Buying guide — home and kitchen

How to choose an air purifier

With dust and sandstorms, an air purifier becomes a serious question. What decides its value is the CADR against your room and the filter type and its availability, not the area printed on the box.

Published 2026-10-08

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What an air purifier does, and what it does not

In the dust and sandstorm season, fine dust gets in through gaps in windows and doors and through air-conditioning openings, hangs in the air and then settles on surfaces. A portable air purifier draws in room air and passes it through a filter that catches part of those particles. That is useful, but its limits are clear: it works on one room, not the whole home; it does not remove dust that has already settled on floors and furniture; and it does not replace sealing and closing windows during a storm.

So start with two questions: which room do you want to clean first, the bedroom, the majlis or the children's room? And how large is it, and how high is the ceiling? A unit that suits a small bedroom is not the one for a living room open to the kitchen.

Read the CADR, not the room size on the box

CADR, the clean air delivery rate, tells you how much clean air the unit delivers per unit of time for particles of a given size. The US Environmental Protection Agency explains it as the main basis for comparing air cleaners and advises comparing your room area with the unit's maximum recommended room size.

The trouble is that makers do not all calculate "recommended room size" the same way. The US Association of Home Appliance Manufacturers (AHAM) uses a two-thirds rule: the smoke CADR in cubic feet per minute should be at least two thirds of the room area in square feet. In the units you usually see here, that means roughly multiplying the room area in square metres by 12 to get the minimum CADR in cubic metres per hour, for a normal ceiling height. By that sum, you may find a unit that promises a large room on the box while its CADR suits a much smaller room under the rule, because the maker used different assumptions. Work it out yourself from the CADR, and treat the printed area as marketing until you have.

What really separates one unit from another

• A real filter. Look for a clearly named HEPA filter with a stated specification, and be wary of wording such as "HEPA-type" or "HEPA-like", which does not mean the same thing.
• A washable pre-filter. In a dusty environment, the pre-filter catches large grains and extends the HEPA filter's life. Ask whether it can be washed or vacuumed.
• Filter cost and availability. The filter is a consumable, and in dust season it fills faster than the manual suggests. Check that the original filter is available locally and roughly how often you will replace it.
• Noise at the speed you will use. CADR is measured at top speed. If you will run it on the quiet setting in a bedroom, the real cleaning is below the stated figure.
• The sensor. Many units show a PM2.5 reading, and desert dust also contains larger particles. The sensor helps you notice change, but it is not a precise measuring instrument.
• Ozone. The EPA warns against devices that deliberately produce ozone and are sold as air cleaners, and notes that some ionisers and plasma devices may emit ozone. Choose a unit that relies on mechanical filtration, or check that its ioniser can be switched off.

The practical classes

Power and placement

Power in Saudi Arabia is 230 V at 60 Hz and the common plug is type G. Choose the local-market version with an agent's warranty. Place the unit where air can flow in and out freely, away from curtains and walls by the distance the manual gives, and close windows and doors during dust so the unit is not trying to clean the whole outdoors.

Common mistakes

• Buying one small unit and expecting it to clean the whole home.
• Relying on the room size printed on the box without working it out from CADR.
• Running the unit with a window open on a storm day.
• Forgetting to clean the pre-filter after the dust season.
• Buying a unit whose original filters are not available in the Kingdom.

Before you pay

• Measure the room area and multiply by 12 for the minimum CADR in cubic metres per hour.
• Check the filter type, the availability of replacements and their life.
• Ask about noise on the quiet setting and whether the ioniser can be turned off.
• Compare listings on the Products page and look for a code on the Codes page.

For the dust that settles on the floor, the robot vacuum guide explains what to look for.

If someone at home has allergies or a breathing condition, ask their doctor what suits them; this guide is about choosing an appliance, not about treatment.

Options from well-known brands worth a look in

• Philips Series 800 AC0820/30 — A compact unit with a HEPA filter and a stated CADR of 190 m3/h per the listing; size your room from that figure.
• Philips Series 1000 AC1711/90 — A mid-size unit with HEPA and carbon filters and a PM2.5 sensor per the listing; check its CADR and filter availability.

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Limits of this guide

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• No price appears here. Price, availability, shipping and tax are set by the merchant at checkout.
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