Dichromate method is a common method to determine chemical oxyen demand,which is also the stipulated method in state standard GB11914-89,but the calculation of its uncertainty was never reported.

• 重铬酸钾法测定化学需氧量是常用的测定化学需氧量的方法,也是国家标准GB11914-89中规定的方法,但对该方法的不确定度的计算尚未见报道。