The first rule, which goes into effect on January 4th, requires companies with 100 or more employees to ensure that their workers are fully vaccinated against Covid-19 or that they test negative for COVID-19 at least once a week. The second requires health care workers to be vaccinated by the same deadline with no option for testing. 

Importantly, the vaccine mandate does not apply to employees who “do not report to a workplace where other co-workers or customers are present, or who work exclusively from home,” notes labor and employment lawyer Keith Wilkes, a partner and shareholder at law firm Hall Estill. 

That means that OSHA will not require fully remote employees at companies like Facebook, Twitter, Dropbox, Ford, and Slack, which have allowed some employees to work from home, to report proof of vaccination or take weekly COVID tests—so long as they stay away from the office. 

If an unvaccinated employee has been teleworking for two weeks or more but must report to their office, where other employees will be present, they will need show proof of a negative COVID test within the seven days prior to visiting. 

Employers have 60 days until they must comply with the rules, but a long list of legal and reporting preparations await them. 

Employers will have to establish a compliant written policy on vaccination, determine the vaccination status of each employee, obtain acceptable proof of vaccination, provide support for employees who still need vaccination, create and enforce mask policies for those who are unvaccinated, and make certain records available to the Occupational Safety and Health Administration, who is enforcing the rule for most office workers (the healthcare rule will be enforced by the Centers for Medicare & Medicaid Services). 

They will also be required to provide their employees with information about their policies, information about vaccination efficacy, safety and benefits, and about criminal penalties for knowingly providing false information, said Wilkes.

The government is relying on companies to do the majority of rule-enforcement. There are only a few thousand OSHA workers around the country, and they will mainly be responding to complaints of non-compliance. Employers who are found guilty of breaking the rules will pay up to $13,653 per serious violation and 10 times that for repeated violations. 

Twenty-one states have opted out of OSHA’s governance and instead have OSHA-approved enforcement agencies for workplace safety. Those states will have to enact vaccine-requirement rules that are at least as effective as the federal rule within the next 30 days.

More health care and Big Pharma coverage from Fortune:

• ‘Vax’ is Oxford English Dictionary’s word of the year
• With a vaccine mandate looming, these apps help businesses check which employees got vaxxed
• Novavax COVID-19 vaccine’s long-delayed global rollout will start in Indonesia, fueling hope for more equitable distribution
• 100 million Indians have skipped their second vaccine dose, leaving the country vulnerable to a third COVID wave
• A COVID scare trapped 33,000 visitors inside Shanghai Disneyland in a ‘surreal’ scene