DETROIT — As COVID-19 vaccinations increased and mask guidelines were loosened earlier this summer, Joyce Webster Jones took down the “masks required” sign at her business, Source Bookseller in Detroit’s Midtown.

However, she changed her mind when infection rates began to rise again because of the delta variant.

“Then things started getting dicey for me, so we put signs up on the door again,” she said. “And the orders came behind that masks should be encouraged.”

With the delta variant fueling fears of a fourth COVID-19 surge in Michigan, weary operators of shops, restaurants and other retail businesses face a quandary: Do they reinstitute mask mandates — in line with advice from national, state and local health officials — and risk backlash from customers tired of restrictions as the pandemic reaches a year and a half?

Smaller stores, like Source Bookseller, might be more likely to require or request that patrons wear masks, while larger stores and chains might be more lenient, experts say. One business, Michigan First Credit Union, has taken a stance in the opposite direction, instead frowning on mask usage — unless the masks are clear.

Big chain retailers like Walmart and Home Depot are taking a middle approach: They’re requiring masks for employees and unvaccinated customers, and encouraging mask usage for shoppers who have gotten the shots.

Jennifer Rook, vice president of communications and marketing for the Michigan Retailers Association, said businesses are concerned about backlash from customers.

“In the spirit of the safety of the employees, a number of retailers have said, ‘You know if customers are walking in without masks on, let them,’ “ she said. “It’s not worth getting into a confrontation about. Employees are still wearing masks.

“I have started to see retailers say ‘will you please put a mask on, it’s in the safety of everyone in our store, it’s a smaller setting for our employees.’ I’m starting to see masks being put out again, but it’s not consistent. It’s really a case-by-case basis.”

The Centers for Disease Control and Prevention guidance suggests that residents statewide should mask up when indoors in public because of COVID-19 transmission rates in Michigan. Cases are up significantly since early August, when fewer than half of Michigan counties had substantial or high rates of spread.

Statewide positivity has increased to 8.6 percent, continuing a two-month upward trend.

Some stores are considering the level of transmission in their area when adopting mask policies, said Julie Swann, a department head and professor of the Fitts Department of Industrial and Systems Engineering at North Carolina State University. She has done work forecasting and modeling interventions related to the COVID-19 pandemic.

Swann said a pharmacy might be more likely to ask patrons to wear masks due to serving a vulnerable clientele than a hardware store that has a mix of customers. Store owners may also take into account the size of their store, she said.

“Places that have smaller spaces, ceilings that are not as tall, it’s an all-indoor setting as opposed to being partially outdoors, it’s a crowded setting,” she said. “All of those things make the environment higher-risk than a big store where you have more space to spread out.”

Jones sells a large inventory of nonfiction books in a small, light-filled shop along Cass Avenue amid Wayne State University’s campus. She said her customers have been compliant with the store’s mask policy.

“If they come in without a mask, I point to our sanitization station,” she said. “They always put them on. If they don’t, they leave. That’s OK with me.”

Customer Darius Casey, 50, of Detroit came into the bookstore recently with his sister, Kessa Jones, 45, who was visiting from Chicago. The two happily complied with the mask requirement.

“I’m glad,” Casey said. “I actually look for that when I go to a store. I’m an educator. I don’t want to take anything to one of my students.”

At least one business has frowned upon masks in recent weeks. A sign outside of Michigan First Credit Union in Eastpointe last week stated: “No masks preferred. Clear masks permitted.”

In early August, the credit union had asked its customers at its standalone branches not to wear masks, posting a sign stating, “We want to see your smiling face. Please no face coverings.” Branches inside Walmart and Kroger stores follow the guidelines of those businesses, according to the credit union, which has 27 branches in Metro Detroit and the Lansing area, according to its website.

Credit union officials say they are changing their policy this week to ban masks that aren’t transparent.

“Our primary concern with members wearing masks is the overall security risk that face coverings pose,” Michigan First Credit Union President and CEO Michael Poulos said in an emailed response to questions. “It’s important that our team members and security cameras have a complete, continuous and unobstructed view of each individual conducting financial business with us to prevent physical and financial threats. While the state of Michigan’s COVID-19 executive orders were in effect, we temporarily adjusted our long-standing safety and security practices to allow for masks to be worn.”

Poulos said the credit union will provide clear masks for customers for a limited time. Those who are not comfortable with the policy can bank at branches inside Walmart or Kroger stores or use the credit union’s other services, including the drive-thru, ATMs and mobile app.

One recent day, most customers seen entering and exiting the credit union in Eastpointe were wearing masks, including Don Moore of St. Clair Shores. He said he wears his face covering most places he visits and doesn’t like that the credit union plans to limit mask usage to clear ones.

“I don’t think it’s a good idea because we’re still in a pandemic,” he said. “It’s not over with and things are still bad.”

Despite having varying stances on customer mask usage, many businesses are still requiring their employees to wear them. Among them is Home Depot.

“We require all associates, contractors and vendors to wear a mask while indoors at all U.S. Home Depot stores, distribution centers, office locations and customers’ homes or businesses,” company spokeswoman Margaret Smith said. “We also ask customers to wear masks while in our stores and continue to offer masks to those who don’t have one.”

Walmart has taken a similar stance, requiring its employees to wear masks inside stores, clubs, fulfillment centers and distribution centers.

Rook said most of the 5,000 member businesses of the Michigan Retailers Association require masks of their employees.

“People are very concerned about the variant, employers want to keep their employees safe,” she said. “That’s the best way they know right now: Following CDC guidance. We’ll see over the few weeks to come.”