VOCs Occupational Exposure Assessment And Engineering Improvement In The Workplace

The single component of chemicals is targeted to perform the occupational exposure assessment traditionally.In research laboratory used various chemicals,it is difficult to apply the specific exposure limit to perform the occupational exposure assessment.Also,the strategy of the engineering improvement is hard to be developed practically based on the authorized occupational exposure limit;The term of the volatile organic compounds(VOCs)is applied into the occupational exposure assessment in the pilot area of the plastic application,in masking line in the semi-conduction industry,in the aluminum or sliver-aluminum printing line in the photovoltaic industry,in the quenching and painting line in auto spare parts industry,in the coating line in mechanical equipment industry.The concentration of VOCs is monitored in the workplaces via the portable instrument(PID)and the internal exposure limit(IEL)is identified after the overall data statistic.The root cause failure analysis is performed to identify the strategy of the engineering improvement to impair the exposure of the volatile organic compound in the pilot area of the plastic application.It is shown that the 95th percentile concentration of VOCs in seven reference workplaces is 1.09mg/m3,7.03mg/m3,2.42mg/m3,2.62mg/m3,0.96mg/m3,0.03mg/m3,7.14mg/m3 in sequence.The VOCs concentration in semi-conductor workplace and in mechanical equipment industry workplace is higher than the value in photovoltaic workplace and in auto spare parts industry workplace.The maximum exposure in the reference workplace is 4.356mg,28.002mg,9.664mg,27.858mg,10.208mg,0.355mg,22.892mg.0%-18%percent of exposure results from skin absorption,the median is 4.6%;and 82.0%-100%percent results from respiratory,the median is 95.4%.For working out the ventilation improvement in plastic processing pilot area,the eleven failure causes are identified,including five engineering design failures,four for management measures,two for people awareness.Consequently,the 25th percentile of VOCs concentration in the reference workplace is regarded as the performance metrics of ventilation improvement,it is 0.96 mg/m3,and regarded as internal exposure limit in plastic processing pilot area as well.In consideration of the internal exposure limit,the ventilation improvement plans are developed.