Samples (9 kg) consisting of mixts. contg. the corn. dusty salpetre or reagent-grade NH(4)NO(3), NH(3) (4.6 to 23% by mass) an explosive and an elec. detonator were field tested for explosivity in open or closed vessels under atm. pressure or under pressure up to 40 atm and at temp. up to 90 degrees C. An explosion took place only in the case of samples with low NH(3) content (below 13%) or treated at 90 degrees C under pressure 9 atm. The samples of a comps. typical for the industrial NH(3) absorption in Divers liqs. (NH(3)-satd. aq. soln. of NH(4)NO(3)) were sate in operation.