Update on Standard Methods and ASTM Efforts to Create New Total Nitrogen Methods

Oral Presentation

Prepared by W. Lipps
Shimadzu Scientific Instruments Inc., 7102 Riverwood Drive, Columbia, MD, 21046, United States

Contact Information: [email protected]; 410-910-0802


Wastewater permit and ambient water testing for total nitrogen most often requires a TKN test and a nitrate plus nitrite test that are summed to provide a total nitrogen value. There are several interferences with the TKN digestion method including dissolved solids and high nitrate. In fact, although TKN includes organic nitrogen and ammonia, it is not uncommon for ammonia results to be higher than TKN. ASTM and Standard Methods are both developing new methods for total nitrogen analysis. These methods replace TKN with safer, greener options and reduce complexity by measuring TN directly.