DES MOINES, Iowa (AP) — A Des Moines legislator is backing a bill requiring all Iowa school districts to test for the cancer-causing gas radon and make buildings safe if the gas is found. Democratic Sen. Matt McCoy filed the bill this week, saying it’s needed to protect students. The bill is similar to national legislation filed recently by Iowa Congressman Bruce Braley. The bill would require all public and nonpublic districts to test every room of each school. If high levels of radon are found, districts would need to have ventilation system installed to make buildings safe.

Radon is a colorless, odorless gas that leaks through cracks in building foundations. It’s the second leading cause of lung cancer in the United States. All of Iowa’s 99 counties lie in the government’s highest risk zone.