In a kitchen, a dirty range hood filter is more than just a “cleaning issue.” It is a fire-risk warning sign, a hygiene problem, and an airflow problem. The Queensland Building and Construction Commission (QBCC) says that the range hood won’t work as well if the filters aren’t cleaned or changed often. The first line of defence against airborne grease is a filter. When they clog, the fan has to work harder, the room is filled with smoke and odours, and grease may begin to go into places you do not want it (rails, plenum entry, duct entry, fan housing).
This guide is specifically designed for kitchen areas, such as cafeterias in offices, staff kitchens equipped with cooking appliances, canteens, cafes, restaurants, food courts, clubs, schools, senior living facilities, and catering kitchens. It emphasises defined stop points for when professional duct and fan cleaning is necessary, as well as a safe, repeatable internal SOP for cleaning detachable filters.
What you’ll discover in this blog
- How to tell if a filter can be cleaned, needs replacement, or is overdue
- A safe, step-by-step method for cleaning baffle and mesh filters without damaging them
- How to clean the rails, ledges, drip areas, and canopy underside so grease does not come back fast
- Cleaning frequency guidance based on cooking load and inspection trigger
- Pass/fail checks to confirm the job is complete
- Where DIY must stop, and when to book professional duct and fan cleaning
- A copy-and-paste checklist and simple maintenance log for staff and compliance records
Download checklist (PDF):
Want a copy-ready SOP version? Download the Kitchen Range Hood Filter Cleaning Checklist (PDF) and copy it into your SOP for consistent cleaning and record keeping.
A crucial safety precaution
This guide only talks about the filter zone and the canopy surfaces that can be reached surrounding detachable filters. It doesn’t take the place of cleaning the exhaust system by an expert. Do not scrape, flush, or get to grease that is outside of the filter zone, such as in the plenum areas, duct entry, fan housing, or access panels. If you can see grease past the filters, stop and call a professional. This will keep you from pushing grease deeper into the system or making things unsafe. The Australian Institute of Refrigeration, Air Conditioning, and Heating (AIRAH) says that making it easy to check and clean can lower the danger of fires. If there is fuel (oil and grease) in the ducting, a kitchen fire that gets past the hood’s main grease filters can quickly spread. AS 1668.2 says that ducting must include access panels at every direction change that are “big enough to allow cleaning of ducts.”
First, determine the type of filter in your kitchen range hood (clean or replace).
Verify the filter you have before you begin. The type of filter used in kitchen range hoods is often one of the following, and the appropriate method depends on whether the filter is meant to be replaced or cleaned. Poor airflow and residual grease odours can result from cleaning the incorrect kind, which can cause harm.
A) Baffle filters made of stainless steel
Stainless baffle filters are designed to handle larger amounts of grease. Grease droplets escape before the air travels farther into the system because they employ metal channels that push the air to change direction. These filters are frequently found on fryers, grills, woks, and high-output cooking lines since they are robust and typically the simplest to clean and reuse. Reinstalling them incorrectly is the primary error. For grease to effectively drain into the collection area rather than blow through, baffle filters must be reoriented.
B) Mesh filters made of aluminium
Although aluminium mesh filters may be cleaned, they clog more quickly and are more easily bent or distorted when being handled. Compared to baffle filters, they can be more difficult to completely degrease since grease gets trapped in the mesh layers. Additionally, they are vulnerable to severe chemicals. Over time, strong caustic degreasers can limit the filter’s life and make it more difficult to maintain cleanliness by discolouring aluminium and pitting its surface. If you use aluminium filters, make sure the products are safe for aluminium and steer clear of vigourous washing that could cause the frame to deform.
C) Carbon or charcoal filters (recirculating or ductless systems)
Typically, carbon filters are not made to be washed. They are employed in recirculating or ductless systems that filter odours before reintroducing air. Even though the filter appears good after washing, the carbon media can be damaged and performance can be decreased. Generally speaking, you should replace these filters according to the manufacturer’s recommendations, or sooner if you observe that the airflow is decreasing or that odours are returning quickly.
D) Replacement Programmes for Disposable Grease Filters
Disposable grease filters are used at some locations as part of a replacement programme. You are not supposed to clean these. After they are loaded, they can become difficult to manage and obstruct ventilation. If they appear heavy, clogged, or saturated, replace them sooner rather than later. It’s usually an indication that the disposable filter is past due if employees notice increased heat, haze, or odour during service.
As a general rule, aluminium mesh and stainless baffle filters are typically reusable and washable. Typically, carbon or charcoal filters should only be changed because washing can destroy them. If you’re not sure, consult your maintenance provider, the hood handbook, or the label on the filter frame.
Safe, hygienic kitchen hood filter supplies and equipment
- Gloves resistant to chemicals
- Eye protection
- Non-slip shoes
- Apron (useful but optional)
- A non-scratch scrub pad or nylon brush
- Big soak tub, wash trough, or sink
- Warm water
- kitchen degreaser (see the SDS and label instructions)
- Disposable wipes or clean cloths
- Drain board or drying rack
- For moving filters, use a shallow container, absorbent pads, or a drip tray.
- If necessary, a waste container or a grease collection container
Don’t do this
- Metal scourers or wire brushes (damage filters and coatings)
- Chemical mixing (never combine bleach with other cleaning agents)
- Unrestrained use of caustics, particularly on aluminium mesh
- Grease is sprayed into drains by pressure without containment.
- Commercial safety setup (do this every time)
How to take off and soak kitchen range hood filters without getting grease everywhere?
This is where advice for businesses is different from guidance for homes. You need a configuration that protects the site, the crew, and the surfaces all the time.
Step 1: Turn Off Safely
First, turn off the cooking equipment so you don’t have to work around hot or splattered food. If your site has one, use the right wall switch or isolator to turn off the hood fan. Let the kitchen hood and filters cool off completely. When you mix hot metal with degreasers, it can generate burns, intense fumes, and rapid chemical reactions, which make the work more dangerous than it needs to be.
Step 2: Keep the Area Safe
Make sure the area is set correctly so that grease and water don’t spread around the kitchen. Put absorbent pads or a tray under the filter area to catch any drips that fall when you take and transport the filters. Have a wet floor sign ready because the floor can get slippery very quickly. Keep food, clean utensils, and any open containers out of the splash zone so that nothing gets dirty while you’re spraying, washing, or rinsing.
Step 3: Chemical Control and PPE
Before you touch greasy filters or chemicals, put on gloves and eye protection, use a degreaser that is safe for use in the kitchen and follow the instructions on the package for how much to dilute it and how long to let it sit. Stronger is not always better and can hurt some metals. When using chemicals, keep the label visible and don’t pour them into bottles that don’t have labels. This makes it more likely that someone would misuse them and makes it harder for others on shift to handle them safely.
Step 4: Control grease and wastewater
Keep an eye on where the grease goes. You shouldn’t wash heavy grease straight down the drain. If you can, use a sink strainer or catch device to catch solids and keep them from getting stuck. Before soaking or rinsing, put heavy grease in a trash can and wipe or scrape it off. This keeps your wash water cleaner, makes the outcomes better, and lowers the risk of plumbing problems.
The Complete Method for Cleaning Kitchen Hood Filters
This method works for most stainless steel baffle filters and a lot of mesh filters, as long as you are careful with the mesh filters and don’t use strong chemicals on aluminium. Here is the whole technique for cleaning a kitchen hood filter.
Take out the filters without getting grease everywhere.
Take the filters out slowly and maintain them level so that grease doesn’t drip. Put each filter right into a tray or tub as soon as it comes out. This will catch any drips and keep grease from getting on the floor. If you’re using baffle filters, make sure you know how they sit in the rack. Many of them are directional and need to go back in the same way to drain effectively.
First, dry scrape or wipe off the heavy grease (optional but helpful)
If the filters contain heavy clumps or sticky build-up, use disposable cloths to clean or scrape that off first and then throw it away right away. This minor step makes a tremendous impact because it keeps your soak water from getting greasy too quickly, which keeps the degreaser functioning correctly instead of just moving oil about.
Rinse with hot water first
Before you soak the filter, rinse it with hot water to loosen the grease on the surface. Direct the water flow so that oil goes into the sink and doesn’t spray back onto nearby benches, walls, or clean tools. This pre-rinse also helps the degreaser get to the hard-to-reach spots faster.
Get the soak ready
Put hot water in a tub or sink, then add degreaser according to the label’s instructions. Don’t use too much; more chemicals don’t mean better cleaning and can hurt some metals. If you can, fully submerge the filter so that the solution may break down grease on both sides.
For little grease, soak for about 10 minutes; for moderate grease, soak for 15 to 20 minutes; and for substantial build-up, soak for 20 to 30 minutes or two shorter cycles with new solution. If the water gets hazy and oily soon, you should drain it and replenish it again. When cleaning unclean water, a new remedy works better than scrubbing hard.
Clean the filter without hurting it.
When cleaning stainless baffle filters, use a nylon brush and scrub along the baffle channels instead than across them. Brush along the direction of the channels to make sure that airflow passages are clear. Pay special attention to corners, edges, and the lower lip, where grease tends to collect.
Use a gentler nylon brush or a non-scratch pad on aluminium mesh filters and don’t press too hard. Don’t bend the frame, and don’t use harsh chemicals or scrub too hard, because mesh filters might change shape and be tougher to clean effectively in the future.
Rinse well until the water is clear.
Rinse the filter on both sides, paying special attention to seams, corners, and passages where grease likes to hide. Keep rinsing until the water is clear and the surface doesn’t feel slippery. If you still feel a greasy film after rinsing, soak it again and scrub it lightly. This works better than scrubbing it hard.
Let it dry completely before putting it back on.
Put the filters on a rack so they can drain and dry out completely. Don’t put the filters back in while they are still moist. Wet filters can hold dirt, drop into cooking areas, and make smells come back quickly.
Put things back together with the right fit and direction.
Put the filters back in so they fit snugly in the rack with no gaps. Gaps let air and grease get past the filter and go deeper into the system. Check the direction of the baffle filters again; many feature arrows or a drain orientation that must be facing the right way for the grease to drain properly. The rules set by Energy Safe Victoria say that there should be enough space between machines and overhead filters to keep everyone safe. Clean your grill, oven, and range fan. It is possible for grease and fat to build up and catch fire. Metal things should not be put in the microwave. It’s going to spark.
What else should you clean so that grease doesn’t come back quickly?
Grease frequently comes back quickly if you merely wash the filters because there is still a grease line in the rails, ledges, and underside of the hood. The next time you use the hood, the airflow will draw the residue back onto the freshly cleaned filters, and you’ll have sticky buildup and a bad smell sooner than you thought. Cleaning these places every time you clean the filters will help keep them from getting dirty again.
A) Ledges and Filter Rails
Wipe off the ledges and rails where the filters rest. Grease builds up there first and makes a dark “grease line” at the places where air comes in. Pay attention to the borders where air comes into the hood. This is where dirt gets back on the filter frame. If you do it often, a quick wipe with a degreaser and rinse is typically all you need.
B) Grease the gutter and the drip tray (if you have one)
Each time you use your hood, make sure you empty and clean the gutter or drip tray. Clean and degrease the tray and the channel it sits in, then make sure it is properly installed when you put it back in. Grease can drip back down, spread to the bottom, and cause smells and hygiene problems quickly if it isn’t sitting straight or is overflowing.
C) The bottom of the canopy around the filter opening
The region around the filter hole on the bottom catches greasy haze and spatter that filters don’t catch, so spot clean it. Grease tends to collect in seams, corners, and the bottom lip, so be careful. When you need to clean lamp covers, be careful and turn off the power. Then, wipe them dry so that no residue is left that would collect dust.
D) Walls and splash zones close by
If you can see sticky stuff on walls, tiles, or other surfaces along the cooking line, clean it up while you have pads, chemicals, and rags handy. This keeps grease from getting back on the equipment and makes the kitchen feel less greasy, which is something staff notice even when the hood looks clean.
Important: When to Stop and Call a Professional
If you see a lot of grease outside of the filter zone, like inside the duct entry, behind panels, or near the exhaust fan, stop right away. To keep grease from going deeper, leaking, or making things unsafe, certain locations need particular access, containment, and safe cleaning methods.
How often need to clean the range hood filters in your kitchen?
There isn’t a set amount of time that works for everyone. How much oil your kitchen makes and what you notice during regular checks can help you decide on the proper schedule. Set up a programme for inspections that works with your cooking load and keeps ventilation and fire risk problems from getting worse by using the table below.
| Usage level | Examples | Inspection frequency | Filter cleaning frequency |
| High grease operations | Fryers, chargrills, woks, heavy sauté lines | Daily quick check + weekly formal check | Weekly, sometimes more often |
| Moderate grease operations | Steady service, mixed cooking, limited frying | Weekly | Weekly to fortnightly |
| Light commercial use | Office cafeteria with limited hot cooking | Weekly to fortnightly | Fortnightly to monthly (based on build-up) |
Events and spikes: increase inspection and cleaning after office events, seasonal peaks, menu changes, or staff changes.
Simple inspection trigger: if the filter feels sticky, looks shiny with a grease sheen, or airflow seems weaker than normal, clean it now.
How to tell if the Kitchen Range Hood Filter has passed or failed quality tests?
These checks should be passed by filters once they have been cleaned:
Test by touch
- Put on a glove and run your finger along a baffle channel or mesh surface.
- Pass: no film that sticks.
- The Complete Method for Cleaning Kitchen Hood FiltersFail: there is still sticky residue.
- Check the flow path
- There should be no obstructions in the baffle channels or mesh apertures.
- Pass: pathways that are clearly open.
- Fail: channels that are blocked or mesh that is too tight.
Check the fit and seal
- There are no gaps between the filters.
- Pass: stable and sitting correctly.
- Fail: gaps, a loose fit, or a frame that is bent.
Check for drips when you resume.
- After reinstalling and restarting the fan, keep an eye out for drips for a few minutes.
- Pass: no leaking.
- Fail: leaking means there is grease left over, the seat is not level, or the gutters are overflowing.
Signs of operation
- Less noise, better smoke capture, and less smell.
- The problem may be deeper in the system if performance doesn’t get better.
Troubleshooting: Common problems and how to fix them when cleaning the kitchen hood filter
Issue: The filters look clean, but the smoke still stays in the kitchen
If you clean the filters and there is still smoke and steam, the problem is probably not with the filter bank. Grease can build up at the plenum entry, duct entry, or exhaust fan, blocking airflow in places that are hard to perceive. It can also happen if the filters are put in the wrong manner (the baffle orientation) or if there are minor gaps that let air through the filter.
First, make sure that each filter is firmly installed with no gaps and that the baffles are pointing in the right direction. Then, with a flashlight, examine just past the filter zone for grease that you can see. If you can see sticky buildup past the filters, call a professional to clean and check the duct and fan in your exhaust system.
Problem: Grease Keeps Dripping After Cleaning
If grease resumes dripping after cleaning, it usually signifies that the drip tray or grease gutters are still full or overflowing, which is why the hood keeps leaking grease back down. Another common culprit is putting filters back in while they are still wet. This can dislodge any leftover dirt and cause drips when the system warms up. Sometimes, thick grease becomes stuck in channels or mesh and needs to be cleaned again.
To fix the problem, clean the gutters and drip tray again, wipe the sides of the hood where grease builds up, and make sure the filters are totally dry before putting them back in. If the drips don’t stop, saturate the area again with a new solution and clean the seams, corners, and lower edges where grease builds up.
Issue: The aluminium mesh filter gets dull or dark.
When the chemical is too powerful or doesn’t work well with aluminium, or when the filter is left soaking for too long in a strong solution, the aluminium mesh filters might become dull, black, or discoloured. This is something that a lot of people do wrong when they use heavy-duty degreasers on tougher surfaces.
Use a milder degreaser that is safe for aluminium, soak it for less time, and scrub it gently instead of using harder chemicals to get it clean. If the filter stops working well, the mesh changes shape, or the airflow is noticeably less, it’s usually safer to replace it.
Problem: Employees are complaining about fumes or skin irritation
Usually, fumes and skin irritation mean that there are problems with chemical control. This can happen if the area isn’t well-ventilated when cleaning, if the degreaser is mixed too vigorously or handled carelessly, or if the PPE is absent or not right for the job.
Solution: The first step to fixing the problem is to follow the directions for diluting the chemicals and keep them in marked containers. Try to improve ventilation as much as you can while cleaning, and don’t spray in small spaces where vapours build up quickly. Make sure that all employees use the right personal protective equipment (PPE), such as gloves and eye protection. Also, make sure that everyone gets more training on how to safely handle chemicals and what to do if they start to irritate.
If you see any of the following signs, call a specialist:
- Grease that you can see within the duct entry or surrounding access panels: Grease has gotten past the filters and is now building up inside the duct. This makes it more likely for a fire to start and can also slow down airflow.
- Grease leaking from the fan housing, duct joints, or seams: There is too much grease in the system, and it is leaking from the joints. This usually signifies that more than just the hood region has to be cleaned.
- Even with clean filters, smoke or heat keeps coming back: Airflow isn’t working right. A common reason is that grease has built up in the plenum, ducting, or fan, or there is an issue with the airflow in the machine.
- Strong burnt-grease smell that won’t go away: Old grease is stuck in the system and reheats during service, generating smells that come back soon after basic cleaning.
- Staff can’t get to the roof fan or it’s too dangerous for them to do so: Working at heights and getting to the roof can be dangerous. Trained experts with the necessary safety controls should take care of this.
- For a landlord, an insurance company, or an audit, you need compliance documents. A professional like Westlink Commercial Cleaning can safely check and clean the duct and roof fan for full-system cleaning and compliance documentation.
- Heavy buildup that can’t be safely reached: If grease is thick, sticky, or in tight spaces inside the system, cleaning it yourself can be dangerous and may drive the grease deeper into the system.
Why This Is Important
When professionals clean ducts and fans, they use the right tools, contain the waste properly, and handle it safely so that oil is removed instead of being pushed deeper into the system. It also keeps your kitchen staff safe from dangerous access work and helps restore extraction performance along the entire grease path, not just the filters.
Conclusion
Clean range hood filters are your first control for grease, smoke, and odours, but they only work when they are cleaned safely, dried fully, and reinstalled with the correct fit and direction. Use an inspection-based schedule, clean the rails and drip areas every time, and record each clean in your log. If grease is visible beyond the filter zone or performance does not improve after filter cleaning, stop and book professional duct and fan cleaning to restore airflow and reduce fire risk.
Frequently Asked Questions
Is it possible to clean baffle filters in an industrial dishwasher?
Yes, most of the time, but only if the filter maker says it’s okay to clean it in the dishwasher and the dishwasher can handle the size and amount of grease. A soak-tank clean usually works better for getting rid of a lot of grease. Always rinse filters well and let them dry completely before putting them back in.
Do we need to take down the hood covers or access panels to clean inside?
No. You should only clean the inside of the filter zone and the canopy surfaces that are easy to get to. If you can see grease inside the duct entry, behind panels, or near the fan housing, you need to hire a professional to do the work.
How can I clean filters quickly without hurting them?
Use hot water, a properly diluted degreaser, and enough time to soak. Then, finish with a nylon brush. First, let the soak break down the grease. Scrubbing too hard bends mesh and breaks frames.
How do we keep filters from getting greasy again so quickly?
Not just the filters, but also the rails, ledges, and drip tray should be cleaned every time. Put the filters back in with the baffle facing the right way and no gaps. If you have more to clean up after cooking, clean it more often.
What are some signals that it’s time to hire a professional to clean our ducts and fans?
It’s time to schedule a full-system clean if smoke or smells stay after cleaning the filter, grease is visible past the filter bank, the fan gets louder, grease drips from seams or joins, or build-up is visible near the duct entry or fan housing.
How long do filters need to dry before you put them back in?
Only reinstall when the item is completely dry, not just drip-dry. Damp filters can make drips happen, trap dirt, and bring smells back faster. Use a drying rack and give yourself extra time in kitchens that are damp.
How do we know if we should clean a reusable filter instead of replacing it?
If the frame is bent, the welds are broken, the channels are damaged, the mesh is crushed, it doesn’t fit tightly anymore, there is corrosion, or smells stay even after cleaning, you need to replace the filter.
Are caustic degreasers safe to use on aluminum mesh filters?
Not all the time. Strong caustics can make aluminum darker, pitted, or weaker. Use a degreaser that says it is safe for aluminum, cut down on the time you let it soak, and scrub it gently.
Can we pressure wash filters?
Avoid uncontrolled pressure washing. It can force grease deeper into the filter, spread contamination, and push grease into drains without proper capture. If you rinse, do it in a controlled sink or wash bay with strainers and grease capture.
What should we record in the maintenance log for compliance and consistency?
Record the filter type, cleaning date and time, who cleaned it, method and chemical used, soak time, issues found (damage, drips, grease beyond filter zone, smoke or odour complaints), actions taken, and whether a professional follow-up is needed.
