The instrument is a modified version of the elemental analysis coupled to a gas isotope ratio mass spectrometer (IRMS). The modified elemental analysis allows stable isotope measurements and elemental content determinations of solid samples in the range:

2.5-12 µg nitrogen content with a standard deviation ð¹⁵N von 0,2-0,3‰

5-120 µg carbon content with a standard deviation ð¹³C von 0,15-0,25‰

0.2-1.5µg sulphur content with a standard deviation ð³⁴S von 0,25-0,35‰

The solid samples are placed in small tin containers. Measurements of filter samples (GF or quartz filters) are also possible. (see sample preparation)

CN or simultaneous CNS isotope measurements are performed.

A patent application has been filed for this method.