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Analysis of air and precipitation

NILU can look back on decades of experience with sampling and analysis of different components in air and precipitation. We detect both inorganic ions, gases and metals, and Persistent organic pollutants (POPs) and polycyclic aromatic hydrocarbons (PAH). NILU analyses also a range of different components through the national air monitoring programme.

Analysis of air samples

NILU can detect different gases in air. For analysis of air samples are used both, active and passive samplers.

Active samplers

These samplers include a filter that is impregnated with chemicals to catch gases such as nitric acid (HNO3), Sulphur dioxide (SO2) and ammonia (NH3). It is covered with another filter without impregnation to filter particles. The particle filter will be analysed for anions and cations in air, additionally also heavy metals can be detected.

Passive samplers

Passive samplers are a simple and cheap measuring method. The customers can place them themselves based on instructions from NILU.

The passive sampler contains an impregnated filter to detect the gas that shall be analysed.

NILU can offer passive samplers for the following compounds:

  • Nitrogen dioxide (NO2)
  • Sulphur dioxide (SO2)
  • Ammonia (NH3)
  • Acetic acid and formic acid (on the same filter)
  • Nitric acid (HNO3)
  • Ozone (O3)
  • Nitrogen oxides (NOx)

Analysis of precipitation

NILU has long experience with sampling and analysing of different compounds in precipitation. We analyse both pH, conductivity, anions, cations and metals in precipitation. We use suitable collectors to collect precipitation samples.

National air quality monitoring

Through a number of years, NILU has analysed and detected quantities of particles in air deposited on filters as part of air quality monitoring from our background stations, urban observations and around industrial sites.

We use quartz filters to detect both quantities of dust, heavy metals and EC/OC (elementary carbon and organic carbon).

We can detect amounts of dust in size fractions of PM2,5 and PM10.

This is carried out in a special clean chamber with relative humidity between 45 and 48% and ca 21,5C temperature.

The national environmental monitoring is divided into three main programs, with one of them being environmental compounds:

Reference laboratory

NILU is a National Air Quality Reference Laboratory. This requires high demands regarding precision.