Two weeks after setting a nationwide deadline for removal of lead pipes, the Biden administration is imposing strict new limits on dust from lead-based paint in older homes and childcare facilities.

A final rule announced on Thursday by the Environmental Protection Agency sets limits on lead dust on floors and window sills in pre-1978 residences and childcare facilities to levels so low they cannot be detected.

Paint that contains lead was banned in 1978, but more than 30m American homes are believed to still contain it, including nearly 4m homes where children under the age of six live. Lead paint can chip off when it deteriorates or is disturbed, especially during home remodeling or renovation.

“There is no safe level of lead,” said Michal Freedhoff, EPA’s assistant administrator for chemical safety and pollution prevention. The new rule will bring the United States “closer to eradicating lead-based paint hazards from homes and childcare facilities once and for all”, she said.