As schools around the U.S. increasingly switch to green cleaning programs in efforts to protect student and staff health, legislators in at least four more states have passed green clean schools legislation. The movement’s momentum during times of economic hardship for school districts and cleaning companies underscores the practical, cost-effective nature of green cleaning.

“What we’re seeing is a real movement as more school leaders recognize green cleaning as a simple change that goes miles in protecting the health of everyone in the school building,” said Mark Bishop, deputy director of the Healthy Schools Campaign, an independent not-for-profit organization dedicated to healthy school environments. “It’s a common-sense, cost-effective switch for schools, and it’s simply the right thing to do.”