Measuring indoor air quality

September 20, 2023 by
JoTio Tech s.r.o., Andrea Jonášová

Indoor air quality has a direct impact on human health. At low levels, the presence of certain substances only results in increased fatigue, but high concentrations are dangerous to health.

In modern times, people spend most of their time indoors, whether at home, at school or at work. Many people do not realise that indoor air is often polluted and unhealthy. Just breathing and the evaporation of volatile compounds (VOCs) from materials inside a building can cause poor air quality. In the home, common activities such as cooking, cleaning, drying laundry or lighting candles contribute to the formation of pollutants. This turns an improperly ventilated space into a health hazard that leads to fatigue, headaches, lack of concentration, allergies, asthma and, in worse cases, cancer.

What should be monitored?

Temperature

Measuring the temperature and setting it to the optimum value helps to create the right conditions indoors. It not only has a significant impact on human health, comfort and productivity, but also helps to reduce the rate of VOC evaporation.

Humidity

Humidity is another important factor affecting air quality, and too high humidity is just as harmful as too low humidity. Indoor humidity varies according to the season, but should generally be between 30% and 70%. Optimum humidity also prevents the spread of bacteria and the spread of disease. High indoor humidity creates conditions for mould growth, which is a source of allergic reactions and respiratory diseases. Conversely, low humidity compromises the respiratory system and immunity.

Barometric pressure

Barometric pressure varies depending on meteorological conditions. Its fluctuations can affect the human body. Sensitive individuals may experience headaches, fatigue or nervousness, which can affect a person's well-being and performance.

TVOC

Volatile Organic Compounds (VOC) are chemicals that are released spontaneously from solid materials. These substances change from a solid to a gas at room temperature. Some of the most common substances in the air are acetone, benzene, toluene, nitric oxide, formaldehyde, hydrogen sulphide, etc. The TVOC then expresses the total concentration of these substances. High concentrations of TVOC cause eye, nose and respiratory irritation, nausea, allergic reactions, chronic respiratory diseases, etc.​

Carbon dioxide (CO2)​

Carbon dioxide is released into the air by humans, pets and, at night, plants. Higher concentrations can be particularly dangerous for people with respiratory problems. The maximum recommended indoor CO2 level is 1,200 - 1,500 ppm. Higher concentrations cause fatigue, headaches and decreased concentration. Levels above 5,000 ppm cause nausea, breathing difficulties and even loss of consciousness at levels above 40,000 ppm.​ 

PM

Particulate Matter (dust) is airborne microparticles that pollute the air. It is divided into three size categories, PM1 (≤ 1 µm), PM2.5 (≤ 2.5 µm) and PM10 (≤ 10 µm). PM10 consists, for example, of particles of metals, sulphates, soot or inorganic salts that are released from any friction surfaces. The particles bind volatile organic compounds (VOCs), enter the human body and can cause respiratory diseases and infections and cancer.

Formaldehyde (HCHO)

Formaldehyde is one of the most dangerous mutagenic and carcinogenic substances found indoors. It is used in the manufacture of paints, varnishes, adhesives and stains and so often becomes a component of furniture, flooring, wallpaper or cleaning products from which it is gradually released. At concentrations of less than 1 mg/m3 it causes respiratory irritation, at higher concentrations it causes pneumonia, brain, kidney and liver damage and at levels of 60-125 mg/m3 it can even cause death.

Ozone (O3)

Although essential for life, ozone is one of the most toxic gases in the air. Its inhalation causes health problems at concentrations as low as 0.3 ppm, while it is commonly found in nature below 0.125 ppm. The effects of elevated ozone concentrations and inhalation include respiratory problems, coughing, sore and dry throat, eye irritation, and aggravation of chronic respiratory or heart disease.

Increased concentrations of hazardous substances will eventually dissipate. The problem is that in many buildings there is not enough ventilation and harmful substances gradually concentrate.

When to ventilate?​

A wireless air quality detector alerts you when it's time to open the window. The device measures substances in the air at three levels. The first level shows that the air is fine and the second level gives a warning when the measured values are close to critical levels. If these values are exceeded, the third level is triggered by an audible signal, a negative emoji on the display and an alert notification to the mobile phone.


There are several types of sensors available in our e-shop, differing, among other things, in the range of detected substances. The following table shows an overview of the different sensors and their ability to measure different parameters.



Asperiot: AM319


Asperiot: AM308


Asperiot: AM307

Asperiot: AM103 
/
Asperiot: AM103L

Temperature

YES

YES

YES

YES

Humadity

YES

YES

YES

YES

CO2

YES

YES

YES

YES

Motion

YES

YES

YES

-

Light

YES

YES

YES

-

TVOC

YES

YES

YES

-

Barometric pressure

YES

YES

YES

-

PM2,5; PM10

YES

YES

-

-

Formaldehyde

YES*

-

-

-

Ozone

YES*

-

-

-

*Alternative options are the HCHO or O3 sensor, both of which support interchange.


Not sure which sensor is ideal for your needs? Feel free to contact us and we'll be happy to help you choose.

Resources:

KVALITA OVZDUŠÍ V UZAVŘENÝCH MÍSTNOSTECH [online]. [cit. 2023-09-22]. Dostupné z: https://obchod.hw.cz/clanky/