment before wet cleaning begins.

2. Remove the Hood Filters Carefully

Support each filter with both hands while removing it, because saturated grease can make the metal slippery and heavy. Remove grease cups or trays as well, and empty them into a metal container.

Inspect the retaining clips, filter frame, and gaskets as you work. Bent filters or missing seals can allow grease to enter the ductwork even after cleaning.

3. Scrape Off Heavy Grease Buildup

Use a plastic scraper to lift thick deposits into the waste container before soaking. Avoid knives, screwdrivers, and wire brushes, which can gouge stainless steel or damage filter mesh.

Do not flush collected grease down a sink. It can harden in plumbing and create a blockage, so dispose of it through your commercial waste procedure.

4. Soak the Filters in Degreaser

Fill a suitable sink or tub with hot water and add the commercial degreaser at the label’s stated dilution. Submerge compatible filters fully and keep the area ventilated.

Allow the labelled contact time, often between 15 minutes and 2 hours depending on the product and grease load. Do not assume overnight soaking is safe, especially for aluminum or coated components, because strong chemicals can discolor or corrode them.

5. Scrub, Rinse, and Dry the Filters

Scrub in the direction of the metal grain with a nylon brush or non-abrasive pad. Work around corners, baffle channels, handles, and drain holes where grease commonly remains.

Rinse with clean water until no foam or slippery residue remains, then inspect against a bright light. Dry the filters completely with clean towels or allow them to air-dry before reinstalling them.

6. Clean the Hood Interior and Exterior

Apply diluted degreaser to a cloth or pad rather than spraying directly around lights, switches, seams, or electrical fittings. Wipe the interior canopy from the cleanest areas toward the dirtiest, then rinse with a damp clean cloth.

Clean the exterior, seams, handles, and grease channels, then dry all surfaces. If grease remains inside a duct entrance or around the fan opening, stop and arrange professional service rather than reaching into the system.

7. Reinstall the Filters and Check Airflow

Replace each dry filter in its original direction and confirm that it sits tightly in the retaining channels. Refit grease cups and trays, then remove protective sheeting without dragging dirty water over food-contact surfaces.

Restore power according to the equipment procedure and check that the hood operates normally. Weak suction, unusual vibration, persistent smoke, or grease dripping from the duct connection indicates a service problem.

How Do You Clean Different Types of Restaurant Hood Filters?

Filter material determines the safest cleaning method. Check the hood manufacturer’s care instructions before using hot water, alkaline degreaser, a dishwasher, or pressure washing.

Stainless Steel Baffle Filters

Stainless steel baffle filters usually tolerate hot water and a compatible commercial degreaser. Scrub along the grain, rinse thoroughly, and dry them to reduce water spots and corrosion around fasteners.

Do not use chlorine bleach or steel wool on stainless steel. These can damage the surface and leave particles that later rust.

Mesh Filters

Mesh filters need gentle brushing because flattened layers can restrict airflow. Soak them only as long as the product label permits, then rinse from the clean side outward so loosened grease leaves the mesh.

Replace a mesh filter if its layers are crushed, permanently clogged, or separating. A filter that cannot be cleaned open is not protecting the duct system effectively.

Aluminum Filters

Aluminum filters are vulnerable to strong alkaline cleaners, excessive heat, and prolonged soaking. Use a product specifically labelled as safe for aluminum, follow its dilution exactly, and rinse promptly.

Replace aluminum components that become badly discolored, brittle, warped, or corroded. Do not put them in a dishwasher unless the manufacturer explicitly approves that method.

How Do You Clean the Hood Fan, Ducts, and Exhaust System?

The fan, ducts, grease containment areas, and roof or wall exhaust outlet need a complete inspection and cleaning by a qualified commercial hood service. These parts may contain hidden grease, require access panels, and can expose workers to electrical, fall, and fire hazards.

A professional service should protect cooking equipment, remove grease from the accessible interior of the entire exhaust path, clean the exhaust fan and housing, inspect access doors, and leave the system dry. Ask for before-and-after photographs when access is limited, plus a dated certificate describing the areas serviced.

The National Fire Protection Association’s NFPA 96 standard is widely used for commercial cooking ventilation, but the adopted local fire code controls enforcement. Never pressure-wash an exhaust system casually, because contaminated runoff can enter electrical parts, roofing, drains, or food-preparation areas.

What Should You Not Do When Cleaning a Restaurant Hood?

Most preventable problems come from using the wrong chemical, skipping hidden areas, or treating a routine wipe-down as a complete exhaust cleaning. Keep these restrictions in the staff procedure.

• Do not clean while burners, fryers, or metal surfaces are hot.
• Do not spray water or degreaser into motors, switches, lights, controls, or electrical connections.
• Do not use open flames, heat guns, or torches to soften grease.
• Do not mix cleaning chemicals or exceed the label concentration.
• Do not reinstall wet, damaged, backwards, or visibly clogged filters.
• Do not claim that cleaning the canopy and filters also cleaned the ducts or exhaust fan.
• Do not pour grease, concentrated degreaser, or greasy wastewater into a drain unless your local wastewater procedure specifically permits it.

When Should a Professional Clean the Hood System?

Arrange professional cleaning when grease is visible beyond the filters, when the system needs access panels or roof work, or whenever local rules require documented service. A trained technician should handle the full exhaust path rather than leaving ductwork untouched.

• Book service at the NFPA 96 or local-code interval for your cooking operation.
• Call sooner when smoke lingers, airflow declines, grease drips, or the fan becomes noisy or vibrates.
• Use a qualified contractor for solid-fuel grills, charbroilers, wok ranges, and high-volume fry operations.
• Ask whether the quote includes the hood, filters, ducts, fan, grease containment points, access panels, and exhaust outlet.
• Keep the service report and certificate with your fire-safety records and verify whether your insurer has contractor requirements.

What Should a Restaurant Hood Cleaning Checklist Include?

A useful checklist separates daily observation, routine filter cleaning, and scheduled professional service. Assign each task to a named role and require a supervisor’s sign-off where your food-safety system uses one.

• Each shift: check for visible grease, unusual smoke, blocked filters, dripping, noise, and damaged lights or panels.
• Weekly or as needed: remove, degrease, rinse, dry, inspect, and reinstall filters and grease cups.
• At each hood clean: wipe the canopy, clean accessible seams, inspect gaskets, protect food-contact surfaces, and verify airflow.
• At professional service: clean the full exhaust path, inspect the fan and access doors, photograph difficult areas, and obtain documentation.

Record the date, hood identification, filter condition, grease level, cleaning product, staff member, defects found, corrective action, and next due date. A log is useful evidence, but it does not replace a required certificate.

What Are the Signs a Hood Filter Needs Replacement?

Replace a filter when cleaning cannot restore its shape, drainage, surface, or airflow. A filter that looks clean but no longer fits tightly can still allow grease into the exhaust system.

• Warped baffles or frames that no longer sit securely in the channels.
• Crushed, torn, or permanently blocked mesh layers.
• Corrosion, pinholes, broken welds, sharp edges, or missing handles.
• Damaged gaskets, clips, or grease-drain openings.
• Persistent odor, smoke, or grease bypass after a correct cleaning.

Use the replacement part specified by the hood manufacturer, including the correct dimensions and airflow rating. Do not improvise with household range-hood filters in a commercial system.

How Should You Document Hood Cleaning for Safety and Inspections?

Keep a dated record for every routine filter clean and every professional exhaust-system service. The record should show what was cleaned, who did it, what problems were found, and when the next inspection is due.

• Write the hood or kitchen-area identification and the cleaning date.
• List filters, grease cups, canopy surfaces, ducts, fan, access panels, and outlet areas separately.
• Record the degreaser name, dilution, contact time, and any disposal method used.
• Note damaged parts, weak airflow, leaks, or safety defects, then document the repair or referral.
• Attach professional invoices, certificates, photographs, and the technician’s company details.
• Store paper or digital records for the period required by your local authority, insurer, or internal food-safety plan.

Food safety records work best when responsibilities and due dates are visible to the whole team. Keep this hood log alongside other cleaning procedures, such as the practical steps for cleaning grease from an air fryer, while keeping commercial exhaust work under its own fire-safety schedule.