The U.S. government on Monday released updated guidelines for how federal contractors may adhere to rules on vaccinating their workforces and keeping employees safe from COVID-19.

According to the amended rules, contractors will not be required to have every employee vaccinated by the Dec. 8 deadline set by the Biden administration in its Sept. 9 executive order that initiated the vaccine mandate for large employers. Instead, contractors can demonstrate they are “working in good faith and encounter challenges with compliance with COVID-19 workplace safety protocols” at the time of the deadline without risk of being penalized.

The new updates also provide some flexibility in how contractors deal with their unvaccinated workers.

“A covered contractor should determine the appropriate means of enforcement with respect to its employee at a covered contractor workplace who refuses to be vaccinated and has not been provided, or does not have a pending request for, an accommodation," read the new guidance.

The penalties for non-compliance can include those already permitted under contractors’ collective bargaining agreements. Some measures that the rules also suggest include moves to usher unvaccinated workers toward compliance such as a limited period of counseling and education, but allow for more onerous steps like prohibition from entering a federal workplace and being placed on administrative leave as an "adverse action" is considered.

Employees with pending vaccine exemption applications would still be required to follow COVID-19 safety guidelines as they await the results.

Biden’s executive order applies to private employers with 100 or more employees that must require either vaccinations or weekly testing to come into compliance. The Labor Department’s Occupational Safety and Health Agency (OSHA) is responsible for drafting guidance for employers, but its rule is still currently being reviewed by the Office of Management and Budget (OMB) before it is implemented.

Several contractors have already taken the lead in implementing their own policies to come into compliance with the administration’s directive, including Microsoft and IBM. In the former's case, they announced their vaccination mandate for employees a whole month before Biden announced his executive order.

Others in the private sector have welcomed the mandate, but several business groups recently urged Biden to push back the Dec. 8 deadline until after the holiday season. They fear that the current deadline may leave them short-staffed at a time when labor shortages are already rife across the economy.