Washington ( CNN ) -- Authorities evacuated Union Station , the main train terminal in Washington , D.C. , for part of Sunday afternoon due to a chemical odor from an overheated battery system , according to a spokesman for the D.C. Fire and Emergency Medical Services Department . The evacuation ended just over an hour after it began , after a hazardous materials team responded and all train service had been suspended , said fire department spokesman Peter Piringer . One person was taken to a hospital for evaluation after complaining of dizziness , Piringer said . The odor , described as smelling like sulfur or natural gas , was due to the battery that backs up the train platform 's lighting system getting overheated , the spokesman said . Amtrak spokesman Marc Magliari said all rail traffic in and out of the station was suspended for 75 minutes due to the evacuation . Delays from the temporary suspension would probably affect train service through the afternoon , Magliari said . Subway service continued to operate during the evacuation , but trains were not stopping at Union Station , according to the Washington Metro Area Transit Authority . Regular subway service was to resume shortly after the evacuation lifted .
Chemical odor causes hour-long evacuation at Washington , D.C. 's Union Station . Cause of odor was overheated battery system , official says . One person taken to hospital for evaluation after complaining of dizziness . Amtrak train service was suspended for 75 minutes , spokesman says .