Hema, I don’t think any jurisdiction would require the inspectors to fix anything.

In my experience, it’s good to choose the testing companies/individuals who focus only on testing or inspecting alone and do not provide services that those tests or inspections recommend. Home owners face enough unknowns as it is, and reducing any possible conflicts of interest is a good thing.

Hema: I also did the long-term test with the alpha track sensor. I had it in the basement, so it was higher than my readings from upstairs, 10.3 pCi/L vs. 7.7 pCi/L on my 7 day test.

I think the green, yellow, and red zones in the Airthings radon readings are in the right places. Mostly I just look at the numbers averaged over various time periods, though.

If a homeowner is testing for themselves, they’re not mandated to fix it, at least not in most places. But if it’s part of a required test for a real estate sale, maybe so.

What do you think of the Airthings threshold values in the green, yellow and red zones?

Also, after an inspector has tested a basement of an older home, are they mandated to fix it, or is it up to the homeowner?

A digital manometer that can read differential pressure in the sub-one inch (0.01”) water column range will do the trick – an old fashioned slope-gauge manometer (no batteries needed) is my favourite measuring tool for this (reasons are too numerous to list here). Check out Dwyer – a company that specializes in low pressure measurement. Regardless of the measuring instrument, you will need some basic training in what, where and how to measure. ERV manufacturer’s literature may have enough info on testing and balancing for you to get a good feel on how to get the required information.

Thanks, that is what I had heard. I tested the water in my new house and the radon is very high. My neighborhood is it’s own water district, and said Idaho doesn’t require them to test for that so they don’t. So I’m doing an education campaign with my neighbors so they understand this issue. This has gotten many of us thinking our neighborhood should test for more things than the state mandated minimums. Mine also tested high in nickel.

What would be your strategy for pressurizing a crawl and house, when you have an active radon system in such a tight house in a cold climate? Building scientists have said neutral is ideal, or slightly positive. My architect thinks that with an active system the crawl will want to be negative and you should keep it negative to avoid radon & mold from going from the crawl into the house. My answer to that is I built my house to be as mold-free as humanly possible because I am massively sensitive, and my crawl is like a clean room. Because if in fact we get mold down there it’s just as bad for me as if it’s in the house. So I think the whole house should be neutral or slightly positive. (I control ventilation in the crawl as well as the house through a Zehnder, and we have points where there is direct open connection between the crawl and the house. Basically open drains in case of leaks.)

Regarding water, yes I agree that’s what I heard about ingested water. But water from a showerhead aresolizes the radon and the info I read said that is often worse than the actual radon coming from the ground.

Alison, I have an ERV up and running now and would like to monitor the air pressure to ensure it stays neutral. What kind of device do you buy to measure air pressure in a home?

Thanks!

To comment, we had a radon barrier, and extensive piping system throughout the crawl which should have been venting passively, and were at neutral pressure. And the radon was still 40 last winter until we turned on the radon fan. (We’d hoped it would be lower and we could just handle it with the ERV air exchange, but with it that high we didn’t even try that.)

Also just because you live in a high radon area doesn’t mean you have it under your house. It really varies a lot from house to house.

Robin: I prefer any method that works.