Thanks for all the great input! The solution turned out to be “back to the basics” seal seal and check the seal job again. The slabs have a 1 sq. foot open area under each tub drain that is open to the gravel base. Each under tub area needed to be accessed and the area sealed well. 8x8 inch openings and access doors are cut and installed. We use cans of spray foam with 36 inch straws attached to get to the slab openings. The foam tends to bridge and leave openings which needed to be re-sealed following initial cure. There are 12 to 16 openings per space…so an equivalent large opening when unsealed. Again thanks for the input!

There will be approx. 100+ systems when completed and the client is thinking they may want a remote monitoring system that sends an email or text alert when the static pressure is out of spec…
Any ideas?

Thx….DT

Bill, your paper was excellent and I would hope everyone takes a look at it. Looking at the AARST “May 2014 Position Paper on ASD Discharge” this issue obviously has been around a long time and I’ve not yet seen the science behind the “position”. Many years ago when I was an Sr. Environmental Engineer at VA DEQ and TN TDEC in their air programs, the old saying was “The solution to pollution is dilution” which at one time led to taller and taller smoke stacks. Of course we now know that’s not the only answer, and with the ability to accurately test and model the stack exhaust/plume we can design better more efficient systems. The AARST position is similar to “if a tall stack is good...taller must be better”. I think we are better than that, AARST (Dallas) what’s it going to take to put together a complete study on this? Bill presented a self funded study which supported a hypothesis which honestly most of us have had since we installed our first systems.

Bob, 5 hours one way...that’s dedication! We have been doing radon and vapor mitigation for the past 15 years, and yes we have seen many mitigation companies come and go (and fixed alot of the junk they installed). Like you, we could never make it on the $800-1500 rates that SOSRadon and other sites so easily quote. But, what I am questioning is why these sites have not been updated? It is misleading for people to think their radon issue is going to be fixed for 800 bucks in most cases. If they think the fix is $800 and their first quote is $2500...of course now they are going to get 4 more quotes, waste everyones time bidding a simple radon system and possibly won’t even put the system in because they budgeted the $800. My point is, in order to support the mitigation business model, we need to ensure the public has reasonable expectations of cost and quality.

The more I look into this, the more disturbing it becomes.
As the need to keep adding "crap" to the system to meet new regs. After looking at Bill Brodhead's paper on ground level exhaust and Canada's allowing ground level exhaust...why are we not walking this back and calling for ground level exhaust and a Radoneye monitor. No need for an alarm, manometer, heat tape, exhaust stack, extra pipe, pipe hangers, and increased w/c rates due to ladder work above 6 feet. Are we looking at the science and or are we looking at who can benefit from selling parts to mitigators??

I have no problem with increasing regulatory requirements to make safer systems and better mitigators, but those who feel the need to increase the regs should also be required to educate the public on the realistic cost of the systems which they are requiring. For example: Looking at SOSradon...the old $800 TO $1500 numbers which have been used for years are still out there. If you are paying your taxes, business license, workmans comp, liability insurance on business and vehicles, decent pay for workers, licensed electrical work etc.....who can put in even a simple system for $800 - $1500 and make a reasonable profit ....maybe a discussion for a different day.

State licensure requirements are a welcomed thing as long as the rules are not applied in an Arbitrary and Capricious mannor. I would be happy to pay for such as long as the state provides funding and resources to apply and enforce. Otherwise, we end up with quality companies being tasked with policing the bottoms feeders that are still going to put in poor quality systems.

Thank you for the guide. It is our opinion that it would be impossible to 100% ensure we could protect our crew and our clients from possible cross contamination of the virus. Given that our services are not emergency based, we have posponed all of our scheduled work 30 days. All but a couple clients have understood. Additionally we have sent most of our N-95 masks and some tyveks to a local hospital in need. If you have extra PPE supplies, many ER and ICU doctors and nurses need them to remain safe...I would encourage you to donate if you are able.
Stay safe...DT