Photometric determination of nitrite. • Photometric determination with sulphanilic acid and 1-naphthylamine. • In acidic solution sulphanilic acid is diazotised with nitrite. The diazonium salt is coupled with 1-naphthylamine to form a red dye. • Type: standard test 1-67. • Range: 10 mm cuvette: 0.01 - 0.30 mg/l NO2-N / 0.10 - 1.00 mg/l NO2- ; 50 mm cuvette: 0.002 - 0.100 NO2-N / 0.005 - 0.250 NO2- • Sufficient for: 220 determinations. • Sea water suitability: yes