US DOT Hazardous Materials Regulations (49 CFR Parts 171 to 180) 172.700-704: Hazmat employee training: general awareness, function-specific, safety, security awareness and in-depth security training, initial within 90 days and recurrent every three years, with records (172.700 to 172.704)

A hazmat employer must train and test each hazmat employee in general awareness and familiarisation, function-specific requirements for the employee's duties, safety (emergency response information, hazards and protective measures), security awareness, and in-depth security training where the employer must have a security plan. New employees or employees changing function must be trained within 90 days (performing the function under direct supervision meanwhile) and all must receive recurrent training at least once every three years; in-depth security training is given within 90 days of a security plan's implementation and at each revision. The employer must create and retain for each employee a record of the training date, description or copy of materials, the trainer's name and address and a certification of training and testing, kept while employed and 90 days after, and available to DOT on request. Drivers also need the 177.816 training and rail, air and vessel employees the mode-specific additions.