Assessment on uncertainty in determination of hydrogen peroxide in disinfectant

[Objective]To discuss the main influencing factors of uncertainty in determination of hydrogen peroxide in disinfectant.[Methods]A mathematics model was established according to the measurement method, and the uncertainty components were calculated and analyzed. [Results]The concentration of hydrogen peroxide in disinfectant was 32.2 g/L and the expanded uncertainty was 0.29 g/L. The relative standard uncertainty of whole determination process was 0.004 8. The relative uncertainty of consuming titrant volume in measuring sample was 0.002 8,that of repeated measurement was 0.002 4,and that of inhaling sample with 10 ml transfer pipette was 0.001 9.[Conclusion]The uncertainty component of consuming titrant volume in measuring sample accounts largest proportion on uncertainty of measurement. The operation should be standardized to ensure the reliability of measurement results.