An air purifier has become a staple in most households.
These devices comes in all shapes and sizes. When you start researching air purifiers, you’ll come across many acronyms and terms related to air purifiers you’ve never heard before. Also, it is pretty confusing, especially which one really does matter.
Don’t worry! I will explain all of the acronyms and terms in a way that you’ll easily understand.
In less than 10 minutes, you will get a bigger perspective on consumer air purifiers.
Air Purifier Acronyms & Terms
Here’s the list of the air purifier acronyms and terms in alphabetic order. Jump straight to the acronym or term by clicking an item on the list.
- Activated Carbon
- Air Purifier vs. Air Cleaner
- dB and dBA
- Efficiency vs. Effectiveness
- ESP – Electrostatic Precipitator
- MCS – Multiple Chemical Sensitivity
- Ultrafine Particles
- UV Light
- VOCs – Volatile Organic Compounds
1. Activated Carbon
Activated carbon or activated charcoal is a material used in air filters that traps gases and odorous elements from the air. They are made of coal, wood, or nutshells through a heating process. This is how they become ‘activated’ or ‘porous’ and able to adsorb pollution.
You will find 2 types of activated carbon filters in air purifiers:
- Granular Activated Carbon Filter: In the form of grains or pellets in the filter. This type is the most common in mid-range air purifiers. Normally, the activated carbon grains or pellets are encased in a honeycomb-shaped frame.
- Impregnated Activated Carbon Filter: A flimsy foam or sponge type filter impregnated with activated carbon. This type of filter also acts as a pre-filter to block larger particles. Basically, budget air purifiers have this type of activated carbon filter.
ProTip: Granular activated carbon filters are better. Large amounts of activated carbon are necessary for deep cleaning (gases, chemicals, and VOCs).
Adsorbent materials are used in air purifier filters to remove gases and odorous pollutants. The widely-used adsorbent media is the activated carbon. In some air purifiers, you will find zeolite, activated alumina, potassium iodide, and other earth minerals.
Association of Home Appliance Manufacturers. They test and rate air-cleaning devices for the ability to remove tobacco smoke, dust, and pollen from an enclosed room. The higher the number, the faster the air purifier cleans the air.
ProTip: AHAM-verified seal will give you some extra trust in an air purifier.
ACH (Air Changes per Hour) refers to how many times an air purifier exchanges the whole air in a room in an hour.
The rate is relevant only with the room size and the air delivery rate (variable with fan speed setting). When you see an ACH quoted, you need to know the size of the room and the air delivery rate used to make the calculation.
Do your personalized calculations for an air purifier in your room using our ACH Calculator. You only need two things to calculate: the air purifier’s air delivery rate (normally for the max fan speed setting) and your room dimensions.
ProTip: The higher the ACH number, the faster the air cleaning will be.
5. Air Purifier vs. Air Cleaner
Air Purifiers are also known as Air Cleaners. Technically, there are no differences. Some manufacturers and websites use the term ‘Air Cleaner’ when referring to their products.
The terms are interchangeable.
You might be familiar with allergens. These are biological or chemical substances, most often natural, that cause people to have allergic reactions. Examples of allergens are pet dander, pollen, fungal spores, and dust.
The air purifier’s primary job is to remove these airborne allergens.
CADR (Clean Air Delivery Rate) is a metric for measuring an air purifier’s performance. It represents the amount of filtered air delivered by the air purifier within a certain time.
The metric is presented as cubic feet per minute (CFM). They can also be represented as cubic meters per hour (m³/h). This is the measurement of a unit’s performance as a complete system, and the higher the number, the more air is cleaned in less time.
ProTip: CADR is one of the most important metrics to buy an air purifier. Calculate the required CADR for your room for effective cleaning using our CADR Calculator.
In California, for an air-cleaning device to be sold, it must need CARB approval for ozone safety. CARB categorizes air purifiers as mechanical (only use physical filters) and electronic (has at least one electronic filter).
Each category has its own set of specifications that have to be met. For an electronic air purifier, the ozone emission limit is 0.050 parts per million or 50 ppb.
ProTip: If the air purifier is electronic or has any electronic filter add-ons such as an ionizer, ensure the purifier is CARB-approved.
9. dB and dBA
The abbreviation for decibel. Decibels measure the relative loudness of sounds. The higher the number of decibels, the louder the sounds.
When measuring sound, dB is used for general purposes. However, dBA or dB(a) is used only for the sound that human ears can hear. Because you probably know, we can’t hear all sound frequencies (our range is about 20 Hz to 20 kHz).
Normally, a medium-sized air purifier generates 30 to 50 dBA of noise. To understand, a whisper is 30 dBA, and it is 60 dBA for an air conditioner.
ProTip: EPA recommended safe sound level for indoor activities is 45 dBA.
10. Efficiency vs. Effectiveness
An air purifier’s efficiency is the measure of its performance in a lab test. It determines how much pollutants it can remove after the air passes through its filter(s) at once. It’s sometimes called “single-pass” efficiency.
For example, a HEPA filter can remove 99.97% of particles with a size of 0.3 microns from the air on each pass.
On the other hand, “Effectiveness” is the real-world performance. In most cases, it depends on the fan speed setting (airflow rate), the location of the air purifier in the room, and usage hours.
ProTip: Locate the air purifier at the center of your room, elevate it a bit from the floor, and keep your doors and windows closed. More useful tips to get effective results.
11. ESP – Electrostatic Precipitator
An air-cleaning technology that requires electricity. Using electricity, it charges airborne particles through an electrostatic process that becomes attracted to oppositely charged plates. They then stick to the plates.
Learn more about the air cleaning technologies of air purifiers.
“High-Efficiency Particulate Air” filter. HEPA filters are extended-surface (pleated many times) media filters. They require no electricity to function. HEPA filters are a popular option when it comes to air purifiers.
Not all HEPA filters are created the same, and they have many different classes. Some of the most common are listed below to help you understand them a bit more.
- H13 HEPA: A higher-grade HEPA filter removes all 0.21 microns or larger particles at a 99.95% efficiency.
- True HEPA: Standard HEPA filter traps 99.97% of particles that are 0.3 microns or larger. The standard is set by the U.S. Department of Energy (DOE).
- H12 HEPA: Consumer-grade HEPA filter removes all particles 0.3 microns or larger at up to 95% efficiency.
- HEPA-type or HEPA-like: These filters are less effective at trapping particles and are only rated for particles 2.5 microns or larger with 95 to 99% efficiency.
ProTip: When purchasing an air purifier, get one with a True HEPA, or Higher-grade HEPA filter makes a big difference.
Indoor Air Quality. This term refers to the air quality in and around buildings. It specifically has to do with the health and comfort of the people in or around the building.
Indoor air quality mostly depends on the ventilation, indoor pollution sources, temperatures, and humidity in a building.
An air-cleaning technology that releases negative ions, stick with airborne particles, and brings them down. This way, they silently settle dust.
You will find Ionizer as an add-on in many consumer air purifiers. They boost the air filtration rate slightly.
ProTip: A small amount of ozone is emitted during the ionization process. Don’t use the function if you have any breathing issues or use it for pets, babies, or the elderly.
15. MCS – Multiple Chemical Sensitivity
A syndrome that people may suffer from having to do with symptoms from chemical exposure.
The symptoms can include headache, fatigue, dizziness, breathing difficulties, and others.
A gas-phase filter air purifier might help to combat MCS since they can remove some chemicals, gases, and VOCs from the air.
Ozone is an atmospheric gas. The ozone layer protects us from the harmful cosmic UV rays.
But the gas is not safe to inhale. Many electronic air-cleaning devices emitted ozone as a byproduct. Try to avoid them. At least make sure the device is CARB-approved.
Also, ozone gas can be used for air cleaning purposes in unoccupied areas, known as Ozone Generators.
A particle is a small mass of a solid or a liquid present in the air. Most airborne particles are considered pollutants.
Particles are also referred to as Particulate Matter (PM). They fall into 3 major categories according to their sizes:
- PM1: Particles with a diameter of 1 micron and smaller. These are very dangerous as they can be inhaled deep into the lungs and penetrate the bloodstream. Traffic emissions, fly ash, bacteria are around PM1 in size.
- PM2.5: Fine inhalable particles that are 2.5 microns in diameter and smaller. Some common PM2.5 pollutants are household dust, pet dander, and mold spore.
- PM10: Inhalable particles that are 10 microns or less in diameter. Examples are pollen, cement dust, etc.
To understand the scale, the average thickness of human hair is about 70 microns (µm).
18. Ultrafine Particles
Ultrafine particles (PM0.1) are any particles that measure less than 0.1 microns across. Tobacco smoke and viruses are some examples of ultrafine particles.
19. UV Light
A form of radiation not visible to the human eye. Ultraviolet light is part of the electromagnetic spectrum and has a wavelength of 10 nm to 400 nm. There are three different types of ultraviolet light:
- UV-A: “Long-wave” UV radiation measuring 315 to 400 nm.
- UV-B: “Medium-wave” UV radiation measuring 280 to 315 nm.
- UV-C: “Short-wave” UV radiation measuring 100 to 280 nm.
UV light air purifiers use high-energy UV-C light to disinfect the filter. It has the ability to kill mold, bacteria, and viruses.
ProTip: When buying an air purifier with UV lights, go with the high-power UV bulbs option instead of the less effective UV LEDs.
20. VOCs – Volatile Organic Compounds
VOCs or Volatile Organic Compounds are organic compounds that are emitted from solids or liquids. Many of them have short-term or long-term health effects. VOCs typically have concentrations up to ten times higher indoors than they do outdoors. There are plenty of household products that are known to emit VOCs, some of which are listed below:
- Paints and paint strippers
- Aerosol products
- Insect repellents
- Automotive products
Because VOCs are so common, there have been many labels and warnings created by the EPA related to their danger.
ProTip: An adsorbent media filter air purifier might help to reduce the VOCs concentrations from the air.
When you’re looking to purchase an air purifier, plenty of complicated terms come with them. Understanding them is the best way to ensure that the air purifier you’re purchasing is high-quality. Be sure to keep these terms handy when you’re looking for your next air purifier, and know what air quality issues you might be facing.
That way, you’ll know exactly what to buy!