Last updated: April 15, 2026
Spring is often associated with freshness and nature coming back to life. However, there is one issue that is not talked about enough: air in Lithuania during April is often far more polluted than it appears at first glance.
At this time of year, the air contains a mix of pollen, street dust, fine particulate matter (PM2.5), construction dust and even Saharan dust carried from Africa. All of this doesn’t just stay outdoors — it also enters your home. And the first place it ends up is your MVHR system and its MVHR filters.
If filter replacement was delayed after winter, April becomes the month when your system may start working against you rather than for you.
What Is in the Air in Lithuania During April?
1. Pollen Boom
In spring, large amounts of pollen are released into the air — not only from birch trees, but also from other flowering trees, shrubs and plants. Some particles are larger, but others — especially in humid or windy conditions — can break down into much finer particles that enter the respiratory system more easily. This is particularly relevant for people with allergies.
2. Street Dust and PM10 Spikes
After winter, large amounts of fine dust, soot, road salt residues and other pollutants accumulate on streets. As roads dry in spring, wind and passing vehicles lift these particles back into the air. This is why PM10 levels often spike during spring, particularly in cities and near busy roads. These particles irritate the eyes, nose and throat and affect overall wellbeing.
3. PM2.5 – The Particles You Can’t See
Even more dangerous are PM2.5 particles, which are small enough to reach deep into the lungs. In Europe, they are not only produced by traffic or combustion, but also by agricultural activity. For example, ammonia released into the air reacts with other substances and forms secondary fine particles. The European Environment Agency clearly states that agricultural ammonia emissions significantly contribute to this problem.
4. Saharan Dust
Yes — this is not a myth. In spring, Saharan dust regularly travels across Europe and can even reach Lithuania. It increases the concentration of airborne particles and can reduce air quality even on sunny, seemingly “clean” days. These events are recorded across Europe and their impact is very real.
5. Construction and Seasonal Cleaning Activities
April marks the start of outdoor cleaning, street sweeping, renovation and construction work. This adds yet another layer of dust into the air. If you live near construction sites, gravel roads or heavily maintained areas, your MVHR filters will become contaminated much faster than usual.
Why Is This Dangerous for the Air in Your Home?
Many people assume that indoor air is automatically cleaner than outdoor air. Unfortunately, this is not always true. According to the EPA, indoor air can in some cases be 2–5 times more polluted than outdoor air, and people spend around 90% of their time indoors.
So, if your MVHR system is running with filters already contaminated after winter, something simple happens: it no longer protects your home as effectively as it should.
Common Signs That It’s Time to Replace Your Filters
- The air at home feels heavier
- Cooking or bathroom odours linger longer
- Bedrooms feel stuffy in the morning
- Allergy symptoms worsen
- The MVHR system becomes noisier
- Electricity bills increase
And it’s not just about comfort. Contaminated MVHR filters increase system resistance, which can reduce airflow, increase fan load and lower the overall efficiency of ventilation. Poor air exchange leads to higher CO₂ levels, increased humidity and reduced system performance.
What Should You Do Now?
If you haven’t replaced your filters after winter, April is one of the most important months to do so. This is especially important if:
- You live in a city
- There are allergy sufferers or children in your home
- There is construction nearby
- You feel the need to open windows more often to get fresh air
An MVHR system can significantly improve your indoor air quality — but only when it operates with clean and properly selected filters.
If you are looking for filters suitable for your unit, “Filtrų pasaulis” makes it easy to find the right MVHR filters and replace them on time. In spring, this is not a minor detail — it directly affects the air you breathe every single day.
