143. For the purposes of this Division,(a) “person directly assigned to work under x-rays” means a person who works in a controlled zone;
(b) “staff” means every person working in a general medical imaging or specific diagnostic radiology laboratory;
(c) “person not directly assigned to work under x-rays” means a person who, exposed in the course of professional activities to x-rays, does not usually work in a controlled zone;
(d) “physicist” means a person holding an undergraduate degree in physics or the equivalent and competent in radiation protection;
(e) “controlled zone” means those zones of the laboratory within which workers are liable to receive dose equivalents superior to the maximum permissible dose equivalents established in Schedule 8 for persons not directly assigned to work under x-rays.