The standard applies to all types of water and to water-soluble substances. Dis urbances due to the presence of reducing substances (including sulphites, sulphide and iron(II)) in the sample can be eliminated by treating the sample with oxygen in a closed bottle. Dis urbances due to the presence of oxidizing substances (including chlorine and hydrogen peroxide) in the sample can be remedied by adding equivalent amounts of sodium sulfite.
NEN 6512-1984 history
1984NEN 6512-1984 Water - Determination of acute toxicity in aerobic active sludge by measurement of the respiration rate