The　risk　of　COVID-19　infection　has　increased　due　to　the　prolonged　duration　of　travel　and　frequent　close　interactions　due　to　popularization　of　railway　transportations.　This　study　utilized　depth　detection　devices　to　analyze　the　close　contact　behaviors　of　passengers　in　high-speed　train　(HST),　traditional　trains　(TT),　waiting　area　in　waiting　room　(WWR),　and　ticket　check　area　in　waiting　room　(CWR).　A　multi-route　COVID-19　transmission　model　was　developed　to　assess　the　risk　of　virus　exposure　in　these　scenarios　under　various　non-pharmaceutical　interventions.　A　total　of　163,740　s　of　data　was　collected.　The　close　contact　ratios　in　HST,　TT,　WWR,　and　CWR　was　5.8%,　64.0%,　7.7%,　and　49.0%,　respectively.　The　average　interpersonal　distance　between　passengers　was　0.85　m,　0.92　m,　1.25　m,　and　0.88　m,　respectively.　The　probability　of　face-to-face　contact　was　9.5%,　70.0%,　64.2%,　and　5.8%　across　each　environment,　respectively.　When　all　passengers　wore　N95　respirators　and　surgical　masks,　the　personal　virus　exposure　via　close　contact　can　be　reduced　by　94.1%　and　51.9%,　respectively.　The　virus　exposure　in　TT　is　about　dozens　of　times　of　it　in　HST.　In　China,　if　all　current　railway　traffic　was　replaced　by　HST,　the　total　virus　exposure　of　passengers　can　be　reduced　by　roughly　50%.　©　2023　Elsevier　Ltd