Unpleasant smells often come from trains while they are running, mainly due to poor maintenance and sanitation issues. One major cause is the clogging of sewage pipelines, which leads to the accumulation of waste and foul odor spreading throughout the coaches. In many cases, human waste leaks or flows out of the train’s holding tanks, creating both hygiene and environmental concerns. Another common problem is the jamming of sinks, which happens when passengers dispose of paper soap residues and leftover food items improperly. This blockage prevents proper drainage, causing dirty water to flow back and sometimes spill onto the floor, moving toward passenger areas and increasing discomfort. The lack of regular inspection and timely repairs worsens these issues.