Everything AmazonThe increase in Covid-19 cases caused by the highly transmissible micron variant means that warehouse workers in America will have to once more wear masks to work.

Starting today, workers will be required to wear face coverings inside Amazon operations facilities — even if they’re fully vaccinated or live in an area where masks aren’t mandated — according to a notice sent Tuesday to employees, which was viewed by CNBC.

The notice says that “Your safety and health are our top priorities.” Face coverings will be required again due to rapid spread of Covid-19 omicron in the U.S., as well as guidance from medical professionals and public health officials.

Amazon spokesmen confirmed that masks were required at warehouses.

Amazon has reinstated the mask mandate because workers are currently in “peak season,” which is when warehouses are full and overtime employees are required to pack, ship and pick holiday orders.

Amazon and other major corporations have been forced to constantly review their Covid safety protocols since the outbreak. Amazon in NovemberAfter removing its mandate to fully-vaccinated warehouse workers and lifting the mask requirement, removingAnd reinstatingThe mask requirement has been repeated in warehouses many times over the last year.

As the contagious Omicron variant spreads and coronavirus cases rise, companies’ approaches to this virus are changing. Omicron is now consideredThe dominant strain of Covid in the country accounts for 73% sequenced cases.

Amazon is the 2nd-largest employer of Americans. WalmartIt has not mandated vaccinations for workers. It has instead encouraged employees to have the shots by giving them bonuses and running promotions. “Max Your Vax” sweepstakesThe company gave away vacation packages and cash awards to just a few of its employees.

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