ISO DIS 20236

Description / Abstract: This document specifies a method for the determination of total organic carbon (TOC), dissolved organic carbon (DOC), for the determination of dissolved and particular bound nitrogen (TN_b) and dissolved bound nitrogen (DN_b) in the form of free ammonia, ammonium, nitrite, nitrate and organic compounds capable of conversion to nitrogen oxides under the conditions described. The procedure is carried out instrumentally.

NOTE Generally the method can be applied for the determination of total carbon (TC) and total inorganic carbon (TIC) (see Annex A).

The method is applicable for water samples (e.g. drinking water, raw water, ground water, surface water, sea water or waste water).

The method allows a determination of TOC/DOC ≥ 1 mg/l and TN_b/DN_b ≥ 1 mg/l. The upper working range is restricted by instrument dependant conditions (e.g. injection volume). Higher concentrations may be determined after appropriate dilution of the sample.

Cyanide, cyanate and particles of elemental carbon (soot), when present in the sample, can be determined together with the organic carbon.

Volatile (VOC) or purgeable organic carbon, or dissolved nitrogen gas (N₂) are not determined under the conditions described by this method.