Original rule filed July 3, 1991; effective August 17, 1991. Emergency rule filed September 2, 2009; effective through March 1, 2010. Emergency rule filed September 2, 2009 expired; rule reverted to its previous status on March 2, 2010. Amendment filed April 23, 2010; effective September 28, 2010. Repeal filed March 23, 2021; effective 6/21/2021.