Those rules pertain to restaurants, gyms, child care centers, retail stores, and hotels, among other industries.
At child care facilities, health screenings will be required for kids before they're allowed in. Parents and employees must wear facial coverings at all times. Children must do so when outside the classroom.
And for retailers, the city is limiting capacity to 25% for non-essential stores and 50% for essential stores.
Mayor Lightfoot said Chicago could move to the next phase in early June.
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Scott Weiner feels like he is one of the lucky ones as co-owner of the Fifty/50 Restaurant Group. His business Utopian Tailgate can open under Mayor Lightfoot's Phase Three plan because it has a rooftop deck.
"Every day that we are closed in June, we are bleeding out," Weiner said. "Being able to open up a little bit, it's going to help a bit."
Spacing tables 6 feet apart and only allowing six people to a table, restaurants can open as long as they have outdoor space. Indoor dining is allowed only if the tables are near an outdoor opening.
"You have to be 8 feet from an opening, that is at least 50% of a wall," Weiner said.
Weiner's restaurant Roots Pizza, on the first floor, must remain take out and delivery.
Moving into the new reopening phase, the mayor's office expects about 130,000 - roughly one-third of Chicago's workforce - to return to work. If possible, employees are encouraged to continue working at home and employers are being asked to stagger shifts.
"We don't expect everybody is going to come back down to the Loop. Logistically, that wouldn't work, on how buildings operate, how transit operates," said Kiana DiStasi of Chicago Loop Alliance.
Guidelines for office buildings include reconfiguring workspaces to maintain a distance, or installing barriers. Face coverings are required when 6-feet distancing isn't possible.
The city decided to allow 25% capacity for non-essential retail stores, while the state plan allows 50% capacity.
"Because Chicago is a dense city, we believe 25% capacity is the right place to start," said Chicago Deputy Mayor Samir Mayekar. "The mayor has challenged some to make sure it's like a dimmer switch."
READ: Mayor Lightfoot's full plan for reopening Chicago in early June
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While the Carole Robertson Center for Learning awaits the city's green light, the facility has been hard at work to make sure that they'll be able to reopen safely.
"In this space right here, we will have a portable sink. We will do the wellness where we will do the temperature checks, we do symptoms. Parents officially sign their children in," said Bela Mote, the center's CEO.
The center serves nearly 1,000 children in Chicago's North Lawndale and Little Village communities.
"We'll take everything out of here and have two wellness rooms here for our staff or children, if they start to exhibit symptoms," Mote said. "We're asking parents to pick up children who exhibit symptoms within 90 minutes of the call."
While there is some variation between the specific guidelines outlined by the city and the state for day care centers to follow, there's some crossover regarding what parents can expect.
Parents will have a designated drop-off spot and children will undergo daily wellness checks. Facilities will be required to meet strict capacity limits, with no more than eight infants or 10 children to a room. Children will also be assigned to one group, and not allowed to co-mingle with others. There will be a limit on the number of staff allowed to go into each classroom, and staff will be required to wear masks at all times. All meals will be individually wrapped.
"We've weathered the storm with no cases of COVID, so we feel very confident that we will be able to continue on," said Sarah Stoliker, who represents an association of 800 day care centers in Illinois.
Located in southwest suburban Manhattan, First School is one of the few day care centers that have remained open throughout the crisis, catering to the children of essential workers.
Stoliker said she's confident others will be able to operate in a safe and effective manner.
The city's safety guidelines are available for the following industries:
-Childcare centers and family childcare
-Non-lakefront parks (no contact sports)
-Libraries and other city services
-Office-based jobs, professional services, and real estate services
-Hotels / lodging
-Outdoor attractions (e.g., boating - not including the Playpen, non-Lakefront golf courses)
-Personal services (e.g., hair/nail salons, barbershops, tattoo parlors)
-Restaurants and coffee shops (outdoor dining only)
-Manufacturing, construction, and warehousing
-Hospitals, dentists, community mental health centers, and Federally Qualified Health Centers
-Public transit, regional transit, taxis and rideshare
-Gyms (outdoor and 1:1 personal training only)
The full guidelines are available at chicago.gov/reopening.
Resources are also available for employees.
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Businesses are also encouraged to go through a self-certification process.