How to calculate 100-employee threshold under OSHA's vaccination ETS

The Occupational Safety and Health Administration’s (OSHA) new rule for COVID-19 vaccination, testing, and facial coverings applies to “all employers with a total of 100 or more employees” during the period it's in effect. In a preamble to the emergency temporary standard (ETS), the agency noted the 100-employee threshold would result in applying the rule to “two-thirds of the nation’s private-sector workforce.” The preamble provides further guidance on how to count the 100 employees.

Calculating employees

As an initial matter, you must determine whether you employ 100 or more employees as of January 4, 2022, the ETS's effective date. Once the threshold is reached, the rule continues to apply even if the number of persons subsequently employed drops below 100. When calculating the threshold, you must include:

• “All employees across all of [your] U.S. locations, regardless of the employees’ vaccination status or where they perform their work,” that is, you must focus on the number of employees rather than on the type or number of workplaces; and
• Part-time employees.

The preamble further indicates “two or more related entities may be regarded as a single employer for [Occupational Safety and Health] OSH Act purposes if they handle safety matters as one company, in which case the employees of all entities making up the integrated single employer must be counted.”

What does this mean?