关键词: 室内空气品质, 气态污染物, 测定方法, 影响因素, 改进措施

Abstract:

The problem of excessive concentrations of indoor gaseous pollutants such as formaldehyde and benzene, which pose a threat to human health, is becoming increasingly serious. To achieve efficient indoor air purification, it is necessary to first determine the characteristics of each pollutant. Current studies often use the strategy of a single standard method for the determination of a pollutant (e.g., sulfur dioxide using spectrophotometry) and improve the precision of the determination by adding sample pre-treatment and adjusting the composition of the absorbing solution. However, due to limitations in the principles of different measurement methods (e.g., spectrophotometry relying entirely on changes in absorbance of the sample) and the complexity and variability of indoor environments (e.g., the coexistence of multiple pollutants or special high-temperature and high humidity environments), it is usually difficult to accurately measure a wide range of concentrations by a single standard method. Furthermore, there is often a significant discrepancy between the results of the different methods, which makes it challenging to compare the results of different methods and to provide an accurate basis for air purification. This paper aimed to address this problem by summarizing five commonly used methods for measuring indoor gaseous pollutants and analyzing their corresponding advantages and disadvantages. ① The spectrophotometric method was simple and accurate. It had a wide range of applications, but its stability was poor. ② The chromatography method was efficient and sensitive. It had low interference but required high operational skills. ③ The sensor method was portable and easy to read, but its repeatability was poor. ④ The standardized methods such as chemiluminescence can achieve real-time detection with a wide linear range, but they had poor anti-interference ability. ⑤ The new measurement methods represented by electronic noses could achieve rapid detection, but its operation was complex and the cost was high. Meanwhile, this article summarized and analyzed various impact factors in the measurement process, and found that temperature and the measurement process were the main error sources. For example, the accelerated reaction between gaseous pollutants and reagents at high temperatures resulted to incomplete color rendering, and non-standard operation by testing personnel could lead to inaccurate test results. This article provided an overview of the determination methods applicable to indoor gaseous pollutants with different characteristics. It also outlined the advantages and disadvantages of each method, as well as the detection limits/quantification limits and applicable scenarios. Furthermore, specific influencing factors and corresponding improvement measures were provided at the operational level of determination, which could serve as valuable references for selecting appropriate determination methods and improving the accuracy of indoor gaseous pollutant measurement.

Key words: indoor air quality, gaseous pollutant, detection method, impact factor, improvement measure