If Denver teachers strike next week, classes will be canceled for about 5,000 preschoolers who attend district schools.

Superintendent Susana Cordova announced the decision Wednesday afternoon during a press conference. It will affect 3- and 4-year-olds in 220 classrooms scattered throughout the city.

Lisa Roy, the district’s executive director of early education, said a variety of logistics make the prospect of hiring hundreds of qualified substitute preschool teachers impossible on a short timeline. Staff working with preschoolers are subject to rules governing child care, which are stricter in some ways than rules for K-12 teachers.

“I feel for the families,” Roy said. “I hope they’re able to come up with viable, safe options for the littles during this time.”

Emergency child care can be tough to find for any family, but may be especially hard for low-income working families. About 70 percent of the district’s preschool students qualify for free or reduced-price school meals, a proxy for poverty.

One of the biggest stumbling blocks in finding substitute preschool teachers is that they must be fingerprinted and undergo background checks through two state departments — the Colorado Department of Education and the Colorado Department of Human Services. For 220 teachers, the process wouldn’t be done by Monday, Roy said.

Background checks through the Colorado Department of Human Services take seven to 10 business days if there are no arrests on record or extenuating circumstances, department officials said. Roy said she submitted her own fingerprints and background check materials to the department a couple weeks ago, but since she’s still waiting for the results, she would not be allowed to be alone with preschool children during a strike.

Officials from the Department of Human Services said they talked with Denver district leaders about waiving two state preschool rules during a strike — the class size cap of 20 students and the teacher-student ratio requirement of 1-to-10. The waivers would only be granted for classrooms with a qualified staff member, such as a paraprofessional, and another district staff member who has the background checks and training required by state and federal law.

Roy said paraprofessionals working in the district preschool classrooms do have the credentials needed to serve as lead teachers, but their union contract — separate from what district teachers work under — doesn’t allow them to take that role.

Roy said Wednesday evening that the district would send home information about cancellations during a strike to preschool families soon.

Correction: A previous version of this story said background checks through the Colorado Department of Human Services take four to eight weeks on average. That is only the case when an individual has charges on their record. Most background checks take seven to 10 business days.