The uncertainty evaluation of the formaldehyde

• 1、Number One Station of Quality Supervision and Inspection of Beijing City as Qulity Controller

Abstract：The formaldehyde content in leather was detected with spectrophotometer. The uncertainty of this analytical process was evaluated in the paper. By evaluation we know that the uncertainty was originated from the following several aspects, a) the C0 determination process, b) the extracted liquid volume, c) the sample quality, d) the repeated determination of sample. The uncertainty of C0 determination included the uncertainty of calibration curve fitting and the uncertainty of the standard series of solution prepared. And the uncertainty of standard series of solution prepared process included the uncertainty of standard solution and stored solution diluted process. The uncertainty of calibration curve fitting was calculated with the Bessel formula. The uncertainty of standard series of solution, extracted liquid volume and sample quality were calculated with the data provided by certificate of standard substance and the repeated detection data. The uncertainty of repeated determination was the standard deviation of the six repeated standard deviation. By evaluation results we can see that the main component of the uncertainty came from the C0 determination, namely came from the uncertainty of calibration curve fitting and the standard series of solution prepared. In order to minish the total uncertainty, we can increase the working curve points and use standard solution with lower concentration to reduce the dilution progression.

Keywords： uncertainty spectrophotometer formaldehyde content calibration curve fitting standard series of solution prepared