In 1991 , prompted Causation in large part by the Chase Maryland crash , the United States Congress took even broader action and authorized mandatory random drug-testing for all employees in `` safety-sensitive '' jobs in all industries regulated Limiting by the U.S. Department of Transportation ( DOT ) including trucking , bus carriers and rail systems .

The crash Catastrophe involved Cause_to_be_included a signalled rail crossing located very near a highway intersection which was regulated by traffic signals .

While these rebellions differed Change in that they also struggled Hostile_encounter for republicanism , they were inspired Influence by similar social problems stemming from poorly regulated oligarchies , and sought the same democratic ideals , which were also shared by the United Kingdom 's Chartists .