OSHA released its long awaited emergency temporary standard (ETS) on Nov. 4, calling for employers with 100 or more employees implement vaccine mandates by Jan. 4, 2022, or ensure that unvaccinated employees are undergoing weekly COVID-19 testing. Those workers who have not yet been fully vaccinated will need to start wearing face masks in the workplace starting Dec. 5, according to the new regulation. 

A three-judge panel on the Fifth Circuit court on Friday did rule to permanently block the vaccine rule, but many employers are still working to comply since many experts predict the Supreme Court will need to ultimately decide the fate of the mandate—and that will likely take place after some of OSHA’s deadlines have passed. 

OSHA’s rule, which is set to be in effect for about six months, notes that for counting purposes, the rule’s effective date was Nov. 5, 2021. Employers who had 100 or more employees on that date are included, as well as those that hire enough workers to boost them over that threshold while the ETS is in effect. But if an employer loses enough employees to dip below 100, it’s still covered. Once a company qualifies, it’s included until the ETS expires. 

OSHA also explained that companies in a franchise relationship need to only count workers who work out of the corporate or principal office. Franchise locations that are independently owned and operated are considered separate entities. Employees supplied by staffing agencies can be excluded from counts as well, since they would be counted by the agency. 

Yet there are some major exemptions to the rule that employers should consider as they start to work toward complying with the ETS. 

Independent contractors

Although OSHA’s mandate covers a broad swath of employees—temporary workers, seasonal workers, and minors—the agency’s rules do not generally apply to those who are self-employed, including independent contractors.

“OSHA has no jurisdiction, just like EEOC, and doesn’t cover independent contractors,” says Robert Duston, a partner in Saul Ewing Arnstein & Lehr’s labor and employment practice. King & Spalding partner Amanda Sonneborn agrees, saying she works with a lot of companies in the gig economy and maintains the OSHA ETS doesn’t apply to independent contractors.

Not only are independent contractors not covered by the mandates, they also do not count toward the 100-employee threshold, according to the Department of Labor. 

There were about 10.6 million independent contractors, or about 6.9% of total employment, in the U.S. as of 2017, according to the Bureau of Labor Statistics’ latest report, released in 2018. 

Fully remote employees

In its new mandate, OSHA included an exemption for workers who work remotely. That could potentially eliminate a lot of workers, depending on how their work schedule is set up. Nearly half of full-time U.S. employees, about 45%, were still fully or partially working from home as of September, according to Gallup’s polling. 

But OSHA does note that if employees are occasionally required to perform in-person work, they must be fully vaccinated or obtain a negative test result within seven days of heading into the office.

The challenge for employers may be determining who fits the criteria of a fully remote employee. “If you’d asked us two years ago who was a remote worker, it was really clear—there are people who came into work and there are people who didn’t,” Sonneborn says. 

Now employers will likely need to calculate how frequently remote workers are interacting with other employees in-person, she says, adding that the OSHA requirements are likely going to force companies to have conversations with people and set expectations around returning to work that many employers have been letting ride. 

It’s also worth noting that the remote worker exemption doesn’t apply to employees who travel, Duston says. That includes traveling salespeople, delivery workers, those who go into people’s houses, and those don’t have a fixed workplace but may enter an office or warehouse or pick up equipment or tools—such as repairmen or installation experts. “We don’t know exactly how broadly employees and customers are intended, but workplace is kind of a pretty broad definition,” Duston says. 

Isolated workers

If an employee works by themselves, they may also be exempt from the vaccine and testing requirements. OSHA’s ETS does not apply to employees who “do not report to a workplace where other individuals such as coworkers or customers are present,” according to OSHA’s summary of the new regulation.

The trucking industry, in particular, applauded this exemption because by that definition, many truckers may be exempt since they operate their routes solo. Additionally, many drivers are often independent contractors who are owner-operators of their own freelance business. 

But again, there are restrictions on this exemption. A Labor Department spokesperson told Fortune that vaccination and testing requirements for unvaccinated workers would apply to truckers who work in teams—for example, those who have two people in the truck cab—or those who interact with people indoors at the origin of their route or at their destination.

Outdoor workers

Because research has shown that COVID-19 does not spread as easily outdoors, OSHA also included an exemption for those who perform their work exclusively outside. But many experts say that the carve-out is very narrow and should be applied only to employees who spend no time indoors. 

“There are a lot of workplaces you may think of as outdoor—the construction industry is one of them—that are never 100% outdoors,” Duston says. Many times even those who work outside all day have brief indoor team meetings. In those cases, employees would still need to meet the ETS requirements of either being fully vaccinated or undergoing weekly testing.  

Employers can, however, adjust their routines and procedures to accommodate this, says law firm Fisher & Phillips. For instance, construction crews could move meetings outdoors and set up equipment pickups and drop-offs. 

Although OSHA has provided a few exemptions to the new testing and vaccine mandates, Duston says it’s worth noting that employers have the discretion to expand requirements. Keep in mind that before the vaccines were available, many companies had masking policies in place that applied to employees, customers, visitors, and vendors. “It was the business imposing it on those who were entering into their premises,” Duston says. 

Some employers may want to further limit the risk of an outbreak and create a level playing field for anyone entering the premises. “I think a lot of employers, once they get the handle on this set of rules and put them in place, will proceed to expand that potentially to others.”