This European Standard specifies a method for the determination of nitrogen in soil improvers and growing media. The Kjeldahl method determines ammonium-N, nitrate-N, nitrite-N and organic N content of soil improvers and growing media. Nitrogen in N-N-linkages, N-O-linkages and some heterocyclics (especially pyridine) is only partially determined. , , 
The method is not applicable to liming materials and preformed materials such as mineral wool slabs and foam slabs.
NOTE The requirements of the standard may differ from the national legal requirements for the declaration of the products concerned.
90.93 Standard confirmed
Oct 3, 2017