Assessment of vehicle-induced acoustic and vibrational impacts on the human body

Environmental noise and mechanical vibrations generated during vehicle operation represent important factors influencing passenger comfort and human health. With the rapid development of modern transport systems and the increasing time individuals spend in vehicle environments, the assessment of acoustic and vibrational conditions inside vehicle cabins has become an essential research topic in transport engineering. Prolonged exposure to elevated levels of noise and vibration may lead to physiological and psychological discomfort, reduced concentration, fatigue, and other adverse effects on the human body. The present study investigates the acoustic and vibrational characteristics occurring inside vehicles and evaluates their combined influence on passengers. An experimental analysis was carried out on a passenger bus of category M3, with a capacity of 51+1 seats. Measurements of interior noise levels were performed under stationary and dynamic operating conditions using a Class 1 sound level meter with A-weighting and specialized data acquisition software. The experimental results demonstrated that the average interior noise levels were 44.81 dB(A) at 600 rpm, 55.34 dB(A) at 1500 rpm, and 57.05 dB(A) at 2000 rpm, while the measured noise level during vehicle motion at 45 km/h reached 56.51 dB(A). The obtained results indicate that variations in operating conditions significantly influence the acoustic environment inside the passenger compartment. Based on the analysis of experimental data and existing scientific literature, a comprehensive evaluation of the combined effects of noise and vibration on the human body was conducted using the concept of cumulative exposure or “pollution dose”. Furthermore, the study discusses engineering approaches and technical solutions aimed at reducing acoustic and vibrational loads in vehicle cabins. The findings of this research contribute to a better understanding of noise and vibration interactions in vehicle environments and may serve as a basis for the development of effective strategies to improve passenger comfort and reduce harmful acoustic and vibrational exposure in modern transport systems.