Air: counting ultrafine particles is added
From 12 December 2026 air must be tested not only for dust mass but also for particle number and size distribution. In areas with high concentrations, ultrafine particle supersites will be set up — at least one per five million inhabitants.
- The new air quality directive has been in force since 10 December 2024 and, besides tightening the limit values, it changes the way measurement is done — weighing dust stops being enough.
- By 12 December 2026 the number of particles and their size distribution must be measured, not just the mass of dust in a cubic metre of air.
- The finest particles weigh almost nothing, so a mass measurement does not see them — and it is those particles that penetrate deepest.
- In areas with high concentrations, supersites for ultrafine particles are to be set up, at least one per five million inhabitants.
- These are points with an extended range of determinations, measuring continuously.
- The measurement is to follow standard EN 16976: a defined way of sampling, preparing the air sample and counting the particles, not any counting device at hand.
- For laboratories testing air this means new equipment and a new item in accreditation scopes, alongside the classic determinations of suspended dust and its composition.
Source: EUR-Lex