In , OSHA requires that 51³Ô¹ÏºÚÁÏ evaluate workplaces to determine if confined spaces are "permit-required." If a Permit-Required Confined Space (PRCS) is identified, 51³Ô¹ÏºÚÁÏ is responsible for informing exposed employees as to their existence, location, and the hazards each space poses. Traditionally, this is accomplished by posting danger signs at the space entrance as well as implementing a permit system.