This International Standard specifies a method for the determination of the total organic nitrogen, as well as any
ammoniacal nitrogen, present in photographic processing wastes by the Kjeldahl method.
Total Kjeldahl nitrogen can be determined in photographic processing wastes in the range of 10 mg/l to 200 mg/l as
ammonia, or in the range of 8 mg/l to 160 mg/l in terms of nitrogen. If ammoniacal nitrogen (see ISO 6853) is
determined separately and subtracted, the concentration of organic amino nitrogen can be established.
WITHDRAWN
ISO 6851:1987
PUBLISHED
ISO 6851:2001
90.93
Standard confirmed
Jun 6, 2026