Cdc back in January was in contingency mode. They announced critcal staff mode. Where you may work with mild to moderate symptoms. No negative test is required.
It is up to your jurisdiction to have adopted and approved the critical recommendations. This for hcp where staffing levels are critical and may dirextly negatively impact patient care.
Some jurisdictions that have adopted this recommendations may also require hc facility to actually declare your entity has moved from contingency to critical.
I would google cdc critical staffing etc.. also check with your jurisdiction. Also check if they need to declare it. If they do and your boss has not declared he might have to do some foot work or red tape stuff as well as having policies and procedures to implement declaration of critical mode adoption.
Make him do extra paperwork if he thinks he can just go into critical mode. Hopefully he has not filed the paperwork so you can become a thorn in his side.