The purpose of this study is to develop correction formulas using the results of measurement by PMS 103, which is a weight method measuring device, and by Dusttrak (TSI, USA), DustMate (Turnkey Instrument Ltd., UK), and LD-5 (SIBATA, Japan), which are light scattering measuring devices. The objective is to evaluate and identify new standards (to develop a proposal) in order to complement the limitations of the existing measurement methods of public transportation vehicle indoor air quality by utilizing the three nephelometer type measuring devices. In the case of non-rush hours, the PMS values were estimated using an estimation regression equation. Statistically, the PMS values that were actually measured were not significantly different (p-value=0.4375, 0.4375, 1.000). With respect to the agreement between the two values, ICC was 0.99 in the case of the estimation regression equation using LD-5 values, 0.97 in the case of the estimation regression equation using Dusttrak values, and 0.84 in the case of the estimation regression equation using DustMate values to allow for the identification of agreement at greater levels. In the case of rush hours, the PMS values were estimated using an estimation regression equation. Statistically, the PMS values that were actually measured were not significantly different (p-value=0.3125, 0.6250, 0.8125). With respect to the agreement between the two values, ICC was 0.92 in the case of the estimation regression equation using LD-5 values, 0.91 in the case of the estimation regression equation using Dusttrak values, and 0.89 in the case of the estimation regression equation using DustMate values to allow for the identification of agreement at greater levels.