12 hours prior to testing and throughout the testing duration closed house condition must be maintained (as explained below). Please make sure tenant/owner is aware and has all the windows closed the night before the inspection.

Some Information on Radon, how we test and instructions in preparation for your Radon Testing Service.

Radon is an odorless, tasteless, and colorless gas formed by the natural radioactive breakdown of uranium in soil, rock, and water. The radon outdoors is diluted by fresh air, but radon can penetrate any type of building, become trapped and can increase to high levels.

As most home inspectors do we use charcoal canisters testers to test for radon. Each charcoal canister contains activated charcoal. Radon is adsorbed onto the charcoal and then measured at our lab by counting with a sodium iodide detector.

Once the canister is set testing is between 2 to 6 days. Within the testing time frame we will pick up the canister and hand carry it to the lab. By hand carrying it to the lab we ensure a quicker turnaround time than most. Once it is in the lab the canister is analyzed and a lab report is generated. Once we receive the lab report we send it out immediately. Unfortunately we have no control over the lab but their turnaround is usually only a day or two depending on their work load. Rest assured we will send out the radon report as soon as we receive it.

Closed House Condition

Short-term tests are usually 2 to 6 days long and are done under “closed-house” conditions.  Closed house conditions mean that the house is closed up for at least 12 hours before the test and for the duration of the test. 

• Exterior windows and doors are kept shut, except for normal entrance and exit.
• Fans and blowers which move air from the outside of the house to the inside, or exhaust inside air to the outside, are turned off, including swamp coolers.
• Whole house fans should be off.
• Air conditioners should be put on “recycle” or “max.-cool,” but not on the “fresh air” setting.
• Combustion or makeup air to gas fired appliances are NOT to be closed.

 The house can be occupied during testing, provided the “closed house” conditions described above are maintained.

If testing during warm weather, keep the air-conditioning on and set the fan to recycle indoor air.  Do not use the “fresh air” setting.  Evaporative coolers, sometimes called “swamp coolers” should be turned off during the test to avoid bringing outdoor air into the house.

Leaving doors and windows open during the test is improper and can invalidate a test. It should also be noted that moving the testing device during testing will also invalidate the test.

More information can be found at www.njradon.org