# Impact of Environmental Factors on Passenger Ride Comfort
## 3 Motivation and Purpose
However, a small number of studies have considered more than one factor affecting passenger ride comfort, and most often, these studies have been extended to include the impact of noise. Examples of work where mechanical vibration and noise levels were considered simultaneously are papers [18; 19], where the authors, respectively, investigated the ride comfort in passenger combustion cars in different driving scenarios and compared the level of comfort in combustion and electric cars. Another example is the work in [20], where the same factors were studied in multiple rail electric units. Moreover, a study was conducted to explore the relationship between the vibration dose and the equivalent noise level affecting passengers on metro trains [21]. It should also be noted that researchers refer to different recommendations for acceptable noise levels, often based on local authority regulations. The current state of the literature includes few works that consider a larger group of environmental factors. One study that considered air temperature in addition to vibration and noise is [22], with its important part being an assessment of the combined effect of these factors on passengers' sensation of thermal comfort. Another of the few studies taking into account a wide range of comfort factors, such as vibration, pressure changes, noise, and temperature, is reported in [23]. In the cited work, the authors also take into account subjective factors, such as the availability of catering services and information services or the appearance of the interior. Existing evaluation methods for ride comfort have their strengths and limitations. For instance, vibration-based assessments provide valuable insights into mechanical discomfort but fail to address the broader sensory experience of passengers. On the other hand, subjective methods, such as passenger surveys, offer a more comprehensive view of comfort but often lack the objectivity required for technical analysis. So far, the present authors have investigated rail vehicle dynamics [24] to determine passenger comfort resulting from the effects of vibrations [25]. To account for the complexity of ride comfort and its increasing importance in rail transport, the authors recently extended their investigations by including the results of measurements of additional factors [26]. That paper aimed to address a gap in the existing body of research by considering multiple environmental factors affecting passenger comfort, rather than focusing on a single factor such as mechanical vibrations. However, there is a growing need for comprehensive assessments that incorporate multiple factors, such as noise, temperature, and even lighting. The aim of this study is to further develop such a multi-factor approach and, in particular, to propose a method for the comprehensive assessment of ride comfort by taking into account the physical environmental factors relevant to the passenger. By including a broader range of factors, this research seeks to contribute to a more accurate and complete understanding of ride comfort across different transport modes, hopefully providing valuable insights for both transport operators and policy makers.