Mich. Admin. Code R. 325.51105
Rule 5. To achieve compliance with the provisions of R 325.51103 and R 325.51104, administrative or engineering controls must first be determined and implemented if feasible. If such controls are not feasible to achieve full compliance, then personal protective equipment or any other protective measures must be used to keep the employees exposure to air contaminants within the exposure limits prescribed in these rules. Any equipment and technical measures used for this purpose must be approved for each particular use by a competent industrial hygienist or other technically qualified person. If a respirator is used, its use must comply with the provisions of Occupational Health Standard Part 451. "Respiratory Protection."
Mich. Admin. Code R. 325.51105