Ppm is an acronym for Parts Per Million. 1 ppm is equivalent to one drop of water diluted into 50 litres (roughly the fuel tank capacity of a compact car) or 1 mm in 1 km.
How to visualize one part per million:
What is ppb?
With our new high-resolution platform (HPP), you will also find the unit "ppb". Ppb is an acronym for Parts Per Billion. To give you an idea of the ppb resolution: measuring a single drop of a different liquid in an Olympic size swimming pool, or 1 mm in 1,000 kilometres. But let us do it in the air!