NECi`s enzyme based nitrate determination method is ASTM International Standard Method D7781. It replaces Test Methods D1254 (nitrite) and D992 (nitrate). This method is applicable to the determination of nitrate plus nitrite (as nitrogen) in drinking water, surface, saline, wastewater, and ground waters (ASTM Scope 1.1). This method may be purchased here. The Nitrate Elimination Co, Inc, develops and manufactures enzyme-based products for water testing. Our recombinant nitrate reductase enzymes, test kits, and reagent packs enable nitrate determination in any sample type.