Quality Assurance & Quality Control
Introduction to Radon Mitigation
Worker Health & Safety
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When to Test

  1. Request by Concerned Homeowner [Non-Real Estate Transaction]
  2. Real Estate Transaction [Time Sensitive]
  3. Retest – A Short-term or Long-term measurement which replaces a previously invalidated measurement. A Retest is also recommended every 5 years or when significant have been made to the home such as:
    • Structural or HVAC changes, such as additions to the home
    • Significant alteration to ventilation, changes to mechanical systems, or weatherization of building
    • Previously untested or unoccupied areas in ground contact become occupied.
    • Installed mitigation system is altered or repaired
    • Occurrence of earthquakes, construction blasting, or formation of sink holes nearby
  4. Diagnostic – Samplings of radon decay products obtained by a mitigation contractor to determine where or how to best mitigate a problem or by a researcher for study purposes.
  5. Post-mitigation – Short term measurements conducted by a measurement professional in order to determine the effectiveness of mitigation systems.
  6. New Construction – Newly constructed homes should be tested only after all work is complete and closed-building conditions can be maintained.