This is a great idea. This New Jersey township requires that landlords test for radon levels every five years. There has been a lot of debate in our society of governmental regulation versus free markets. Most of the time, free market works quite well; they are especially good at distributing scarce resources to the highest and best use. However, when you can neither see nor smell nor detect without special equipment the signals that the market is sending you, a little governmental intervention works quite well. That is especially true when the risks cannot come back to haunt you for years and years.