GB 16202-1996 Hygienic standard for chloroprene in workshop air

GB 16202-1996 Hygienic standard for chloroprene in workshop air GB16202-1996 Standard download and decompression password: www.bzxz.net

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 analysiswww.bzxz.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
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
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