Fine particles (PM stands for “Particulate Matter”) are tiny solid particles or liquid droplets suspended in the air. Some of these particles are quite large and visible to the naked eye, such as smoke, soot or ash. The smallest of them, often invisible, penetrate deep into our bodies and can affect our respiratory and blood systems.

So how can we improve Indoor Air Quality?

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Published on 6 November 2023

Farewell to fine particle pollution: how to improve Indoor Air Quality?

In this article:

Fine particles (PM): what are they?

Often emitted by combustion processes or chemical reactions, they are harmful to health. Fine particle levels are measured in micrograms per cubic metre (µg/m³). These pollutants come from incomplete combustion associated with domestic and industrial activities, as well as road traffic. They can also be of natural origin, due to soil erosion, biomass fires, pollen, etc.

Unlike dust, which is larger, fine particles are so microscopic that they are invisible to the naked eye. They are also called “suspended particles” because they travel through the environment.

These particle rates are divided into three categories:

  • PM1: ultrafine particles with a diameter of less than 1 micrometre;
  • PM2.5: fine particles with a diameter of less than 2.5 micrometers;
  • PM10: with a diameter of less than 10 micrometers, i.e. 100 times smaller than a millimeter.

For example, a grain of fine beach sand is around 90 micrometers. In the environment, depending on the source, these fine particles reduce air quality.

What are the sources of this environmental pollution?

Fine particles can originate from natural sources, such as volcanic eruptions. Human activity also emits them via :

  • Industrial emissions such as smoke and dust
  • Urban transport with exhaust fumes from combustion engines
  • Intensive farming
  • Heating appliances burning wood, oil or coal in buildings
  • Household activities such as cooking, renovations, the use of paint and cleaning products, cigarette smoke and so on.

Contrary to popular belief, they don’t just accumulate on the outside. They can come from inside a dwelling. Some of this breathed-in pollution may come from an external source that penetrates to the interior. Many factors can release pollutants into the home and affect air quality. Cooking, lighting candles, using poorly-maintained heating appliances or chimneys can all increase particulate emissions.

These dusts can also come from biological sources such as mold, dust or pet dander. These kinds of particles can trigger allergies. In a house, levels can vary depending on the type of ventilation or filtration. The concentration of these pollutants differs from indoors to outdoors.

The quantity of fine particles produced depends on their source, environmental conditions and the quality of the technologies used to control these emissions. Individuals can contract various illnesses after inhaling large quantities of these particles.

How do they affect health?

Every year in France, almost 40,000 deaths and 8 months of life expectancy are lost as a result of exposure to fine particles. In Europe, by 2020, no fewer than 238,000 premature deaths will be caused by exposure to these pollutants. According to theWorld Health Organization (WHO), around 7 million people die every year from these airborne particles.

The presence of this dust is a health hazard. Once inhaled, PM1 and PM2.5 present the greatest risks. These dusts penetrate deep into the respiratory tract and even the bloodstream. Both categories of fine particles affect the lungs and heart.

Victims of air pollution may experience a variety of symptoms:

  • Irritation of areas around eyes, nose, throat and ears
  • Itchy eyes, sneezing and runny nose
  • Asthma and allergy triggers
  • Provocation of mood and cognitive disorders
  • Triggering heart attacks, strokes and lung cancer

This environmental pollution can affect people throughout their lives. Children and the elderly are the most vulnerable to these effects. Circulating particles can be detected using fine particle detectors.

How can we limit particle levels in buildings?

To determine whether a home is polluted, it is possible to install fine particle sensors such as those from Nexele.

A fine particle measurement device is equipped with a specific sensor capable of measuring PM1, PM2.5 and PM10 concentrations.

To limit this pollution, you can make a few changes to your daily routine:

  • Installing air purifiers
  • Change vacuum cleaner bags regularly
  • Inspect and clean appliances frequently
  • Chimney sweeping and maintenance of boilers and heaters
  • Clean your home using products that emit no pollutants
  • Ventilate regularly
  • Ventilation for interior renovation work

These small, everyday gestures will go a long way towards reducing the level of particulate matter in the home. In France, to limit air pollution, the installation of a fine-particle sensor is not mandatory, but recommended.

Fine particles can have serious consequences for human health, making them an important Indoor Air Quality (IAQ) issue. It is useful to identify the sources of these particles in the home, so that corrective measures can be taken to safeguard the health of occupants. Implementing these actions will considerably limit the impact on indoor air quality.