According to people familiar with the matter, the factory in Shanghai has been restarting and the company has put in place stringent measures for staff operating in the closed-loop system.

The electric-vehicle maker will provide each worker with a sleeping bag and mattress according to a memo sent to employees. People will be required to sleep on the floor in a designated area, and there will be other spaces for showering, entertainment, and food, according to the memo.

There were 40,000 lost electric vehicles due to the lockdown.

All employees will have to take a nucleic acid test daily for the first three days, have their temperature checked twice a day, and wash their hands four times a day, according to a memo. One of the people said that the allowance would depend on a person's position and level.

A representative from the company didn't respond to requests for comment.

The city of Shanghai has encouraged companies to use closed-loop systems in which workers live at their factories to restart production that was halted due to the city's strict curfew. More than 600 firms have resumed operations, including one that makes laptops for Apple.

The first covid deaths were reported in the city.

On Friday, some employees were told to prepare to enter a closed-loop system on April 17 after a weeks-long suspension as Shanghai attempted to contain the Covid outbreak. To get around restrictions on residential compounds in the city, the company issued a special certificate for those on call and arranged shuttle buses to bring them back to the plant.

Only staff living in the lowest risk residential compounds and those who have completed a two-shot vaccine regime will be allowed to re-enter, joining the 400 staff already on site, according to the memo.

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The last closed-loop workers entered the factory just after midnight and are expected to work in the system through May 1, according to a memo.

Prior to the halt of the Pandemic-inducted halt on March 28, workers in Shanghai were working three shifts a week. Factory staff would work four days and then have two days off. They are being asked to work 12 hours a day, six days straight with one day off, people familiar with the matter said.

In the first quarter of the year, the company's Shanghai plant churned out 182,174 vehicles. It won't be an instantaneous process to ramp production back up.

A person familiar with the matter said that the new closed-loop schedule ofTesla only has inventory for just over two weeks.

With help from Charlie Zhu and Chunying Zhang.