Photometric determination of BOD5. • Tube test for the determination of the biochemical oxygen demand in 5 days (BOD5) by using the diluting principle according to the German Standard Method DIN 38409-H51. The incubation of the samples is carried out in Winkler oxygen flasks. The determination of oxygen dissolved in water at day 0 and after 5 days is carried out similarly to the Winkler Method DIN EN 25813-G21 by photometric evaluation of iodine-colour. • Type: Tube test 8-25. • Range: 2 - 3000 mg/l O2. • Sufficient for: 22 determinations. • Sea water suitability: yes.