# Impact of Environmental Factors on Passenger Ride Comfort
## 1 Introduction  
Ride comfort is one of the key issues in assessing the quality of transport services, particularly in the context of increasing passenger expectations for both public transport and individual transport. The perception of comfort is influenced by a wide range of factors that affect the passenger during the journey, from environmental parameters to factors related to the design and equipment of the vehicle. Comfort levels are also influenced by physical factors. Simultaneous consideration of these diverse factors becomes crucial in assessing comfort, as different environmental stimuli, such as noise, vibration, lighting, and temperature, can affect passengers' sensations differently.  
These factors vary significantly between modes of transport. For instance, metro systems and city trains often experience higher vibration levels compared to cars, while buses may expose passengers to fluctuating temperatures due to frequent stops and open doors. Noise levels are typically higher on trains and buses than in cars due to their structural design and operational environment (e.g., metro in tunnel).  
A deep understanding of environmental factors that affect ride comfort is crucial because they directly impact passengers' well-being and satisfaction. This knowledge may be helpful in optimising vehicle design to reduce discomfort, such as incorporating better suspension systems or noise insulation. Moreover, it can serve an informational role, particularly in urban transport planning, by informing policy-making authorities to prioritise investments in modes of transport that offer better comfort or improve existing systems. This approach can not only enhance the travel experience but also encourage the use of public transport, contributing to sustainability goals.  
Contemporary research on ride comfort includes a variety of approaches, ranging from subjective (survey) studies to quantitative analyses based on measurements of selectedphysical parameters in real operating conditions. Most studies focus on investigating vibrational comfort, not only because it is a primary factor but also due to its relatively straightforward measurement process. The aim of this paper is to comprehensively assess passenger ride comfort in selected modes of transport, using the author's research method based on a synthetic comfort index that takes into account the influence of various relevant physical factors. This study focuses on a comparison of ride comfort in a passenger car and in metro trains--new and older types.  
This article describes and discusses the research methodology in detail. Section 2 takes a closer look at the issue of ride comfort, discussing the factors that affect passenger perceptions, including environmental aspects and individual traveller characteristics. Section 4 focuses on the measurement methodology, where the evaluation criteria adopted, the equipment and test procedures used, and the scale according to which the different types of comfort were classified are presented. The Section 7 contains the results of the experimental studies, presenting the levels of vibrational, acoustic, thermal and visual comfort for different modes of transport and operating conditions. The Section 8 summarises the results, pointing out the most important findings, including areas in need of upgrading to improve comfort and potential directions for further research into comprehensive passenger transport comfort assessment.