ISO/TR 11905-2:1997

Water quality - Determination of nitrogen - Part 2: Determination of bound nitrogen, after combustion and oxidation to nitrogen dioxide, chemiluminescence detection

This Technical Report specifies a method for the determination of nitrogen present in water in the form of free ammonia, ammonium, nitrite, nitrate and organic compounds capable of conversion to nitrogen dioxide under the oxidative conditions described. Determination is carried out instrumentally using chemiluminescence detection. Dissolved nitrogen gas is not determined by this method.

This method is applicable to the analysis of natural freshwater, sea water, drinking water, surface water, waste water and treated sewage effluent.

The concentration range of the method will depend on the injection volume used, which is instrument specific. Nitrogen can be determined in the range up to 200 mg/l. Higher concentrations can, if necessary, be determined by dilution of the sample.

The limit of detection will depend on the instrument used. Using a suitable injection volume, the limit of detection is typically 0,5 mg/l.