| Formaldehyde is a bioplasm poison, whose toxicity is relatively high and potentially carcinogenic. As one of the main indoor airborne contaminations it is more and more recognized high in importance of detection. Our national Criterion of Indoor Air Quality prescribe that there are two kinds of national standard methods to analyze formaldehyde, spectrophotometry and gas chromatography. What is characteristic of the two methods is that they both require collecting gas specimen first then analyzing them at laboratory. The disadvantages include that the analytic period is long, the cost is high, the manipulative process is intricate, and the results can not reflect the situation of indoor formaldehyde pollution real time and fill the needs of monitoring numerous sites.What make it good to use formaldehyde detector are its convenient transportation, easy handling, celerity, delicacy, real time analysis, etc. But at present, there is lack of a thorough study on all sorts of speedy-mensuration formaldehyde detectors as to its response performance, influence of conditions, error, uncertainty, the relativity with national standard, etc. Thus leading to its inconvenience in practical application. This paper is developed to the question. We select the formaldehyde detector model INTERSCAN4160 from America, which is typical of its kind, and produce formaldehyde gas using dynamic gas-generation equipment to give a detailed study of formaldehyde detector analyzing formaldehyde. Its performances are tested. The influences of various conditions are compared and the best operation conditions are ascertained. The patulous uncertainty of the technique is determined. Comparisonbetween the speedy mensuration and national standard method at laboratory and on the spot were done. Based on the work mentioned above we established a speedy and easy-handling mensuration which is fit for detecting the concentrations of indoor formaldehyde on the spot.The correlation coefficient of the regression equation of the speedy mensuration is above 0.999 and has notable significance. The measure range is from 0.02ppm to 19.99ppm. The delicacy is 0.01ppm. When examining the methodology we chose three characteristic concentration values which are one, two and five multiples of the sanitarian standard respectively. Each of the concentration values are measured six times. The variability of repetition is below 5.6 percent. The relative error is under 1.8 percent. The average relative standard deviation of the three concentration values is 4.9 percent. The patulous uncertainty of this methodology is under 10 percent. Compared with national standard GB/T 18204.26-2000, namely hydroxybenzene reagent spectrophotometry, the "t-test" between data obtained using the speedy mensuration and their counterpart using spectrophotometry shows no marked difference, and the reliability is 95 percent.Study shows the speedy-measuration and the portable formaldehyde detector 4160 has the merits of light and handy, facility, fast, reliable and giving results real time etc. The established speedy mensuration is provided with canonical operation regulations and calibration measure. The results of analysis are comparable to those of existing national standard favorably. In this way an authoritative and valid formaldehyde mensuration which is both fast and on the spot is ensured. The outcome of the study provide the authority with gist to constitute unitive technique guide line and measure for speedy analysis of indoor airborne formaldehyde, and help to find out in-depth rule of indoor formaldehyde pollution, consequently impose a significance on monitoring indoor formaldehyde contamination.
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