Research on the correlation between the toxicity of a petrol engine and the vehicle mileage

The research paper presents the results of the analysis of exhaust gases from vehicles with a gasoline engine, equipped with a neutralization system, and a vehicle without a neutralization system. At the time of the test, the vehicles had operating time from 3 to 300 thousand km on the mileage. An INFRAKAR 5M3T gas analyzer was used for the analysis of gases. It is shown that for vehicles with high mileage, higher values of the content in the exhaust gases are observed NOx, CO and CH. The exception was the CO data obtained for the engine not equipped with an exhaust gas aftertreatment system. It was found that the measurement errors are identical limits of permissible relative error recorded by the INFRAKAR 5M3T gas analyzer concentrations of CO, CH and NOx. It is shown that the presented set of values CO, CH, NOx are not described by the normal distribution of random numbers. Rank correlation was used to assess the relationship between the content of toxic substances in the exhaust gases and vehicle mileage. The maximum value of the Spearman rank correlation coefficient was 0.80. Correlation coefficients are not statistically significant. © 2025 Elsevier B.V., All rights reserved.