3 Technologies to Measure Particulate Matter

In this article we will analyze all the available Technologies to Measure Particulate Matter such as PM1, PM2.5 and PM10. This article is trying to answer which type of technology is better and how they work.

First: The Laser Diffraction

Many companies use this kind of technology for their PM sensor like IQAir-AirVisual, Xiaomi, Dylos, Kaiterra-LaserEgg etc. With this technology the sensor is able to figure out the size of the particles and the quantity. This technology is also known as Optical Light Scattering because each time a particle passes and hits the laser beam then an optical sensor, like a camera’s sensor, and with the help of an algorithm will translate how many particles were in the air at that moment. This technology is very stable and the sensor can take measurements fast, typically between 3-10 seconds.

One of the problems that the laser diffraction technology has is how each pollutant is determined by the sensor. For example Black Carbon BC which is an absolute black colored pollutant will absorb some of the light from the laser beam, so it doesn’t react the same as will do a white colored particle which will reflect more light. This problem can be solved with the right algorithm but again the device won’t be able to use the right algorithm for the right pollutant unless we told it which one to use.

Second: The Infrared

The infrared technology is common in less expensive indoor AQ monitors like Foobot, Awair etc. Basic the sensor is a small chamber with two holes on opposite directions which allow the air to pass through. An infrared light is crossing the air there and an infrared sensor is able to determine the light intensiveness. Dimmer light means that pollution is passing through the holes.

One of the problems that the infrared technology has is the estimation of the particles, this technology can’t count particles, it is just guessing. There could be 1200 PM2.5 particles or 300 PM10 particles or 1 gram of sand, either way the infrared sensor will give the same measurement.

Third: The β Beta Attenuation Mass

The β Beta Attenuation Mass technology or BAM is as big and expensive as the length of its name and very uncommon to be found in an indoor environment. Governmental bodies use this kind of instrument like in UK, China etc. Basically, it samples air on a blank piece of filter paper. Then the trapped PM pollution on the paper will be bombarded with some beta radiation. Some of the PM2.5 pollutants absorb the radiation, and the differences on the other side are measured. After that, some mathematical equations are used to determine how the weakening of the β rays translates into a mass of PM2.5. Attenuation is a general term that refers to any reduction in the strength of a signal and in this case the β radiation. The BAM technology is far more accurate than the other two technologies.

There are some disadvantages with this technology too. Humidity can affect the results so proper calibration is always needed.

Some general info to have in mind that applies to all three technologies. If you have two units of the same technology side-by-side, you will still get small variations in results even between 2 BAM monitors. That’s simply because particles in air, especially PM10, aren’t necessarily uniformly dispersed.


Cars vs People and the future

I had a conversations a few weeks ago about cars and what should we do as a society. Should we abandon them or should we find a better alternative? So I thought sharing my personal opinion and of course I would love to read some comments.

Although it is a matter of opinion, automobiles were invented in 1886 by Karl Benz. Immediately people loved the idea that they can move around easily and fast. Since then not much have changed, cars still are burning fossil fuels to move but one thing has happened, the advertisement reinforced the way people feel about cars.

Every good advertiser knows that if he/she wants to make a successful advertisement he/she has to focus on the feeling of the audience to make a successful sell. Today cars offer self-esteem and status to the people and it is wide acceptable that a person with a car, especially a fast and expensive car, worth more than a person who rides a bike. Let’s pay attention on a car ad the next time we watch TV. They present the driver as the most powerful person in the world with success in love life and in businesses. Of course there isn’t only one ad with the same message, it seems that all the companies and all the models inject the same message and all of them are bombarding the subcontinent of a person over and over. For a long time they have washed our minds.

It is so hard to compete with that, it is hard to raise awareness that most cars are bad for the environment and for our health. It is hard to make people think twice that the smoke exiting from a car is a bad by-product of the vehicle. Regulation and concern is needed.

The reason I am writing this article is because in my conversation with the people who already know how bad cars are for the society and want to ban them completely, it made me think that this is practically impossible. Although they are right, I believe that this is utopian and unaffectable. The advertisement has done a significant damage in the society and it will be almost impossible to undo the mind-shaping people have suffered over the years. The car makers will never stop promoting the cars as necessity.

The best alternative in my opinion is to move to green energy (solar-wind) sources and invest on good quality electric vehicles that they will last a long time on the roads.

I don’t own a car but I would like to make a comment about how people interact with cars. For example parents are very protective with their kids, so most of them won’t ride their kids to school on a cold rainy day but they will drive them in a car without thinking twice if they should or not. Of course they could take the bus, but let’s be real here, people have learnt in convenience and the majority of them will choose to drive to school over taking the bus even if it was an electric bus.


We have to move forward and adopt as soon as possible greener energy and transportation. Governments and companies need to understand that we don’t live only for today and future generations have the right to live on a sustainable environment.


Psych Study: When You’re Bummed, You’re More Likely to Buy