Development and evaluation of ozone detection paper

A high sensitive paper with good response has been developed for ambient ozone monitoring. The paper operates by employing the reaction of ozone with indigo carmine. This reaction results in white-yellowish reaction products on the paper that can be determined by measuring the paper’s reflectance. Direct, on-site measurements are possible because of the selection of the color change reaction, and only a small photoelectric meter is needed. The combination of a cellulose sheet, humectant, acid and indigo carmine is needed to achieve a good response and the color of our developed ozone detection paper fades completely from blue to white when exposed to ozone concentrations of about 400 ppb × h. The humectant content strongly affects the ozone response, and a 20% glycerol content of the immersed solution yields the best response. We also measured the effects of temperature, relative humidity and wind speed on the ozone response, and found that relative humidity has a strong influence on the ozone response. The interference gases were checked for six chemicals that are usually present in the air, and only hydrogen peroxide exhibited positive interference. Since our developed sensing paper has the good response, it is suitable for hourly to daily mean measurements of ambient ozone and we successfully measured indoor ozone concentrations using our developed ozone detection paper and a photoelectric meter with a single wavelength source.