Another source: https://apnews.com/article/joe-biden-business-health-coronavirus-pandemic-executive-branch-18fb12993f05be13bf760946a6fb89be

The expansive rules mandate that all employers with more than 100 workers require them to be vaccinated or test for the virus weekly, affecting about 80 million Americans. And the roughly 17 million workers at health facilities that receive federal Medicare or Medicaid also will have to be fully vaccinated.