All about Air pollutions, Xiaomi air Purifiers and Filters

Haze has been an ongoing problem in many countries in the Southeast Asia region, and Malaysia is one of the worst affected. The haze crisis grips the region nearly every year during the dry season, when agricultural land is illegally cleared by burning in Indonesia. During the haze period Malaysian skies will be a smoky grey for most of the months.

Get the latest API (Air Pollutant Index) readings from official site –

How does that affect our health?

First, we need to know some facts that most of us may not be aware of, even we are unconsciously every few seconds of our lives.

As the air that we breathe is almost invisible to us, we may not be aware of the ubiquitous killer that had threatened the health of our families, for both in-door and out-door air.

There are various threats present in the air that we breathe.

Where are air purifiers deployed?

We spend majority of our times in-door

Quality air purifiers have never been more important for good health. The tight seals that make your home comfortable and energy efficient also trap indoor air pollution. From cooking fumes and cleaning vapors to dust and pet dander, there is a wide variety of vapors and particles that pollute indoor air. Statistics from the Center for Disease Control (CDC) and Environmental Protection Agency (EPA) have shown that the air inside your home can be five to ten times dirtier than the air outside, and more importantly, Americans spend an average of 90% of their lives indoors.

Since we spend so much time inside, it is important for us to learn how to reduce or eliminate this dangerous chemical from our homes.

Type of filters

Different air purifier filters target different types of air pollution, and what they target depends almost exclusively on the type of filtration technology they employ. HEPA air purifiers are the most popular, and they are perfect for eliminating household allergens such as dust, animal dander, pollen, and other particulate. They are not very good at capturing ultra-fine particles like viruses or eliminating foul odors, organic compounds, smoke, or chemical fumes. Because different air purifier technologies have different strengths and weaknesses, many modern air purifiers combine two or more filter or media types in the same unit. 

The Xiaomi standard filter filter utilizes a HEPA filter along with a thick bed of activated carbon to help eliminate dust, pollen, and dander as well as things like smoke, odors, and chemical vapors.

  • HEPA (High Efficiency Particulate Air) Filters set the standard for air purification. By definition, a HEPA filter removes at least 99.97% of all particles as small as 0.3 microns.HEPA filters allow only very small particles to pass through them. Allergens such as pollen, animal dander, mold spores, and dust get trapped in the filter. The main disadvantage of the HEPA air purifier is that you have to periodically change the filter. The main advantage: if it is HEPA certified, then you know it works well for all common particle allergens. However, not all HEPA filters are created equal. Size matters: the more square feet of HEPA filter, the more particulate it will be able to remove. The size, material, and construction of the actual filter media all play a role in the air purifier’s performance and may account for why one HEPA filter is more expensive than another.
  • Activated Carbon Filters are rarely used alone to purify the air, but they are often used in conjunction with other filters. Activated carbon/charcoal filters excel at adsorbing odors and gases and neutralizing smoke, chemicals, and fumes. When carbon is treated with oxygen, it opens up millions of pores. There are so many of these tiny pores and fissures that one pound of activated carbon has a surface area of 60 to 150 acres. This huge surface area makes it ideal for adsorbing gases and odors, providing an enormous surface area for potential bonding with chemical/vapor molecules. The larger the carbon filter, the more chemicals it will be able to absorb and the longer it will keep on working. When it’s full, when it can adsorb no more chemical molecules, it has to be replaced. 

Among the 3 different types of Xiaomi air purifier filters, they are generally available as:

a) The green Standard Edition is ship as default filter with the generation 1 purifier, and is available separately as add-on items;

b) The blue Particulate Removal Edition is ship as default filter with the generation 2 purifier, and is also available separately as add-on-items;

c) The Formaldehyde Edition is sold separately as single item, and is not included as default filter in Gen 1 or Gen 2 purifiers;

Air Purifier Air Exchanges  

Most quality air purifiers operate efficiently and quietly in a one room environment. To be effective, an air purifier must have a motor and fan powerful enough to properly circulate air throughout the space. Once the air is pulled into the unit, it is filtered through various types of filter media, and clean air is released back into the one room environment to start the cycle all over again. The amount of time it takes an air purifier to cycle through all of the air in a room is referred to as an “air exchange.”

The more air exchanges per hour (ACH), the better air quality in the room. The number of air exchanges is determined by two things: the cubic feet (volume) of a room and the cubic foot per minute (CFM) output of the air purifier. All air purifier manufacturers list airflow ratings (in CFM) for each fan setting at which their machine operates. Ideally, you want to set a goal of 4 to 6 air exchanges per hour. There is no such thing as overkill when talking about air exchanges.

Proper Placement of an Air Purifier  

As a general rule, it is more difficult to filter the air in a large and open space, and this is mainly due to inadequate air circulation. Large living rooms and family areas, especially those with abnormally high ceilings, present a challenge to effective air filtration. Our rule with larger rooms is to attempt to direct the purified air exhaust from the air purifier to the vicinity of the rooms inhabitants. Inside a room, be sure to keep adequate space around the air purifier, typically 18″ or more. Most units intake air from multiple sides, and restricting this by placing the air purifier against a wall or piece of furniture will reduce efficiency.

In the bedroom, place the unit 6-10 feet from the headboard of the bed with the directional registers pointing at the bed. This is often far enough away to avoid feeling a draft but close enough that cleaned air is reaching you.

Most air purifier manufacturers implement a bottom to top airflow, meaning the air is pulled into the machine at the bottom and released towards the top.

Xiaomi Air Purifiers – Gen 1 and Gen 2 comparisons

Xiaomi Air Purifiers – Gen 1 and Gen 2 comparisons

Mi air purifier 2 is launched on November 24, 2015, it can be considered as the upgrade generation of the earlier Generation 1. Compared to the Gen 1 model, the biggest change was undoubtedly in its volume on a smaller foot-print, but also less space occupied. Mi air purifier Gen 2 is targeted mainly for small apartment users which can provide for purification area of 23-48 m².

Xiaomi has made the Air Purifier 2 lighter as well as smaller. As compared to the 735×260 mm laterally size Air Purifier 1, the Air Purifier 2 measures simply 520×240 mm.

The foot print area is also 15% smaller.

It houses a solitary electric motor, twin booster fans (which detoxifies at an effective variety of up to 39.6m²), The design of the Mi Air Purifier 2 was inspired by aircraft engines and comes with an anti-formaldehyde enhanced filter that’s replaceable. It also filters 99.99% of PM 2.5 particles and up to 92% of formaldehyde (a colorless, flammable, strong-smelling chemical that is used in building materials and to produce many household products).

Xiaomi says the more compact design is made possible by a new single-motor, dual-fan design, which has enabled it to shrink its dimensions by up to 40 percent over its predecessor. However, its smaller size means that Air Purifier 2 has had to take a slight performance hit compared to the predecessor’s dual-motor design. Its Clean Air Delivery Rate (CADR), or the amount of air it cleans per minute, is now 330m³/h in standard mode, compared to the 406m³/h for the larger model.

Still, this can go up to 388m³/h in Turbo mode and Xiaomi says it can filter the air in a 23m² room in only 10 minutes.

In addition to the smaller foot-print compared to Gen-1, some optimization was also done to the motor, dual-fan blower motor design in Gen-1 is now reduced to single fan motor in Gen-2, this also allowed energy saving of 58% compared to Gen-2.

The above chart shows the different recommended room areas for different CADR value, so that air can be purified efficiently by the air purifier.

Although smaller in size, and the motor going through some optimization and changes, but its purifying effect does not seem to lowered, the one-hour PM2.5 purification can reach 97.7%.

In the purification capacity, CADR is now 330 m³ per hour for standard mode, and in the turbo mode CADR is 388 m³ per hour, clean up area from 27.2 – 46.6 m² (292 – 500 ft²), it takes 10 minutes to complete a purification process once for a 23 m² (250 ft²) room.The firm additionally urges that the Air Purifier 2 is substantially more power efficient – 58 percent even more power efficient.

The company states that the newly improved device is now 11 percent quieter than in the first generation AP, and also makes merely 30db of noise when switched over to sleep mode.

The indicator LED is placed at 7.5cm from the ground, just to low enough to avoid the light interference when reading on the sofa or resting in bed.  The light sensor can be adjusted according to the indoor light LED brightness, the indicator can also be completely off.

Mi air purifier 2 is an intelligent air purifier with a WiFi connection to the phone, you can use Mi Smart Home App for live view of indoor air quality changes at home and will base on bedroom area to adjust according to the most appropriate mode of operation. It is smart enough to learn the user’s habits, such as automatically adjusted to sleep mode before you go to sleep, and  to automatically shut down when they go out.

New Addition – Control of new smart phone temperature, humidity sensor

Mi Air Purifier 2 had added the high quality Japan SHINYEI sensor, which provide real-time detection of indoor air PM2.5 content. The Air Purifier will change according to the data for air quality, and automatically switches to the optimum decontamination mode. In addition, AP2 also adds temperature, humidity sensors, which will provide mobile phone view on indoor air quality, temperature and humidity changes at a glance, helping you to always grasp the comfort of the indoor environment.

Coming to the mechanism, the Air Purifier 2 packs a quality Tri-filters: Pre-filter, HEPA filter and an Activated Carbon filter that comes with a filtering capability of whooping 99.7% of PM 2.5

Comparing the official specifications

Dimensions : First Generation is taller, second generation is smaller in size, the filter is common use for both generations.

Purification efficiency: First generation has better purification performance than 2nd generation, and with larger decontamination area as well.

Smart Module: Both generation 1 & 2 have WiFi module and air quality sensors, 2nd generation has added multi temperature and humidity sensors.

Power: First generation has maximum power consumption of 75W, 2nd generation has maximum power consumption of 31W.

Package Contents: Both generations has the same content, while the packaging size of 1st generation is much bigger, due to the taller size of the Air Purifieritself.

Purifier functions: Both generations have automatic mode, sleep mode, the switching mode switching, WiFi indicator, air quality indicator, particulate matter sensor, the difference is first generation has light sensor and Turbo mode, and the second generation has the Favorite mode.

Smart phone remote control functions: Both generations can be accessed through Smart phones for remote control functions, the second generation has a new temperature and humidity testing and comfort assessment functions.

Xiaomi Air Purifiers – Gen 1 and Gen 2 comparisons