1. Scope of Application
This standard specifies the dichromate method for determining the chemical oxygen demand in water. This standard is applicable to the determination of chemical oxygen demand in surface water, domestic sewage, and industrial wastewater. This standard is not applicable to the determination of chemical oxygen demand in water with a mass concentration of chloride greater than 1000 mg/L (diluted). When the sampling volume is 10.0 ml, the detection limit of this method is 4 mgL and the lower limit of determination is 16 mgL. The upper limit for undiluted water samples is 700
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