HOUSTON — The Biden administration is not requiring FBI fingerprint background checks of caregivers at its rapidly expanding network of emergency sites to hold thousands of immigrant teenagers, alarming child welfare experts who say the waiver compromises safety.

In the rush to get children out of overcrowded and often unsuitable Border Patrol sites, President Joe Biden’s team is turning to a measure used by previous administrations: tent camps, convention centers and other huge facilities operated by private contractors and funded by U.S. Health and Human Services. In March alone, the Biden administration announced it will open eight new emergency sites across the Southwest adding 15,000 new beds, more than doubling the size of its existing system.