How To Activate a Passive Radon Mitigation System

In this video, we'll look at activating a passive radon mitigation system in Rachael Malberg's home.

Rachael was diagnosed with lung cancer and has never smoked. Radon is believed to be what caused her lung cancer.

Rachael is an advocate for radon testing and mitigation. I am forever grateful for her work and the lives she has saved by sharing her story.

Thank you for trusting us with your family's health and home, Rachael.

What is a Passive Radon System?

A passive radon mitigation system is basically the guts of a radon system installed during your home's construction.

It includes a gas-permeable layer and a 6-mil vapor barrier below the concrete floor.

The gas-permeable layer is typically 4-inches if washed river rock or soil gas mat.

If rock is used below the slab, then at least 10 feet of perforated pipe is embedded in the rock layer.

There is also a 3-inch vent PVC pipe that connects to the soil gas mat or perforated pipe. This can also connect to an interior drain tile system.

The 3-inch vent pipe then goes from the sub-slab connection, through the concrete floor, up to the attic through the interior walls of your house, and out through the roof.

The vent pipe is insulated in the attic to prevent freeze-up and condensation issues. It is also pitched to drain water to the sub-slab material.

A passive system works by relying on the stack effect. It will be more effective if the vent pipe stays warm and is as straight as possible with a limited number of fittings.

An outlet is required in the attic next to the radon vent pipe. This allows for the addition of a radon fan in the future.

Openings to the soil need to be sealed during the construction of your home.

These openings include the sump basket cover, floor to wall joints, control joints, block tops, plumbing block-outs, plumbing penetrations, and crawl spaces open to the soil.

Studies have shown that passive radon remediation systems reduce radon levels by approximately 50 percent.

Passive radon mitigation systems became a requirement of Minnesota homes built after June 1, 2009.
Activating a Passive System

Activating a passive radon mitigation system means adding a radon fan in the attic to create suction on the gas-permeable layer or soil gas mat below your home.

A visual gauge, called a U-tube manometer, is attached to the radon vent pipe. The U-tube measures your radon fan's suction and indicates whether or not your radon fan is working.

An active radon system monitor is also attached to the vent pipe. An active system monitor will have an indicator light and an audible beep if it senses a drop in airflow or pressure inside the vent pipe.

Sealing openings to the soil is a crucial aspect of radon mitigation. Sealing is the key to designing and engineering effective and efficient radon reduction systems.

Fan selection is determined by doing pressure field extension testing. Pressure field extension testing measures the strength and extent of suction that the radon system creates under your home's concrete floor.

The key to getting your radon levels as low as possible is the engineer a mitigation system that creates suction under your entire home.

Problems with Passive Radon Mitigation Systems

Passive radon mitigation systems components are not typically installed by radon mitigation contractors. They are installed by excavators, concrete crews, and plumbers.

This can lead to issues when we are hired to activate a passive radon system.

We often find inadequate sealing, water traps created in the vent pipe that block airflow, no room in the attic to install the radon fan, no pitch on the vent pipe to drain condensation, an improper connection to the sub-slab material, and a few other problems I'm forgetting to mention.
Final Thoughts

The home in this video is the worst passive system I have come across so far.

We had budgeted a day to activate the system and two days to shoot interviews with Racheal and get some footage for Fantech.

It ended up taking three and a half days to complete activating Racheal's system.

The film crew did not stay as late as I did every night, so I apologize that we didn't capture some details.

Timecodes:
00:00 Intro
00:33 What is a passive radon mitigation system?
01:13 Adding the radon fan to a passive radon system.
02:58 Drilling test holes to measure pressure field extension.
03:27 How to install a sealed cover on a sump basket.
04:54 Sealing floor to wall and control joints with Radon Sealant.
06:13 Measuring pressure field extension
07:14 Troubleshooting why we have weak pressure field extension.
08:10 Enlarging radon suction point
09:32 Installing U-tube manometer and radon system alarm.
10:55 Installing a larger radon fan.
11:42 Setting the potentiometer of the Fantech Rn 4EC radon fan.
13:00 Radon system explanation
15:59 Radon test after mitigation

Feel free to reach out to us at https://www.americanradonmitigation.com/free-estimates/ or 612-474-1004.

-Jesse Green

Видео How To Activate a Passive Radon Mitigation System канала American Radon Mitigation