OSHA requires employers to provide a safe and healthy workplace. That includes being prepared for workplace emergencies. In most cases, employers must enact an Emergency Action Plan that details what employees are to do in the event of a site emergency. The Plan typically includes one or more emergency evacuation maps posted in the facility; training; instruction on safe egress during an emergency; conducting mock drills; and assessing Plan effectiveness. See 29 CFR 1910.38 for more information. https://www.osha.gov/SLTC/emergencypreparedness/gettingstarted.html#business.