Abstract:

Objective To establish an optimal detection method for nitrogen dioxide（NO₂） using a portable pump suction-type gas detector，providing assistance for emergency detection，daily monitoring and other work. Methods Worksite sampling and laboratory analysis were conducted simultaneously using both the national standard method and the portable pump suction-type detector. The two methods were compared to evaluate the applicability of the direct-reading detection method in workplace air toxicity detection. Results Under standard conditions，the portable detector achieved a minimum detection limit of 0.05 mg/m³ and a quantitation limit of 0.20 mg/m³. The method exhibited high accuracy and precision within the concentration range of 0.20-32.71 mg/m³.Under varying temperature，humidity，and interference conditions，the accuracy ranged from 98.79% to 100.69%.Compared to the national standard method，the relative deviation between the two methods was 0.90%-5.40%. Conclusion Compared with the national standard method，the portable direct-reading method demonstrates superiority in sensitivity，convenience，speed，and accuracy，making it a viable alternative for the detection of NO₂ concentration in the workplace air.

Key words: Workplace, Nitrogen dioxide（NO₂）, Portable, Pump suction-type, Direct-reading detection, Toxic substance detection in the air