It's called Polar Pipe. I've never used it.

I skimmed though this and concluded if, from the beginning, the USA had been using ground level discharge like our hockey loving friends up North, there would be no compelling evidence to switch the standards to above roof discharges for radon.

Page 35 paragraph 3 says what I've always suspected and Canadian already know: "In summary, this study of 10 houses near Harrisburg, PA found that ground level discharge of ASD mitigation system exhaust did not increase indoor radon concentrations when compared with traditional roof top exhaust."

The other interesting tid bit I took away was very low level of air a radon fan pulls out of the building envelop as measured by ACH50 blower door tests. The worst house at 14.3 CFM with most being way lower. Not a big number! A Clothes dryer can pull more 10X that amount of air. Again statements like radon fans contribute significantly to air/energy loss, or 50% of the operating cost of radon fan is the homes energy loss, are not even close to be proven by this study.

We need more work like this, real building science based and industry experience.

Marcel, I live in Minnesota and share the same climate zones and 90% of the Canadian population. Look at page 7 of Ryan Fox's post https://files.dep.state.pa.us/RadiationProtection/RadonDivision/RDPortalFiles/2021/Re-entrainment_Final_Report_Aug-12-2021.pdf . The most egregious example was a radon fan pulling 14.1 CFM with most being much lower. Small data set sure, but if like the half dozen blower door tests I've been involved with depressurization from radon fans is very small at worst and non existent at best. If a radon fan causes backdrafting imagine what a 100 CFM bath fan will do.

Your assumption that 50% of the air being pulled from a radon fan in conditioned air from inside the building may be wildly overstated. I've been party to several blower door tests, where every exhaust appliance is turned on and off and measured for volume of air loss. Range hoods, bath fans, ERV etc. In all cases, no measurable air loss was detected from radon fans. One house had a Festa Fury moving more more 200 CFM and still no measurable air loss. That house had a ACH50 score of around 2, so pretty tight building. In all cases, all measurable air from the fans came from outside the building envelope. If the heating and cooling impacts of a radon fan were significant, we'd know about it here in Minnesota by now. The operating cost between a 15W vs 50W fan is really negligible if in fact it little impact on HVAC costs. A larger fan may in some cases reduce the need for basement dehumidification reducing net energy usage and improving overall air quality.

Agree that one should do PFE but making it a requirement is an overreach.

Robert. Having mitigated over 2000 homes myself, I've had numerous examples of homes where we could not achieve anything close full PFE containment but achieved excellent post mitigation test results and houses with excellent PFE coverage and still needed additional work. Four thousand homes without a single failure. Really?? Here in Minnesota, the majority of suburban homes we work on have drain tile, a code requirement since the 80s. Drilling a bunch of test holes in homes like these with highly finished basements is often impractical and unnecessary. Add in-floor radiant heat to the equation and every additional hole is like Russian roulette, even with an infrared camera.

I'm not aware of the history of how the Radon Mitigation Standards for Existing Homes became "Soil Gas Standards" but I can't help but believing this organizational scope creep is causing more problems than it's trying to solve. Radon and Vapor Instrusion systems on the surface may look like the same thing but they are very different animals that need to be kept in their own cages. For starters, VI mitigation addresses human made pollution, culpable entities , environmental agencies, litigation and liability of an offender. Radon on the other hand is a decay product of elements created in neutron stars billions of years outside of any statute of limitations. VI systems need to be designed, engineered and documented to a preponderance of evidence that demonstrates theoretic effectiveness. Radon Systems can be proven effective with a simple inexpensive radon tests. Conflating the two standards of practice needs to be recognized as a mistake by AARST and be undone.

MN Plumbing Code 305.4 specifies a 4 ft. interval as do most local pluming codes that follow the national standard.

FYI Randy, the plumbing code did change a couple of years ago to require 4 foot supports on horizontal piping to appease the powerful J-Hook lobby. The standards should just say "meets or exceeds" local plumbing codes instead of alway having to adjust to code changes.

Collin - I'm kind of amazed that you can use a 15 watt fan on the majority of your installations. Our typically garage attic fans require such long pipe runs, 30 to 40 ft (10 to 12 meters) plus multiple elbows to get to the required discharge point that the pipe resistance would consume most the available suction from such a small fan. Do you typically use an interior fan with a sidewall discharge?

These changes are bordering on insane with little science behind them. The biggest problem stems from including soil gas standards with radon mitigation. They are not the same and need to be separated. Unlike most soil gas (VOCs etc.), radon can be easily and cheaply tested following a mitigation project. PFE testing is good practice and a predictor is a system "may" work. Radon tests are the proof that is does. Combining these standards is a mistake. I've had enough of the soil gas community highjacking AARST. Go play in your own VOC sandbox.

Bob - The issue isn't about adapting a business model to alarms as a value add service. Also,AARST standard does not require pipe insulation but our MN building code does require R-8 insulation for vent pipes in attics above conditioned space. The fact is, suppliers have not made available proven and affordable alarm solutions that comply to the AARST standard. For a given niche, expensive hardwired alarms are a good fit. In fact, we are adding one to installation in a multi-million dollar home this week. It requires us bringing in my licensed electrician and pulling extra permits, costs an average homeowner who doesn't fly private can afford. (Yes the homeowner does own a Gulfstream)

Tony, I wasn't trying to denigrate the hard work of the committee, or comment with it's superior or inferior to other standards groups. I have great deal of respect for the work being done. My point is that unlike any other licensed states, that I'm aware of, Minnesota, directly incorporates by law the AASRT/ANSI standards which in fact make it the "law" of the land here. The current MDH rules compel them to use and enforce the standard without exception. Unlike MDH, DOLA, our building officials, have discretion to which ICC codes to incorporate, enforce or change regardless of their process and who get's to vote on them. Bottom line, if the ANSI/AARST standard says we have to wear purple socks, purple socks it is. Same goes for alarms.

Bob Wood, Are you suggesting that in addition installing non-existent, reliable and cost effective alarms, mitigation companies alter their business models to include paid service agreements to service those alarms? Also, when your van had warranty work done by the dealership, Mercedes paid them for that work. When was the last time your fan supplier paid you to replace a fan under warranty?

Given that this post is the 122nd one in this conversation, the topic of alarms is far from being resolved.

Minnesota Administrative Rules 4620.7500 states Radon measurement professionals and radon mitigation professionals measuring radon in single-family residences must:
. . . . .
E. Radon mitigation professionals performing radon mitigation in houses must comply with Soil Gas Mitigation Standards for Existing Homes (ANSI/AARST SGM-SF-2017) or successor ANSI/AARST standards.
. . . . .
Violations subject to civil money fines of up to $10,000

Unlike 15 years ago, the standards committee is actually writing enforceable laws, at least for us in Minnesota. Who's the fox and who's the hen-house?

The way I read it that the active alert monitors requirement is tabled for now. Correct me if I'm wrong? More importantly, I have grave concerns that a member of the standards committee also has regulatory authority over radon professionals in their state. It's an obvious conflict of interest. We don't allow law enforcement to make the laws.

Randy, I not sure what the soil conditions are like at this house but I've had couple of difficult houses that had great PFE and still high radon. All had really pourous rocky soil and the answer was "flow" Swapping 3" pipe to 4" was the answer.

It seems there is a lot of unfounded emphasis on cold weather performance on radon systems being discussed here. Freeze ups are rare and resolve themselves within a day or two. Systems installed in Climate Zones 6 and 7 do have unique challenges and most reputable mitigation professions know what they are and do their best to minimize them and education their customers. We for example almost never install critter guards because they quickly build up ice. Building codes are climate zone specific, perhaps our standards should be too.

When SGM-SF 2017 was implemented, the standards committee a incorrectly anticipated suppliers would be able to develop “improved and cost-effective products” by 2019. None to have done so to date. There have been no new commercially available monitor products released subsequent to it’s publication. The only solutions that meet all the requirements of the standard are monitors the operating on 120v AC household power. All of those solutions cost over $120.00 and need to be wired to a separate circuit from the fan (9.2.3.2). With customary mark-up and the cost of an electrical contractor need to install a circuit for a monitor, the customer cost would easily exceed $500.