Cal. Health & Safety Code § 115150

Whenever the department finds that an emergency exists requiring immediate action to protect the public health and safety, the department may, without notice or hearing, issue a regulation or order reciting the existence of the emergency and requiring that action be taken as is deemed necessary to meet the emergency. Notwithstanding any provision of this chapter, the regulation or order shall be effective immediately. Any person to whom the regulation or order is directed shall comply therewith immediately, but on application to the department shall be afforded a hearing within 15 days. On the basis of the hearing, the emergency regulation or order shall be continued, modified, or revoked within 30 days after the hearing.