Frontier’s policy will take effect June 1.

Frontier Airlines will implement temperature screenings for all passengers and employees prior to boarding aircraft, making it the first major U.S. airline to announce plans to do so.

Starting June 1, the carrier said it will use touchless thermometers and those with a temperature 100.4 degrees or higher will be denied boarding in an attempt to limit the spread of COVID-19. Frontier said if a passenger’s temperature exceeds that number, and flight departure time allows, customers will be “given time to rest” and receive a second temperature check.

If a passenger doesn’t pass the second check, they will be denied boarding and can have their travel rebooked for a later date. Employees will be held to the same standard, Frontier said.

“The health and safety of everyone flying Frontier is paramount and temperature screenings add an additional layer of protection for everyone onboard,” Frontier Airlines CEO Barry Biffle said in a press release.

Frontier announced in late April it will require all passengers to wear face coverings — with that policy going into effect May 8. All major U.S. airlines have announced they will begin to require passengers to wear masks starting this month.

The decision comes one day after the company received backlash from lawmakers and later rescinded its plan to to charge passengers extra to guarantee the middle seat next to them would be empty.