GB 16202-1996 Hygienic standard for chloroprene in workshop air GB16202-1996 Standard download and decompression password: www.bzxz.net
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National Standard of the People's Republic of China Health standard for chloroprene in the air for workplace Subject content and scope of application This standard specifies the maximum allowable concentration of chloroprene and its monitoring and inspection methods. This standard applies to all types of enterprises that produce chloroprene and use chloroprene and its products. 2 Hygiene requirements The maximum allowable concentration of chloroprene in the air of the workplace is 4mg/m (skin), monitoring and inspection methods The monitoring and inspection methods of this standard adopt gas chromatography, see Appendix A (supplement). 4 Supervision and implementation Health administrative departments at all levels are responsible for supervising the implementation of this standard. Approved by the State Administration of Technical Supervision on April 3, 1996 132 GB16202--1996 Implementation on September 1, 1996 A1 Principle GB 16202-1996 Appendix A Gas chromatography (Supplement) Chloroprene in air is separated by di-nosedioic acid ester and detected by hydrogen flame ionization detector. The retention time is used for qualitative analysis and the peak height is used for quantitative analysis. The detection limit of this method is 1×104ug (direct injection of 1mL air sample). The determination range is between 0.32 and 20mg/m2, the attenuation multiple does not change, and the linearity is good. A2 Instrument Syringe: 100 mL, 1 mL. Micro syringe: 1μL. Gas chromatograph: hydrogen ionization detector, the signal-to-noise ratio of 0.32ng chloroprene is not less than 5:1. A3 Reagents A3.1 Chloroprene (2-chloroprene-1,3), chromatographic grade. A3.2 Sebacate, chromatographic stationary liquid. A3.36201 support: 60-80 mesh. A4 Sampling Take a 100mL syringe, purge it with on-site air three times at the sampling site, then draw 100mL of air, put on a rubber cap, and place the syringe vertically. Complete the analysis in the shortest possible time, no more than 24 hours. A5 Analysis steps A5.1 Chromatographic conditions Chromatographic column: column length 2m, inner diameter 4mm, stainless steel column, sebacate: 6201 support = 10:100, column temperature: 110℃; a. b. Vaporization chamber temperature: 160℃, Detection chamber temperature: 150℃; Carrier gas (nitrogen): 50mL/min. A5.2 Standard curve drawing Use a micro syringe to take a certain amount of chloroprene (at 20℃, 1μL chloroprene weighs 0.9583mg), inject it into a 100mL syringe, and prepare a standard gas of a certain concentration. Take a certain amount of chloroprene standard gas, dilute it with clean air to 0.001, 0.002, 0.004, 0.01μg/ml chloroprene standard gas, take 1mL of sample respectively, and measure the retention time and peak height. Repeat each concentration 3 times, take the average value of the peak height, and draw a standard curve by plotting the content of chloroprene against the peak height. Retention time is a qualitative indicator. A5.3 Sample analysisbZxz.net Take 1ml of air sample and inject it directly (record temperature and pressure), use retention time for qualitative analysis and peak height for quantitative analysis. A6 Calculation A6.1 Convert the injection volume into the volume under standard conditions according to formula (A1). V. =V× 273 + t . (A1) GB16202--1996 Where. V. …Sample volume under standard conditions, mL; V -sample volume, mL; —temperature, °C; pAtmospheric pressure, kPa. A6.2 Calculate the concentration of chloroprene X according to formula (A2) Where: X-concentration of chloroprene in air, mg/m2; V. Sample volume under standard conditions, mL; C × 1 000 The content of chloroprene in the sample found on the standard curve, ug. A7 Notes (A2) Acetylene, vinyl chloride, benzene, chlorobenzene, 3,4-dichlorobutene, cis- and trans-1,4-difluorobutene coexisting at the sampling site can be completely separated from chloroprene by retention time under the conditions of this method, and will not interfere with the determination of chloroprene. Additional notes: This standard was proposed by the Ministry of Health of the People's Republic of China. This standard was drafted by the School of Public Health of West China University of Medical Sciences. The main drafters of this standard were Li Shouqi and Dong Qinan. This standard was first issued in 1979 and revised in 1996. This standard is interpreted by the Institute of Labor Hygiene and Occupational Diseases, Chinese Academy of Preventive Medicine, which is the technical management unit entrusted by the Ministry of Health. 131 Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.