Gov. George Deukmejian has announced the appointment of four new members to state boards. Paul W. Cane, 64, of Greenbrae, was chosen for the board of the California Exposition and State Fair, also known as Cal-Expo. Frank R. Ciofalo, 49, of Lafayette, was appointed deputy chief for occupational health in the Department of Industrial Relations' Division of Occupational Safety and Health. Thomas M. Cromwell, 62, of Lancaster, and John H. Luas, 58, of Saratoga, were appointed to the state Mining and Geology Board.