It all rolls back to the Emergency Paid Sick Leave Act (part of FFCRA).  So you have to be "unable to work":

SEC. 5102. PAID SICK TIME REQUIREMENT.
(a) IN GENERAL.—An employer shall provide to each employee
employed by the employer paid sick time to the extent that the
employee is unable to work (or telework) due to a need for leave
because:
(1) The employee is subject to a Federal, State, or local
quarantine or isolation order related to COVID–19.
(2) The employee has been advised by a health care pro-
vider to self-quarantine due to concerns related to COVID–
19.
(3) The employee is experiencing symptoms of COVID–
19 and seeking a medical diagnosis.