Active vs. Passive Radon Mitigation – Choosing the Right System

You’ve tested your home and found hazardous radon levels. Now it’s time to reduce that lung cancer risk by installing a radon mitigation system. But should you go with an active or passive set-up? Understanding the pros and cons of active and passive radon mitigation helps homeowners choose the best system design for their house.

The Dangers of Radon Gas Exposure

Radon is an invisible, radioactive gas that arises naturally from underground uranium decay. It seeps into homes through cracks and gaps in the foundation where it accumulates and further decays into radioactive particles. Inhaling these particles exposes your lungs to radiation that causes genetic cell damage and eventually cancer.

Radon is the second leading cause of lung cancer in the U.S. after smoking. About 21,000 lung cancer deaths occur annually due to radon as estimated by the EPA. Radon mitigation systems are the only effective way to reduce health risks by lowering home radon levels.

How Radon Mitigation Works

Radon mitigation prevents radon gas from entering the home and safely vents any radon from below the foundation before it can accumulate indoors. This is achieved through a network of plastic pipes installed through the foundation floor slab or crawlspace.

A fan connected to the pipes creates suction that draws radon from underneath the home. The gas gets vented up and away from the house through the pipes. Sealing foundation cracks is also key to stop radon entry in the first place. Proper mitigation can reduce indoor radon levels by up to 99%.

Comparing Active and Passive Mitigation

There are two main types of radon mitigation systems for homes – active and passive. The EPA recommends active sub-slab depressurization (ASD) as the most effective method, but passive can work in some cases. Here’s how they differ:

Active Mitigation

  • Uses electric-powered fan to create radon exhaust suction
  • Provides highest radon reduction, usually up to 99%
  • Requires small amount of ongoing electricity
  • Has higher equipment and installation costs
  • Needs occasional fan testing and maintenance
  • Works in most high radon level situations

Passive Mitigation

  • Relies on natural thermal convection, no fan
  • Provides variable radon reduction around 50-70%
  • No energy costs, quiet operation
  • Lower equipment and installation costs
  • Rarely needs maintenance
  • Works best in certain limited applications

Choosing Between Active and Passive

In most cases, experts recommend installing an active mitigation system when your home has high radon levels. Active mitigation works better at reducing radon to acceptable levels in these situations:

  • Initial radon level is very high – 10 pCi/L or greater
  • Tightly sealed, energy efficient home construction
  • Cool climates with lower natural ventilation
  • Living space is directly above high radon source like a crawlspace
  • Previous passive mitigation attempt failed

Passive mitigation may be adequate when:

  • Initial radon level is slightly elevated between 4 – 10 pCi/L
  • Testing shows passive reduces radon below 2 pCi/L
  • Warm climate has more natural ventilation
  • Open-concept home construction and layout

Work with a qualified radon mitigation contractor to evaluate your home’s specific conditions and determine if an active or passive set-up is the best solution. Combining both passive and active techniques is also an option. Getting radon levels down is what matters most.

Ensuring Healthy Indoor Air Through Mitigation

Don’t let radon gas accumulate in your family’s home another day. Contact radon professionals to explore mitigation options and install a system tailored to your house layout and radon risks. With the right mitigation approach, you can take control of this invisible health hazard and breathe easy knowing your home’s air is safe from radioactive radon.

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