By now, most home sellers and buyers should be aware that radon, a naturally occurring carcinogenic gas, is prevalent in Colorado. Every buyer’s agent should be advising their client to hire an inspector who, in addition to inspecting the home for hidden defects, can perform a radon test.
Radon, at any level, can cause lung cancer, and the EPA has established an “action level” of 4 picocuries per liter (4 pCi/l) above which mitigation is recommended. According to www.cdc.gov, the EPA estimates that radon gas is responsible for 21,000 lung cancer deaths per year, about one-sixth of the annual lung cancer deaths (cancer.org). However, if the radon level is above 4.0 pCi/l using any testing device other than a CRM (Continuous Radon Monitor), such as charcoal or E-perms, a second test is required immediately after, and those results are averaged with the first set of results to determine if mitigation is recommended.
Radon is an odorless, colorless and tasteless gas which is a decay product from Uranium U235. It further decays into polonium, which is what’s harmful to your health. The final decay product is lead.
Home inspectors are still not licensed or regulated in Colorado (something I have argued for), but as of July 1, 2022, only a licensed radon professional can install an approved radon testing device as part of a home inspection, and must follow explicit and detailed instructions for doing so.
Fortunately, my go-to home inspector, Jim Camp of Metropolitan Home Inspections, obtained his radon license and gave us a PowerPoint presentation on the subject at a recent office meeting. Here’s a link to his presentation.
Prior to licensing, any inspector could install the 48-hour testing equipment in a home and leave behind a flyer requesting “closed house conditions.” The device makes hourly measurements, so any violation of those rules would be obvious from looking at hourly variations in the measurements. Only the CRM has hourly results of the concentration levels along with temperature, barometric pressure and relative humidity reading.
But now there are several specific procedures that must be followed, including getting signed approval from the client to conduct the test, and providing advance notice of the test to the owner or occupant. The latter form states that closed house conditions must be initiated at least 12 hours prior to testing, not just throughout the 48-hour testing period.
Another rule is that if the basement footprint exceeds 2,000 square feet, two radon measuring devices must be installed. There are detailed instructions about where a testing device can and cannot be positioned.
Any air exchange systems, such as whole house fans, moisture mitigation systems for homes with structural wood or concrete floors, window air conditioners and box fans must be turned off. In addition, the garage overhead door must remain closed along with the windows and exterior doors including the passage door to an attached garage. An existing radon mitigation system can remain on during the test.