There is almost no risk of the indoor climate becoming polluted. A full 80 % of the micro particles in the air fall to the bottom of the ventilation window unit on the inside. These particles can be removed using a vacuum cleaner.

Force Technology Denmark produced a report based on measurements of ventilation windows installed at Vesterbrogade in Copenhagen, an urban location where concentrations of micro particles in the air are high.

The report confirms that the ventilation window has effective self-filtering properties.