Section R. 325.52004 - Control methods for enclosures and controlled processesRule 4.
(1) An employer shall ensure that an enclosure is provided at a stationary source unless the omission of the enclosure does not impair control.(2) A controlled process shall be designed and regulated to prevent the creation of a hazard to health or life. If the director determines that there may be an immediate danger to health or life due to the failure of the process design or regulatory device, then he or she may require that the process fail-safe in such manner to avert the hazard.Mich. Admin. Code R. 325.52004