Does an Air Purifier Really Help With Haze? What It Can and Can’t Do

Yes, an air purifier helps with haze, but only with a True HEPA filter, enough CADR for the room and the windows shut. Here’s how to tell if yours is working.

On this page

1. Does an Air Purifier Help With Haze? The Short Answer
2. When an Air Purifier Won’t Help
3. How to Make Sure Your Purifier Is Actually Working
4. Two Purifiers That Pass the Test
5. Buying on Shopee: What to Check
6. What If Your Model Is Discontinued and You Can’t Find the Filter?
7. So, Is an Air Purifier Worth It for Haze?

Every haze season the same question comes up in family WhatsApp groups: does an air purifier help with haze, or is it an expensive box that hums in the corner? The honest answer is yes, it can make a real difference to the air you breathe at home, but only if three things are right. Many purifiers sold in Malaysia get at least one of them wrong.

This guide explains what an air purifier actually does to haze, when it won’t help at all, and how to check that yours is doing its job. At the end are two models that pass every test, one for the bedroom and one for the open-plan living room.

Some links in this article are Shopee affiliate links. If you buy through them, rumaruma may earn a small commission at no extra cost to you. We chose these purifiers on filter type and CADR first, and only then looked for where to buy them.

Does an Air Purifier Help With Haze? The Short Answer

Haze is mostly fine smoke particles called PM2.5, small enough to get deep into your lungs. Those particles slip in through window gaps, door frames and the loosely packed hole around the aircon piping, so indoor air during a bad haze week can be nearly as dirty as the air outside.

A purifier with a True HEPA filter (H13) traps at least 99.97% of particles at 0.3 microns, which covers PM2.5. Run in a closed room, it pulls the same air through that filter again and again, and the PM2.5 level indoors drops well below the reading outside, often within half an hour. You can see it happen on a purifier with a PM2.5 display, or with a cheap standalone air quality monitor.

What that buys you is a room where you breathe cleaner air for the hours you’re in it, usually the bedroom at night. That matters most for young children, older parents, and anyone with asthma or a heart or lung condition.

What it doesn’t do is make haze harmless. It only cleans the room it’s in, and it won’t treat symptoms you already have. If someone at home is struggling to breathe, see a doctor rather than relying on a machine.

When an Air Purifier Won’t Help

Most “it didn’t work” stories come down to one of these:

• It isn’t True HEPA. “HEPA-type”, “HEPA-like” or a filter with no H-grade lets much of the PM2.5 through.
• It’s too small for the room. A purifier sized for a bedroom won’t keep up in a 30 m² living room. Look at the CADR (clean air delivery rate), not the “up to 100 m²” claim on the box.
• The windows or doors are open. Fresh haze flows in faster than the purifier can clean it. Shut the room and seal the obvious gaps.
• The filter is clogged or loose. An old filter moves far less air, and a badly made replacement that fits loosely lets air leak around the edges without passing through the HEPA layer.
• It relies on an ioniser or ozone. These don’t replace a HEPA filter, and ozone irritates the lungs. Choose one with no ozone generator, and treat any ion feature as an extra, not the thing that cleans the haze.
• It humidifies too. Malaysian homes already sit at 60–80% humidity. Extra moisture brings the risk of mould behind wardrobes and on ceilings, so if your purifier has a humidifying function, you rarely need to use it here.

A purifier also does little for the smoky smell and gases in haze unless it has a decent activated carbon layer, and even then the effect is modest. The health benefit comes from removing the particles.

Can’t the Aircon Do the Same Job?

No. A wall-mounted split aircon, the kind in most Malaysian homes, only recirculates the air already in the room, and its filter is a coarse mesh that catches dust and hair but lets most PM2.5 through. It cools the room without cleaning the haze out of it. It’s still worth running, because a cool room means nobody opens a window in the afternoon, but the purifier does the cleaning. Our haze guide explains what your aircon can and can’t do during haze.

How to Make Sure Your Purifier Is Actually Working

Measure the room, multiply length × width × ceiling height (most Malaysian homes are about 2.7 m), then multiply by 5. That’s the minimum CADR in m³/h for about five air changes an hour, which is what you want during haze.

Pick a purifier above your number so it can run on a quiet low setting and still keep up. Then:

• Close the door and windows, and run it before the room gets bad, not after.
• Give it about 30 cm of clear space around it, near where people sleep or sit.
• Watch the PM2.5 reading. If it doesn’t come down within an hour, the room is too big, too leaky, or the filter needs changing.
• Buy a spare filter at the start of haze season, when stock runs out fastest.

Our guide on how to protect your home from haze covers setting up a clean room step by step, including how to seal sliding doors and louvre windows.

Two Purifiers That Pass the Test

Prices are for reference only, based on Malaysian listings checked in October 2026. They change with Shopee vouchers, mega-sale days (such as 11.11 and 12.12), seller and stock. CADR figures are the manufacturers’ own.

Cuckoo i Model: For the Bedroom

The Cuckoo i Model is a compact, quiet purifier for the room you sleep in. Its CADR of 219 m³/h covers a standard Malaysian bedroom by the volume × 5 rule, with a little margin for the low setting at night. It uses a True HEPA H13 filter with a deodorising layer, and its Auto mode raises the fan speed when the dust sensor picks up worse air.

Good to know: Cuckoo recommends replacing the filters every four months, more often than most brands, so check whether your listing bundles spares. Leave the separate Ioniser mode off. Cuckoo rates it for 32.9 m², but that assumes fewer air changes than you want during haze, so keep it to one bedroom.

See the Cuckoo i Model on Shopee

Mijia Smart Air Purifier Max: For Open-Plan Living Areas

The open-plan living and dining area of a terrace house or large condo is where most purifiers fail, because the air keeps mixing with the kitchen and the stairwell. At just over 1,000 m³/h, the Mijia Max delivers about four and a half times the clean air of the Cuckoo, so it can sit on low in a 30 m² living room, quiet enough to watch TV beside, and still keep up.

Good to know: Its UVC modules are a bonus for germs but don’t change how it handles haze; the HEPA filter does that work. At about RM2.30 per m³/h of clean air against the Cuckoo’s RM7, it’s far better value for big spaces, but overkill for one bedroom. It stands about 76 cm tall, so it needs a floor spot.

See the Mijia Smart Air Purifier Max on Shopee

Buying on Shopee: What to Check

Our links go to Shopee sellers carrying these models, not the brands’ own stores. Wherever you buy, check that the listing states a Malaysian warranty (grey imports may not be covered or carry the SIRIM label), the model number matches, the seller has a solid rating and recent reviews, and replacement filters are easy to find for your model.

What If Your Model Is Discontinued and You Can’t Find the Filter?

It’s a fair worry. A purifier lasts many years, but brands replace their models every year or two, and once a model is discontinued its official filters get harder to find.

We’ve been through this ourselves. Our office runs a Sharp air purifier, model KCG40LW, and when Sharp moved on to newer models, the official replacement filters became hard to track down. The purifier itself still works perfectly well. It takes three filters:

What saved us is that popular models have plenty of third-party filters made to fit them, and Shopee carries many of them. Even after a manufacturer stops making a purifier, you can usually still buy a filter for it. This is the replacement filter we use for our Sharp purifier.

To pick a third-party filter that does the job:

• Match the model number exactly, not just the brand or the size.
• Look for a stated HEPA grade, ideally H13, rather than vague “HEPA-type” wording.
• Check the reviews for fit. Buyers will mention if it sits snugly in the frame or leaves gaps around the edges.
• Watch the PM2.5 reading after you change it. If the room clears as fast as it did with the old filter, the new one is working.

A note on our Sharp: it releases ions into the air alongside the HEPA filter, so if you like having that ion feature, it’s a good choice. It’s also a humidifying model. If you use the humidifier, clean the water tank every month. We found an orange stain building up in ours surprisingly fast.

So when you choose a purifier, pick an established brand with a popular model. More units sold means more filter makers will keep supporting it long after it leaves the shops.

So, Is an Air Purifier Worth It for Haze?

If you or someone at home is sensitive to haze, yes, as long as you buy the right one and use it properly:

• True HEPA (H13) filter, not “HEPA-type”
• CADR above your room’s volume × 5
• No ozone generator, and the humidifier off unless you really need it
• Door and windows shut while it runs
• A spare filter ready for haze season, original or a well-reviewed third-party one

Get those right and the next hazy week looks different: the door shut, the purifier humming on low beside the bed, its display showing a single-digit PM2.5 reading while the city outside is grey.