Calculating upper control limits for exposure point concentration of formaldehyde content in textiles by non-parametric method

To break through the limitation of sample amount in calculating the upper control limits for exposure point concentration of formaldehyde content in textiles by parametric method,a non-parametric method,Bootstrap resampling method was introduced to simulate the sampling process based on the testing data of formaldehyde of textile samples collected randomly in domestic market to generate a mass of simulation dataset.Upper control limit for exposure point concentration of formaldehyde(95%UCL) was calculated based on this bootstrap resampling dataset and got a result of 52.73 mg/kg by this method.This method can be used in wide range,even in the conditions of non-normality of data distribution and limitation of sample amounts.