[Microbial contamination of railroad trains].

The bacterial contamination of the air was studied in moving rail road trains. The air in front of the trains is poor in microorganisms. The contamination increases to the end of the train which is caused by the dust which is whirled up by the air stream from the rail substructure and the depletions from the toilets. The bacteria which had grown in a culture suspension, appeared in the air around the train when they have been poured to the toilets. The colony count decreases with the distance of the point of contamination. The prevention of contamination is mainly a economical problem but it can be solved in the future.