Nothing in this chapter shall be construed to prohibit any otherwise unlawful practice which is necessary to protect the health or safety of the general public. Any person who asserts that an otherwise unlawful practice is necessary shall have the burden to establish that:
A. The practice is necessary to protect the health or safety of the general public; and
B. There exists no less discriminatory means of protecting the health or safety of the general public. The burden may be met by demonstrating that the practice is consistent with the department of health and human services guidelines entitled "Recommendations for preventing transmission of infection with human T-Lymphotropic virus type III/Lymphadenopathy-associated virus in the workplace" announced in November, 1985, or specifically authorized by the laws and regulations of the state of California or the United States. (Prior code § 74.01.150)