Her Executive Order No. 2020-91 states: 

With this order, I am creating an enforceable set of workplace standards that apply to all businesses across the state. These standards will have the force and effect of agency rules and will be vigorously enforced by the agencies that oversee compliance with other health-and-safety rules. Any failure to abide by the rules will also constitute a failure to provide a workplace that is free from recognized hazards within the meaning of the Michigan Occupational Safety and Health Act, MCL 408.1011. To enforce compliance, the governor also signed Executive Directive 2020-6 which appoints a Director of COVID-19 Workplace Safety within the Department of Labor and Economic Opportunity (LEO).

Here’s the time frame the Governor has laid out to comply with her workplace requirements:

(a)  Develop a COVID-19 preparedness and response plan, consistent with recommendations in Guidance on Preparing Workplaces for COVID-19, developed by the Occupational Health and Safety Administration and available here. By June 1, 2020, or within two weeks of resuming in-person activities, whichever is later, a business’s or operation’s plan must be made readily available to employees, labor unions, and customers, whether via website, internal network, or by hard copy.

The attorneys Jonathan Kok and DeAndre’ Harris of  Warner Norcross + Judd wrote up the following summery of the Governor’s workplace guidelines.

Summary

• Develop a COVID‑19 Preparedness and Response Plan consistent with the Occupational Safety and Health Administration’s Guidance on Preparing Workplaces for COVID‑19 (“Plan”) and make it available to employees, customers and the public by June 1, 2020, or within two weeks of resuming in-person activities, whichever is later. When employees are on-site, a supervisor must be present to implement and monitor the control strategies developed under the Plan.  
• Provide COVID‑19 training to employees that covers, at a minimum: (1) workplace infection-control practices; (2) proper use of personal protective equipment; (3) steps an employee must take to notify the business of any symptoms or suspected/confirmed diagnosis of COVID‑19; and (4) how to report unsafe working conditions. 
• Conduct a daily entry that includes self-screening for employees and contractors to identify any symptoms and suspected or confirmed exposure to COVID‑19. 
• Provide non-medical grade face coverings for all employees and require that they be worn when employees cannot consistently maintain six feet of separation. 
• Increase facility cleaning and disinfection. 
• Within 24 hours of becoming aware of an employee who tests positive for COVID‑19, notify the local health department and all employees/contractors who may have come in contact with any employee who tests positive for COVID‑19. 
• Restrict business travel to essential travel only. 
• In addition, the Order lays out individualized and detailed obligations for employers in the following industries: construction, manufacturing, laboratory, retail, office and restaurants/bars.
• Failure to abide by the Order can result in a civil penalty issued by the Michigan Occupational Safety and Health Administration (MiOSHA). The amount of the civil penalty issued by MiOSHA varies depending upon the seriousness and the willfulness of the violation. 

To view Executive Order 2020-92, click the link below: