What Size Air Purifier Do I Need | Air Health

The air purifier's size depends on the room you will use. If you are going to buy a portable air purifier for a certain area, it is necessary to consider the size of the space. This means that you need to know not only calculate the size of the space but also the performance of the air scrubber. 

This guide will look at space, key specifications, air change frequency and contaminants, air scrubber filter explore air cleaner categories, features to teach you to choose the best air scrubber for the best home or commercial use.

 

Part 1. Choosing an Air Scrubber for Small and Large Rooms

 

People often ask if large air purifiers can be used in small rooms. Or can you use a small air purifier in a large room? This kind of question, in fact, the best choice is how big is the size is the most appropriate however, but there are other answers, and you will be presented with other answers below.

 

Will a Large Air Purifier Work in a Small Room?

 

Generally speaking, if your area is 300 square feet you can go for an air scrubber that can cover 300-500 square feet because air scrubber that deal with less than your area will not deal with it as well as it should and not be very effective.

If it's larger than your space, it's worth its weight in gold as far as air purification efficiency is concerned. It also doesn't incur unnecessary filter replacement costs. But don't go for a machine that is too big, like one that can cover 1000 square feet, although it can do a good job but you'll spend more on electricity and get the same results as if it covered 500 square feet.

 

Can You Use a Small Air Purifier in a Large Room?

 

Can be used, but not recommended.A  smaller capacity purifier may operate more quietly, but it might not clean the air as efficiently, particularly in larger rooms. It is recommended that you use one that is as big as or covers an area larger than the size area. 

Another option is a smaller air purifier, but one that can be daisy-chained to extend the coverage area, such as the Alorairscrubber Cleanshield HEPA 550 machine, which on its own has a CFM of 270-550, but when you connect three of them together, it has a CFM of 1,650.

which means that it will cover an area of That means that what was originally a coverage area of That means that the original coverage area was 800 sq. ft. and now the coverage area can be about 3,220 sq. ft.

If you like the idea of a machine that you can DIY the size of your space, come to Aloraircrubber and choose.

 

 

Part 2. Understanding Air Purifiers: Key Specifications

 

When choosing an air purifier, one should know some critical parameters that indicate its efficiency. Crucial factors include ACH and CADR, noise level, and many more. All of them influence the efficiency of an air purifier in your environment in one way or another. 

Clean Air Delivery Rate or CADR  

CADR measures the effective volume of clean air (filtered air) delivered by an air purifier per minute.CADR is specifically designed to remove specific pollutants such as dust, pollen, and smoke. It typically targets three common indoor air pollutants: soot, pollen particles and dust particles.

AHAM sets the CADR through standardised testing.The higher the CADR value, the better the air purifier will perform. When choosing an air purifier, consider the CADR of the room area, which should be at least two-thirds of the room area. How do I know what the CADR is? One way is to check it by reading the product's specification and user manual, or if it is not shown, you can calculate the result using the Airflow Range* filtration efficiency. 

For example, the PureAiro HEPA Max 970 from Alorairscrubber has an Airflow Range of 270-750CFM, a capture rate of 99.95%, and a maximum flow rate of 750, which gives a CADR of 749.625, which approximates the maximum area covered by the product at 1124.

Air Changes per Hour (ACH)

ACH is the amount of fresh air supplied or stale air circulated in an hour. Different ACHs apply to different situations. For example, ACH 4 means that the air in a room is completely changed four times per hour, approximately every 15 minutes, and is intended for use by people with low levels of air pollution. 

ACH 5 means that the air in a room is completely changed five times per hour, with the air being circulated every 12 minutes, and is intended for use in environments with moderate pollutants, such as homes with pets or a small amount of smoking habits. 

ACH 6 represents a complete change of indoor air six times per hour, with air changed every 10 minutes, for spaces with high levels of contaminants or for sensitive populations.

Applicable Area

When choosing an air purifier, you should pay attention to the maximum square footage or square metre area that the purifier can handle. The area of such devices equals or even exceeds the area of the room to provide maximum air purification. Manufacturers usually give square feet or square metres of coverage. You can find out by reading their product specification sheets can tell.

Filter Types 

Air purifiers take air and use different types of filters to capture and eliminate airborne pollutants. There are three main types of filters: HEPA filters, activated carbon filters and prefilters.

• HEPA Filter (High Efficiency Particulate Air Filter): Captures 99.97% of particles as small as 0.3 microns, including dust, pollen, mould and bacteria.
• Activated carbon filters: adsorb odours, smoke, VOCs (volatile organic compounds) and chemical fumes. Often used in combination with a HEPA filter for complete purification.
• Pre-filters: Capture larger particles such as dust, hair and pet dander, extending the life of HEPA and carbon filters. Often washable and reusable.
• UV-C Light Filters: Use ultraviolet light to kill or inactivate bacteria, viruses and other microorganisms. Usually used in combination with other filters.
• Ion Filter/Ioniser: Releases charged ions that attract airborne particles, causing them to be dislodged from the air or collected on an electrostatic plate.
• Antimicrobial filters: agents that inhibit the growth of bacteria and moulds are embedded in the surface of the filter to extend the life of the filter and improve cleanliness.
• Photocatalytic oxidation (PCO) filters: use UV light and a catalyst (usually titanium dioxide) to break down pollutants at the molecular level, effectively inhibiting volatile organic compounds and microorganisms.

 

 

Noise Level

Noise is usually expressed in decibels (dB), with low dB indicating low noise and high dB indicating high noise. The noise level of air scrubbers varies from one performance to another, for example, the ones for home use or bedroom use are usually silent or below 30 decibels, but in commercial use it is usually between 60-80 as it needs to handle a larger area. The noise level of air scrubbers ranges between 20 and 70 decibels. So you have to depend on your environment

Energy Consumption 

Another feature is the power consumption of the air purifier as it determines your electricity bill and the efficiency of the air purifier. 

This is where you should find out the wattage of the product, the current amperage to calculate the power of the product and then multiply it by how much electricity costs per hour for one kilowatt and then multiply it by the time of the year, say a month, a year, and you will be able to find out how much you will be spending on your electricity bill.

Smart Functions 

With the same basic features, you can find out if it has any other additional features such as touch control, smart wifi control, auto drain, and so on.

Related reading: Where is the Best Place for an Air Purifier?

 

Part 3. What Size Air Purifier Do I Need?

 

When choosing an air purifier, one that is too small will not purify the air effectively, while one that is too large may waste energy. Here is a comprehensive guide to help you determine the right size air purifier for your needs.

 

Step 1: Know the Size of Your Room

 

Firstly, measure the size of the room in which you intend to use the air purifier. Start by measuring the length and width of the room. Multiply these dimensions together to get the total area. For example, a 15 ft. x 20 ft. room has a total area of 300 square feet. You can calculate the volume of the space you are in by measuring the height, for example, if the height is 8 ft, the total volume of the room is 300 sq ft * 8 ft = 2400 cubic feet.

 

Step 2: Consider Air Changes Per Hour (ACH)

 

Air cleaners are rated according to the number of times per hour they can filter the air in a room. The recommended air changes for different situations are

• Standard room: 4 to 6 ACH
• Allergy or asthma sufferers: 6 to 8 ACH
• Highly polluted areas: 8 to 10 ACH

To calculate the amount of airflow required, multiply the volume of the room by the required ACH and divide by 60 to get the cubic feet per minute (CFM) required. For example, if the room is 2400 square feet and the required ACH is 6, the formula would be (2400 cubic feet x 6 ACH)/60 = 240 CFM.

 

Step 3: Check the CADR rating of your air purifier

 

Clean Air Delivery Rate (CADR) measures the amount of clean air produced by an air cleaner. Select a unit with a CADR rating that meets or exceeds the CFM required for the calculation. For example, if a 300 cubic foot room requires 200 CFM, choose an air cleaner with a CADR rating of at least 200 because the machine's filtration efficiency also needs to be considered.

 

Step 4: Consider Room Conditions

 

Consider other factors that may affect the performance of your air cleaner:

• Ceiling height: If your room has high ceilings, adjust the required CADR or CFM accordingly; higher ceilings mean more airflow.
• Room usage: Rooms with a lot of activity or frequent cooking may require a higher CADR because of increased airborne pollutants.

 

Step 5: Choose the right air purifier

 

Based on your calculations and room conditions, choose an air cleaner that meets these criteria. Make sure it provides the necessary CFM and CADR values. Some recommended choices include.

 

Air Purifier Sizing Guide: Room Sizes and CADR Requirements

 

Room Size (Square Feet)	Recommended CADR (CFM)	Suitable Areas
200-300 sq. ft.	130+ CFM	Home offices, nurseries, small bedrooms
300-500 sq. ft.	200-250 CFM	Small living rooms, master bedrooms, studio apartments
500-800 sq. ft.	300-400 CFM	Large family rooms, open kitchen areas, large offices
800-1,200 sq. ft.	400-500 CFM	Combined living/dining areas, small apartments, open offices
1,200-2,000 sq. ft.	500-650 CFM	Open-plan homes, large offices, small commercial spaces
2,000-3,000 sq. ft.	650-800 CFM	Entire floors, large open-plan homes, commercial areas

 

 

What is the Best Large Room Air Purifier?

 

When it comes to choosing the right air purifier for a large room, Alorairscrubber can make it easy for you. It has developed a number of air purifiers including the best air purifier for mould, UV air purifier and many more.

Here are three air purifiers from Alorairscrubber for you:

The first, Cleanshield HEPA 550, has an airflow rate of 270 CFM-550 CFM and a capture efficiency of 99.95%. It fits an area of 800 square feet.For fire and water damage restoration, carpet drying, warehouses, wood floor drying, concrete pouring, kitchens, factories.

The second, the PureAiro HEPA Max 870, has an airflow rate of 270 CFM-550 CFM, and consists of a four-stage filtration system made up of Pre-filter, HEPA Filter, Carbon Filter and UV-C Light. With a noise level of less than 65 dB.Captures a wide range of volatile organic compounds (VOCs) including soot, smoke, food odours, fumes from paints and paint thinners, sewer odours and many other compounds. It is an option for areas with odours and high levels of pollution.

The third, the DecDust V2 Pro, has a coverage area of 20,000 cubic feet and an airflow of 800-2,000 CFM and is designed for large spaces such as industrial and commercial renovations, shop printing, construction sites, water and fire damage restoration, factory wastewater remediation, lobbies, hotels, schools, and large office spaces.

Conclusion 

Choosing the right air scrubber for the size of your space will not only keep the air fresh but also maximise energy efficiency.Alorairscrubber specialises in creating the best value air scrubbers for large and complex scenarios. You can contact us with any questions you may have about air scrubbers. We will be happy to answer them for you.