Home > Uncategorized > Airthings Wave Plus vs RadonEye RD200

Airthings Wave Plus vs RadonEye RD200

November 16, 2020 Leave a comment Go to comments

We have a couple of Airthings Wave Plus devices to keep track home air quality metrics like CO2, TVOC (Total Volatile Organic Compounds), and radon levels. While the non-radon readings like CO2 and temperature have been accurate and responsive, over time it was noticed that the radon readings did not reflect environmental changes like the opening of windows to cycle air. Instead the radon readings seemed to raise and lower at their own volition, as if the readings were being pulled from some other house or based solely on the weather. I chalked it up to rain just having an outsized effect on radon levels but given I still wanted to track down potential radon sources (like was our open basement floor shower drain a source?) I knew the Wave Plus devices weren’t likely to be much help.

Given that a RadonEye RD200 was purchased to compare against the Wave Plus. It touts itself as being “>10x more sensitive and accurate than other home radon detectors“. The Airthings Wave Plus apparently takes 4 Radon readings an hour. The RadonEye device itself takes readings every 6 minutes (10 readings an hour) though the data export from their app only yields data in 1-hour increments, with each data point being a 60 minute moving average. Neither the Wave Plus or the RadonEye are certified, but the RadonEye Pro is “AARST-NRPP and NRSB” certified and both the Pro and non-pro version tout very similar features, including the sampling rate and touted accuracy, so there’s a non-trivial chance that the non-pro version is as good as the Pro version just without the certification backing it up. In fact, in an email exchange with Radon Corp it was confirmed that the non-pro RD200 device is factory calibrated just like the Pro version though the difference being you can’t re-calibrate the RD200 after purchase. (also it’s expected to remain accurate “for 7 years”).

The primary sensor location for testing is a basement office (11’x13′) with a single small 1’x4′ window that opens in half for a 1’x2′ opening. There’s a small but strong 9″ fan (Honeywell HT-800) inside the window bay that pulls in enough fresh air to easily turn over the room’s air several times over the course of the day with fresh air. The entire bottom floor is a daylight basement set into a steep hill where the backside of the house is fully below ground and the front side of the house is fully above ground. We live in a Zone3 radon region (where average indoor levels are noted as <=2 pCi/L) but more locally the risk is actually moderate. Both of the sensors are on a small shelf near each other about 4′ from the floor and 1′ away from the wall.

With only a couple of day’s worth of results to compare against the Wave Plus so far the RD200 seems to be much more responsive and seems to track well against changes in the environment. For the last 48 hours here is an Excel rendering of the data exported from RadonEye’s app and the same timeframe via Airthing’s https://dashboard.airthings.com:

The RadonEye RD200 clearly follows whether there’s fresh air being introduced.

And a summary table for that same 48 hour period comparing the low, high, and average pCi/L readings for the two devices:

Low pCi/LHigh pCi/LAverage pCi/L
Airthings Wave Plus0.32.21.1
RadonEye RD20000.171.450.7

So if you squint the numbers are in roughly the same ballpark, it’s not like the Wave Plus measured pCi/L > 4 and RD200 measured <0.5. But still, the Airthings measurements are about 41-55% higher at any given time and seems to be moving with a 12-hour moving average or… something. For instance at 5pm today 11/16 the RadonEye noted levels of 0.17pCi/L, after a full work-day’s worth of a fan pulling in fresh air. However Airthings recorded it at the highest level for the 48hour period at 2.2pCi/L!

To be updated after a full week’s worth of data… See here for the update.

Categories: Uncategorized


Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: