Professional inspections of your home for lead paint and radon can cost hundreds of dollars. That’s why you’ll find $30 do-it-yourself kits in many home centers and hardware stores. Our tests of 18 lead and radon test kits confirm that some are a good first step in identifying whether there’s a problem, but we also found confusing instructions, challenging procedures, and inaccurate results.

Lead-based paint in homes was outlawed in the United States in 1978; many homes built before then probably have some. Lead paint can gradually deteriorate into flakes, chips, and fine dust that’s easily inhaled or eaten by small children, even when it’s covered by many layers of unleaded paint. Lead poisoning has several effects, which can include brain damage and diminished mental and physical development. We tested seven kits; some were faster and easier to use than others.

Radon, an invisible, radioactive gas, results from the breakdown of uranium and radium in the soil and rock beneath homes. Levels vary from day to day. Any building can have radon, but almost one of every 15 homes has elevated radon levels, according to the Environmental Protection Agency. We tested seven short-term kits, three long-term kits, and a digital meter that can be used for either short- or long-term measurements. While some were fine options, three short-term kits were especially inaccurate, unreliable, or both.