Each first responder shall satisfactorily complete initial training in first aid, including cardiopulmonary resuscitation, as soon as practical, but in no event more than one year after the date on which he or she became first responder; except that lifeguards shall satisfactorily complete initial training in first aid, including cardiopulmonary resuscitation, within 15 days after the lifeguard's first day of employment.
105 CMR, § 171.100