Good presentation, 1 thing, vent your vacuum outside.
You can buy PFE test rigs from Radonmatters

Great information Bill, thank you!

We use lay flat air scrubber duct, comes in rolls and you cut it to length.

I agree that outside venting is a good idea however the reality is most crews sent out to do two jobs a day or one big job are too time crunched and not willing or in many cases not capable of doing any system diagnostics. So the concept of OSD was to make it super simple and very quick to do with no math, no extra vacuum airflow or pressure measurements or even needing an app. Obviously you can raise the radon levels way up by venting into the basement. At the same time if you are trying to measure a tenth of a pascal or thousand of an inch vacuum an open window and a bit of wind will make that difficult to see. The solution is to minimize test run time by having a super simple set up that allows multiple test variations at the same time test hole vacuum is being measured.
In about 2 minutes you could test the performance of an RP140, RP145, RN3 and RN4-4 fan with equivalent 3" or 4" piping used. And the installers only need to refer to a chart that is small enough to tape to the body of the fan. As for radon exposure people always forget that risk is based on Dose. Dose requires two components - an exposure and time being exposed. 2 pci/l in your house is 2X12X365 = 8760 pCi/l/hrs. which most of us would not consider a serious risk. If you raised the basement to 20 pCi/l for one hour or 40 for 30 minutes that is 20 pCi/l/hrs.

Bill as a Radiation Safety Officer and a mitigator I disagree with your premise wholeheartedly. I hesitate to say this out loud or worse write it down to someone who has been my go to reference for radon knowledge for over 10 years. I hope we can disagree on this without you taking offence. Radiation science continues to march forward on knowledge about the risk to humans and the ICRP has recently changed the risk that humans are exposed to from radon upwards by 2 1/2 times from 1993 knowledge.

Radiation protection mantra is "As Low As Reasonably Achievable" (ALARA). while you may be mitigating a home that is at 5.3 pCi/l or 200 Bq/m3 under slab radon is typically 10x to 100x the concentration in the home. These numbers are generated by many 100's of homes we have mitigated in Ontario Canada. Homes between 1x and 10x typically have large opening somewhere between the sub slab and the interior of home i.e. opening under tub or shower.

Dumping that level of radiation into your work space because you are trying to hurry to next job is Russian roulette with radiation. Either we are handsome radiation workers worth a bunch $$$ or a bunch of dumb ugly hicks who don't know better. I am hoping my wife sees me as the former.

In Canada from a radiation protection standard, workers are assumed to be exposed for a working day at highest level they are exposed to, unless they are actively tracking their exposure on a hourly basis.
Radiation protection NORM guidance is currently 200 Bq/m3 for Canadian workers for radon exposure based on ICRP 65 (1993), (currently under review).

current radiation protection limits say: (Canadian rules for sure and I believe USA rules as well)
Below 1 mSv dose ................. ALARA
1-5 mSv dose ................ track exposure, document and save for duration of worker life (25 years)
and lower dose ALARA
5-20 mSv dose................track exposure using approved dosimeter (very expensive in our world)
submit results to Government approved agency and lower dose ALARA

See below chart of exposures and how much they have changed since 1993. I apologize in advance for rounding errors.

workplace exposure 2000 hours
ICRP 65 (1993) ICRP Sydney 2015 ICRP 137 12.7 recommendations
Radon level Dose Dose Dose
Bq/mᵌ pCi/l
3000 81 8.69 mSv 45.39 mSv 40.05 mSv
1000 27 6.21 mSv 15.13 mSv 13.35 mSv
800 22 4.984 mSv 12.10 mSv 10.68 mSv
300 8.1 1.869 mSv 4.539 mSv 4.005 mSv
200 5.4 1.246 mSv 3.026 mSv 2.670 mSv
150 4.0 0.934 mSv 2.269 mSv 2.002 mSv
100 2.7 0.623 mSv 1.513 mSv 1.335 mSv
75 2 0.467 mSv 1.134 mSv 1.001 mSv
60 1.6 0.373 mSv 0.907 mSv 0.801 mSv
50 1.35 0.311 mSv 0.756 mSv 0.667 mSv
40 1.0 0.534 mSv

Whoops chart did not translate to this format . what i was trying to show that if worker was exposed at 75 Bq/m3 or 2.0 pCi/l for 40 hrs week/ 2000 hrs per year they are at 1mSv dose under 2018 ICRP guidance.

Please let me clarify i agree wholeheartedly with communication testing. Dumping radiation into your workplace, is just people who lack knowledge of the risk they are exposing themselves to (that was nicer than just saying "STUPID" wasn't it?). Again I say Russian roulette with radiation. Radiation is not a cumulative risk it is a one instance where 6 things go wrong at same time and you have stage 4 lung cancer and you die.

if you own a company and you have employees make sure you clearly document work procedures to lower radon levels in workplace (introduce outdoor air and vent vacuum exhaust outside away from your outdoor air source) otherwise don't plan on leaving anything for your wife or kids, because your workers wife and kids will have it.

Bob, Thank you for addressing worker safety. I’ve seen photos of mitigation employees enveloped in a cloud of concrete dust as they root-hammer through a concrete foundation (saw the photos on a mitigator’s website). Day in and day out silica exposure, radon exposure, adhesive vapors, etc. it all adds up to risks for workers.

The big radon conferences should ALWAYS include worker safety classes. This should include how to identify risks and protect workers. This starts with a company safety plan. Providing safety plan and documentation templates and apps for companies to use makes the challenge of creation, implementation and administration of worker safety much easier and, therefore, much likelier to happen.

I bet very few radon mitigation companies are OSHA compliant. As a result, I bet few mitigation employees are properly protected from workplace hazards. Just my thoughts.

Donald & Bob
Excellent points that we need to do a much better job teaching and motivating worker safety, especially in the states. The intro mitigation course only spends less than an hour on safety over our 3 days. It needs an update. I will put in a plug that we include a safety course at the next conference. I did a quick search and only found one CE course on PPE by spruce so there is a big void there.