Although Radon gas test in homes, is usually optional (not mandated by State) however if you have a basement and intend habitation therein, we recommend a radon gas test before closing, because if it is excessive, the seller would pay for the mitigation and you would have a piece of mind knowing that your family is safe.
Radon is a naturally occurring radioactive gas in the soil and is produced by the normal decay of uranium to radium to radon. Radon levels can vary from property to property, only few feet apart. Radon is an issue in all types of homes, regardless of age, type or architecture, every where.
Radon is colorless, has no smell, and is an inert gas that poses no danger directly, however because radon continues to decay to polonium, lead and progeny, which are radioactive. These radioactive progeny lodge in the lungs, bronchi, and trachea. The radiation disrupts and mutates lung cells which results in lung cancer. Radon is estimated to be the second leading cause of lung cancer in the United States. Its health risk increases with the length of exposure and concentration level of the radon. It is estimated that more than 20,000 people die each year as a direct result of Radon exposure.
Pressure differential in air pressure between the basement and the soil beneath accelerates the migration. Radon can move through small cervices in the soil and rock below the home, seeps through dirt floors, floor drains, sump pits, cracks in the foundation and basement floor and up through hollow core block foundation walls.
The NJ DEP and EPA standards of mitigation and level of concern are set at 4 picoCuries of radon per liter of air (4 pCi/L). This is a concentration of 70,000 atoms of radon in each liter of air (about 2 million radon atoms in every cubic foot of air). Although it is a low concentration, say about one radon atom per billion-billion air atoms but because the radon atoms are so radioactive it can be detrimental. Humans take about 20 litters of breath per minute. At 4 pCi/L it means about 10,000 radioactive atoms in the lungs, trachea, and bronchi per minute.
Testing is recommended by short term (2-6 days) tests with charcoal cans (accumulors), or long term (3-12 months) by alpha track or electret. We recommend a short term charcoal test for real estate transaction. The cost of testing is about $ 100.00 to $ 150.00.
There are several remedies for radon reduction. Most common is the "sub-slab depressurization" system by sub slab collection and removal by piped fan. It eliminates maximum radon gas from below the concrete slab foundation. Remediation costs about $ 1,250 to $2500 depending upon home configuration. For more information, please see EPA Radon.