Section 23E. Nothing in this section shall be construed as preventing or restricting the practice, services, or activities of:

(a) any person licensed in this commonwealth by any other statute from engaging in the profession or occupation for which he is licensed, or

(b) any person employed as an athletic trainer or occupational therapist or occupational therapy assistant or physical therapist or physical therapist assistant by the Government of the United States or any agency of it, if such person provides occupational therapy or physical therapy solely under the direction or control of the organization by which he is employed, or

(c) any person pursuing a supervised course of study leading to a degree or certificate in athletic training or occupational therapy or physical therapy at an accredited or approved educational program, if the person is designated by a title which clearly indicates his status as a student or trainee, or

(d) any person fulfilling the supervised field work experience requirements of this section, if the experience constitutes a part of the experience necessary to meet the requirement of that section, or

(e) any person performing athletic training services or occupational therapy services or physical therapy services in the commonwealth if these services are performed for no more than two days in a calendar year in association with an athletic trainer or occupational therapist or physical therapist licensed under this section, if the person is licensed under the law of another state which has licensure requirements at least as stringent as the requirements of this section.