ABSTRACT
OBJECTIVE: To establish a method of determination of difluorochloromethane in workplace air by direct sampling gas chromatography. METHODS: Difluorochloromethane in workplace air was collected with aluminum plastic composite film airbag and then directly injected. Difluorochloromethane was separated by DB-1 capillary column and detected with hydrogen flame ionization detector. RESULTS: Good linearity was obtained in the range of 1.50-15 042.90 mg/m~3 with the correlation coefficient of 0.999 96. The limit of detection was 1.26 mg/m~3 and the limit of quantitation was 3.78 mg/m~3. The minimum detection concentration was 1.26 mg/m~3 and the minimum quantification concentration was 3.78 mg/m~3. The standard recovery was 98.34%-99.19%. The within-run relative standard deviation(RSD) and the between-run RSD were 1.82%-3.72% and 2.17%-4.17%, respectively. The samples can be stored at room temperature for at least 7 days. CONCLUSION: This method is suitable for difluorochloromethane detection in workplace air.