California Code, Business and Professions Code - BPC § 2630.4

(a) A “physical therapy aide” is an unlicensed person, at least 18 years of age, who aids a licensed physical therapist consistent with subdivision (b).

(b) The aide shall at all times be under the supervision of the physical therapist. An aide shall not independently perform physical therapy or any physical therapy procedure. The board shall adopt regulations that set forth the standards and requirements for the supervision of an aide by a physical therapist.

(c) Physical therapy aides shall not be independently supervised by a physical therapist license applicant, as defined in Section 2639, or a physical therapist student, as defined in Section 2633.7.

(d) This section does not prohibit the administration by a physical therapy aide of massage, external baths, or normal exercise not a part of a physical therapy treatment.