Why must subway cars in passenger service during winter be kept heated between 40 and 65 degrees?

Maintaining the temperature of subway cars between 40 and 65 degrees during winter is primarily for passenger comfort. Riders typically dress for outdoor conditions, and the interior of the subway cars must provide a warm environment that contrasts with the cold outside. A comfortable temperature ensures that passengers can travel without experiencing discomfort from cold temperatures, which can lead to negative feelings about the service and discourage ridership. While there are other factors involved in train operation, like machinery performance and track conditions, the key focus here is on providing a pleasant experience for passengers, aligning their needs with the standard service expectations.