Mont. Code Ann. § 50-79-403

When 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 rule or order reciting the existence of the emergency and requiring that such action be taken as considered necessary to meet the emergency. Notwithstanding any provision of this chapter to the contrary, the rule or order is effective immediately. A person to whom the rule or order is directed shall comply with it immediately but on application to the board shall be afforded a prompt hearing. On the basis of the hearing the emergency rule or order shall be continued, modified, or revoked by the board within 30 days after the hearing or when the emergency no longer exists.