Level of comfort and safety in railway transit

Canada's railway industry has invested more than $20 billion since 1999 to improve the safety of users as a top priority. Although the accident rates have decreased, the users' safety and comfort could still be impacted by vehicle's vibration, air quality, and noise levels. In this regard, comfort and safety are mutually related aspects; worsening of air quality could compromise users' safety from a respiratory health perspective. Further, noise, level of lighting, thermal condition and movement could contribute to hearing problems, visual impairments, bacteria growth, and nausea, respectively. Management of urban transit systems should ensure a convenient transit service with adequate levels of ride and quality (time and cost) as well as users' comfort and safety. This article proposes an approach for measurement of riders' comfort (as it relates to safety) in terms of humidity, temperature, vibration, concentration of CO2, noise, and lighting level based on a set of maximum thresholds identified with respect to public health guidelines. This enables the use of a weighting method to establish an overall network comfort level. Such an index can be used to direct the allocation of investments for improvement of comfort as well as ridership. A case study of several lines in Sydney trains network is presented to illustrate the applicability and usefulness of the proposed approach. Data were collected and analyzed using low-cost technologies such as smart phones and mobile sensors. The comfort factors are measured and reported per train line and then combined to generate an overall comfort index.