This bill directs the Secretary of Transportation to establish new regulations concerning the transportation of hazardous materials. Specifically, it mandates that all refrigerated shipping containers must display placards to alert emergency responders to the potential for pressurization, irrespective of the specific cargo they are transporting. The regulations aim to enhance safety by providing critical information to first responders. Furthermore, the bill requires the Secretary to conduct a comprehensive study to evaluate whether refrigerants should be formally recognized as a distinct hazard category, examining its interaction with existing classifications and its broader regulatory implications.