Preparing For a Radon Measurement

When preparing for a radon measurement it is very important to maintain closed building conditions for a period of twelve (12) hours prior and during the test. Whether the house is open or closed for short or extended periods of time prior to the 12 hour requirement has little or no impact on the measurement. Closed building conditions are considered as follows.

  • Normal entry and exit of the home is permitted as long as the door is closed behind the person and not allowed to remain open for extended periods of time.
  • Sliding glass doors should be used only when absolutely necessary.
  • All windows should remain closed during the measurement.
  • Heating and cooling systems should be operated in the normal fashion with the fan set to “auto” and the temperature maintained between 68 and 74 degrees.
  • Ceiling fans should not be operated in the room where the testing monitor is placed.
  • Whole house attic fans should not be operated during the test.
  • Portable humidifiers and dehumidifiers should not be operated during the testing.
  • Fireplaces should not be operated during the test and the chimney damper should be closed.
  • Operation of clothes dryer are permitted as needed.
  • Newly constructed homes should be in “ready to move in condition” when the test is performed.

The requirements listed above are designed to protect both the seller and the buyer as some of the requirements can lower the radon concentration and others can raise it.

Most of the more expensive continuous radon monitors, such as the Accustar RS800, have sensors built in to detect changes in room temperature, relative humidity, barometric pressure, movement and tampering.

Hopefully the information provided here will help you understand what the requirements are for a radon measurement.
​If you should have any questions or concerns please feel free to contact us at (618) 641-9106.