California Code, Business and Professions Code - BPC § 20700

(a) “Industrial hygiene” means the science and art devoted to the anticipation, recognition, evaluation, and control of environmental factors or stresses which may cause sickness, impaired health and well-being, or significant discomfort and inefficiency among workers or among the citizens of a community.

(b) “Certified industrial hygienist (CIH)” means a person who has met the education, experience, and examination requirements of an industrial hygiene certification organization.

(c) “Industrial hygiene certification organization” means a professional organization of certified industrial hygienists that has been established to improve the practice and educational standards of the profession of industrial hygiene through a certification process, by certifying industrial hygienists through an examination administered by the certification organization.  The organization shall have the certifying examinations evaluated by a national testing service and shall maintain certification criteria that are at least the equivalent of the American Board of Industrial Hygiene.