A new set of home demolition rules intended to control the spread of asbestos and lead dust took effect this month in Portland.
The Portland City Council approved the new regulations in February, but administrative rules weren't in place until July 1, The Oregonian/OregonLive reported .
The new rules require contractors to take down parts of homes by hand if using heavy equipment could release lead or asbestos, and it also requires water misting to further stop the spread of dust.
The new regulations are among the strictest around lead dust in the nation. The rules are intended to keep airborne particles from leaving the work site.
"This is just common sense," said Perry Cabot, who manages Multnomah County's lead safety program. "These rules do increase the cost and time that these projects take, but they're not whimsical and arbitrary."
There have already been 144 homes demolished this year, while contractors had applied for or received permits for more than 100 more as of July 1.
Exposure to asbestos fibers in the air can cause cancer and other lung ailments, while lead dust can lead to brain damage.