It’s been nearly a year since the state of Maine began requiring all residential rentals to be tested for radon, but it’s not known how many landlords complied and how many are skirting the law.

The state office in charge of the radon testing program saw a surge of test results and questions about the law just before and after the March 1, 2014, deadline. The high volume of incoming test results continued through June and picked up again at the beginning of winter, said Bob Stilwell, head of the state radon program.

So far, his office has recorded more than 30,000 new test results for radon, a colorless, odorless gas that is the second-leading cause of lung cancer after smoking.

But it’s not known how many properties or units that number represents because some buildings need only one test, while some larger buildings need up to 30, Stilwell said. What’s also unknown is how many buildings should have been tested.

“That’s the question everybody asks,” Stilwell said.

The problem is there is no comprehensive database of rental properties in the state, he said. The 2010 U.S. Census found that there were about 160,000 renter-occupied units in the state, but it doesn’t separate that into short-term or seasonal rentals, which aren’t required to be tested.

“What part of the pie it is, I don’t know,” Stilwell said of the tests received so far. “I think it’s a big chunk because we get very, very few calls from tenants saying, ‘My landlord hasn’t tested.'”

An older database manager program the office previously used no longer works, so the workers have been uploading the results to spreadsheets, Stilwell said. He said he hopes to have another database for the results within 18 months.

The office needs the data in a more usable format to be able to effectively search the records and compare the properties tested to lists of rental properties from other state departments or agencies, such as the Maine State Housing Authority’s database of landlords receiving rental assistance funds, he said.

First law passed in 2009

Before the rental radon testing law, the office had hundreds of thousands of test results dating back to the 1970s, Stilwell said. He had estimated that around 10 percent of rental properties were already tested, but he wasn’t sure.

State lawmakers first passed the law in 2009 requiring tests for radon in the air and water, if from private wells, in all residential rental buildings. In 2011, lawmakers pushed the deadline for compliance from 2012 to March 1 of last year.

Homeowners aren’t required to test their houses, but it’s common before real estate transactions.

Radon is produced by the breakdown of uranium in soil, rocks and water and can rise into homes through cracks and holes in their foundations. Historical radon testing data from the state shows that about one-third of all private homes in Maine have high levels of radon.

In 2013, state lawmakers amended the testing law further, including taking away the requirement for landlords to mitigate high levels of radon.

Ventilation pipe for mitigation

Mitigation is often done by installing a ventilation pipe to move air from beneath the basement slab to outside the house and typically costs more than $1,000 for a single-family home.

Landlords aren’t required to fix high levels of radon, but a landlord or tenant can terminate a lease with a minimum of 30 days of notice if the landlord doesn’t mitigate it.

“There are a lot of landlords that are mitigating the building and fixing it because they care about their tenants, and that’s a wonderful thing,” Stilwell said.

“Some landlords are saying, ‘Hey, I really can’t afford that right now.'”

But others are just telling their tenants they can leave if they don’t want to live with the high radon levels, he said.

Although the law doesn’t require mitigation, it does require landlords to notify tenants of the test results regardless of whether the amount is below the allowed level and before new tenants sign a lease or within 30 days of receiving the results for current residents.

If tenants never hear about test results from their landlords, they can contact the state’s radon control program to see if tests were submitted to the state.

Complaints to attorney general

“I think most people that are going to do the testing have pretty much done it,” Stilwell said.

Stilwell said he’s only received about two dozen calls from people saying their landlords hadn’t tested for radon, and he referred them to the attorney general’s office.

Tim Feeley, the spokesman for the office, said in an email that the office has received a half-dozen complaints about radon testing over the last year, one of which was successfully mediated.

Feeley said he doesn’t know what happened with the other five complaints.

Landlords or property management companies not meeting the requirements of the law can be fined up to $250 per violation, but Stilwell said it’s not clear who has authority to enforce the penalties.

He said it’s his understanding that the attorney general’s office will fine the landlords, but Feeley said his office isn’t the primary enforcement authority for the law.

By not doing a test or not notifying tenants, a landlord also breaches the implied warranty of fitness for human habitation, meaning a tenant could file a civil lawsuit against a landlord or property owner.

Pine Tree Legal Assistance, a free legal service for people with low incomes, advises in an online guide that a judge in a warranty of habitability suit can order that a landlord fix the apartment, lower the rent until repairs are made or pay back some of the rent that has been paid.

Testing of buildings of fewer than 10 units that don’t have an elevator shaft, forced hot-air heat or a central air-conditioning system can be done by the landlords using kits that cost as little as $30. But for all other buildings, testing must be done by a testing company certified by the state.