Validation of Ecosense Radon Detectors' High Performance through Independent Third-Party Testing
Updated on 6/12/2023
Enhancing Credibility: The Significance of Third-Party Validation Studies
As one of the leading providers of both consumer and professional electronic radon detectors and monitoring solutions, Ecosense has made a strong commitment to having its continuous radon monitors available for independent third-party testing. The results to date are persuasive and have surprised the radon industry.
Detecting radon levels accurately can be challenging due to various factors such as temperature, humidity, and radon fluctuations caused by weather and ventilation. Even when lab-based tests are conducted, extending those results to real-world scenarios can be difficult. Low count rates and signal-to-noise ratio issues further add to the problem, making precision an even greater challenge than accuracy.
RadonEye, an Ecosense radon detector, underwent rigorous radon chamber testing at esteemed institutions such as the University of Michigan, Kansas State University, Kimpo University in the Republic of Korea, University of Sofia in Bulgaria and the University of Porto in Portugal. The comprehensive results of these tests are summarized below.
Exploring the Advanced Sensor Technology in Ecosense Radon Detectors
At the heart of all Ecosense products is its unique radon sensor technology, a pulsed ion chamber whose output is processed by patented ultrasensitive detection circuitry and algorithms (U.S. Patents #10,132,936 and #11,169,281). The radon sensor used in the professional products, RadonEye, and EcoQube provides 30 CPH pCi/L (counts per hour per picocurie per liter) sensitivity, the highest in the industry. To achieve its compact form factor, the EcoBlu uses a smaller ion chamber of 18 CPH pCi/L sensitivity. All Ecosense products provide an updated reading every 10 minutes.
The ion chamber radon sensors used in Ecosense products are so uniquely fast, that the company can provide options for the radon-based duty cycle control of Heat Recovery Ventilators (HRVs), an emerging option for, in certain circumstances, low-cost and minimally invasive home radon mitigation projects.
Third-Party Validation Studies
University of Michigan
In 2019, a study was performed by the Department of Nuclear Engineering and Radiological Sciences at the University of Michigan (Ann Arbor, MI) in which the RadonEye was compared to the AlphaGuard professional radon monitor from Bertin Technologies (Montigny-le-Bretonneux, France) [Ref. 1]. The AlphaGuard was selected from other professional-grade monitors to be the “gold standard” based on its highest manufacturer-reported accuracy. Per the researchers, it was then priced at ~$10,000.
In this case, the radon chamber was an underground room that proved to maintain a remarkably constant radon concentration. With the addition of radon sources over and above the high natural background, levels characterized as 1,100-1,500 Bq/m3 (29.7-40.5 pCi/L) were thus studied. Radon levels were monitored by each of the following professional grade radon monitors: the Pylon AB-5 from Pylon Electronics, Inc. (Ottawa, Canada), the Sun Nuclear Model 1027s and Model 1030 from Sun Nuclear Corp. (Melbourne, FL), the Durridge Rad7 from Durridge, Inc. (Billerica, MA), and the Femto-Tech CRM-510 from Femto-Tech, Inc. (Carlisle, OH).
University of Michigan Comparison of Ecosense’s RadonEye and Saphymo’s AlphaGuard
The graphic depicts RadonEye's accuracy at par with AlphaGuard in the University of Michigan study. Notably, two quotes stand out:
“RadonEye was identified as a likely candidate for other experiments due to its strong performance, low price tag, ability to record measurements over set time intervals, and the ability to extract data using only a smartphone.”
“The ease of use of RadonEye is another feature that makes it desirable for use. It is merely plugged into an outlet and all the data can be extracted with a cell phone using their app.”
Kansas State University Radon Chamber
Kansas State University personnel performed a 72-hour study at the Kansas State University Radon Chamber (Manhattan, KS) with settings at 10-20 pCi/L (Day 1), 55-65 pCi/L (Day 2), and 25-35 pCi/L (Day 3), as monitored by a Pylon AB-5 [Ref. 2]. Three sets of five each of the following consumer devices were tested: RadonEye, Airthings Wave, and Airthings Wave Plus.
Significant differences were found between the values reported by the units tested. Expressed in a simpler way, in the case of what should be steady-state radon levels, both Airthings Wave devices will often display a value outside of the typical range of variation of the RadonEye. The graphic below shows an example of this testing comparing the IRE of the RadonEye and the Wave devices versus the Pylon AB-5.
University of Kansas Comparison of Hourly Trends
The figure below provides an example of a systematic difference in the pCi/L hourly data provided by a representative subset of the devices studied. Given that the RadonEye provides a new 1-hour average every ten minutes and the Wave devices produce a new 24-hour average every hour, it is understandable that there is a lag of several hours (in figure below clearly a day) in fully responding to changes in radon level. If one desires to quickly survey a number of locations within a home to decide upon where to set-up long-term testing, such a lag does present an issue. In a laboratory environment where the level of radon is kept constant, such lag times may be irrelevant; however, in a practical environment where radon levels often fluctuate wildly, RadonEye products from Ecosense likely provide more accurate initial measurements.
University of Kansas Comparison of Response to Changes in Radon Concentration
Decision making on radon mitigation projects should be made on the basis of long term multi-seasonal testing; however, there is value in short term data. If trends in short-term data may be visualized on one’s smartphone, it is increasingly likely a consumer may be able to correlate high and low values to at least indoor/outdoor temperature differential and ventilation behavior. Depending upon the interest a consumer takes, it is entirely possible to get into the habit of turning on ventilation or cracking open a window or two when readings creep higher.
In 2016, a study was performed at Kimpo University (Gimpodaehak-ro, Republic of Korea) in which the RadonEye was compared to the Rad7. [Ref. 3] The radon chamber used was a small outdoor building of ~10 m3 volume designed to simulate single story residential construction methods (including a peaked roof and a conventional door and window). The negative pressure effects of diurnal temperature changes produced a draw on an externally ducted solid source producing radon by radioactive decay.
Kimpo University Comparison of Ecosense’s RadonEye and Durridge’s Rad7
Over a period of ~500 hours, radon concentrations varied over the range of 10-500 Bq/m3 (0.27-13.5 pCi/L). The graphic above shows that RadonEye was able to essentially read identically to the Rad7 (then, per the researchers, priced at ~$8,000). The area circled corresponds to rising and falling radon levels across the U.S. and Canadian recommended thresholds for homeowners to make remediation decisions.
Testing of 36 RadonEye detectors was performed at Sofia University (Sofia, Bulgaria) with the participation of the French primary metrology laboratory LNE-LNHB (Laboratoire National Henri Becquerel, Paris-Saclay) [Ref.4]. This work concluded the devices “appear to have a linear response for 222Rn concentrations below 3,500 Bq/m3” (94.6 pCi/L).
The work was performed at Sofia University using a 200 L chamber using an AlphaGUARD PQ2000 PRO (Bertin Technologies, Montigny-le-Bretonneux, France) as a reference radon monitor with two additional monitors present. These two were an AlphaE (Bertin Technologies, Montigny-le-Bretonneux, France) and a RAD7 (Durridge, Inc., Billerica, Massachusetts, USA). The study concluded:
“Overall, the results show that the RadonEye instruments are very suitable for continuous radon monitoring and may be useful for follow-up of radon dynamics in long-term measurement campaigns in homes and workplaces.”
The University of Porto
Members of the Faculty of Engineering at the University of Porto (Porto, Portugal) performed a comparison of the RadonEye RD200 and the RadonEye RD200P2 versus the Airthings Wave in five nursery or primary school classrooms [Ref. 5]. The performance of these detectors was referenced to the Radim 5B, a research grade instrument from SMM (Prague, Czech Republic). The study concluded as follows:
“The present study concluded that, in schools, the studied RadonEye low-cost sensor devices (RD200 and RD200P2) had behavior similar to the reference instrument (Radim 5B) while the Airthings Wave behaved differently. Accordingly, RadonEye devices presented better performance indices (R2 and RMSE) than the Airthings Wave, both during the entire period and considering only the occupancy period. Thus, these RadonEye devices seemed to be more suitable for real-time short-term radon monitoring, detecting peak concentrations with high accuracy.”
The plot taken from the University of Porto study, above, displays radon concentrations in three classrooms testing Airthings Wave and Ecosense’s RadonEye Models RD200 and RD200P2 versus the Radim 5B.
Though sensitivity data appears sparsely in the commercial literature, the sensitivity of semiconductor-based consumer radon monitors (Corentium Home, Airthings Wave, SunRadon Luft) is believed to vary between 0.9 and 1.3 CPH/pCi/L. This is significantly below the 30 CPH/pCi/L of all Ecosense’s products but the EcoBlu (which boasts a respectable 18 CPH/pCi/L). This sensitivity advantage is clearly seen in the University of Porto’s results.
Ecosense Radon Detectors for Consumers
Ecosense provides a range of continuous radon monitors designed for both consumers and professionals. The consumer-focused products include EcoBlu, EcoQube, and RadonEye, each with unique features tailored to meet varying customer requirements.
EcoBlu is a reliable, standalone digital radon detector that does not require Wi-Fi or Bluetooth connectivity. This device provides short or long-term average readings directly on its display without the need for a mobile app. Users will be alerted with audio or visual alarms, displayed in red color, if their radon reading exceeds the recommended action level set by the EPA or customized by the user. EcoBlu is an excellent option for continuous radon monitoring.
EcoQube is a cutting-edge continuous radon monitor that has won multiple awards for its intelligent features. With Wi-Fi connectivity, you can easily access your radon data from anywhere at any time. The device is equipped with an LED color indicator, which guides you on whether your radon level is low (Green), moderate (Orange), or high (Red), ensuring that you are always aware of any potential health risks. The EcoQube App provides you with a smart view of real-time readings and long-term radon trend charts for comprehensive analysis, making it easier for you to identify any patterns and take appropriate action to ensure your safety.
RadonEye is Ecosense’s first-generation radon detector that uses BLE connectivity to display real-time radon levels on its OLED display. With its ability to update every ten minutes and provide a rolling one-hour average of its last six measurements, it ensures that users stay informed about the presence of radon gas. Additionally, the detector continuously scrolls daily and monthly averages across the bottom of the OLED display, making it easy for users to track trends over longer periods of time. For a more in-depth analysis of the accumulated data, users can download the RadonEye App (available for both iOS and Android) to access a graphical visualization of all the data right on their smartphones.
Overall, all Ecosense home radon detectors are smart and reliable solutions for anyone looking to monitor radon levels in their home or workplace. Detectors may be purchased directly on the Ecosense website or at the Ecosense Amazon Store.
Ecosense Radon Detectors for Professionals
In addition to consumer products, Ecosense also offers advanced continuous radon monitors, such as RadonEye Pro and Ecotracker, designed for professional use.
RadonEye Pro is a professional-grade product, designed for use by home inspectors and radon testers. This product features both Bluetooth (BLE) and Wi-Fi connectivity. BLE is used for set-up, registration, device control, and data collection via the smartphone app. After set-up, data is posted via Wi-Fi to the Ecosense cloud, which may then be accessed from either one’s desktop or mobile devices. In general, we find professional inspections are most commonly scheduled for either 48 or 72 hours; however, RadonEye Pro can be set for timed inspections of any length. Once a timed inspection is set, an embedded accelerometer is able to tell whether the results have become invalid due to any movement of the device. The software provided allows for generating inspection test reports in a convenient .pdf file format. Once the testing location is input, the template provided is customized to individual state reporting requirements. Alternatively, a .csv (“comma separated values”) file can be directly opened into an Excel spreadsheet which may be integrated into an inspector’s own reporting templates.
RadonEye Pro is National Radon Proficiency Program (NRPP) listed (in the USA) and C-NRPP listed (in Canada). Calibration may be performed through support relationships Ecosense has in place with Bowser-Morner, Inc. and the KSU Radon Chamber for U.S. users and, for Canadian users, the Radiation Safety Institute of Canada. Annual calibration is required to maintain certification.
EcoTracker is a bundle of four radon detectors designed to be used together to rapidly “sniff” the location of radon “hot spots.” It is meant to greatly reduce the time involved in characterizing a home as a part of planning a mitigation strategy. Using purpose-built software, all four devices simultaneously report to the professional’s smartphone or other mobile devices.
One manner in which Ecosense radon detectors are complementary is that, in the interest of peace of mind, we suggest one of the consumer products can be a "leave-behind" after radon professionals perform testing and/or mitigation work. This would ensure the quality of your work and continuous radon monitoring can be offered as a subscription service with the EcoQube's remote features.
While the widely trusted Consumer Reports Organization (Yonkers, NY), a non-profit, has produced articles comparing radon detection products in the now-distant past, these predate the general consumer availability of continuous radon monitors. Their past test programs thus focus on passive detection approaches such as plastic chip track detectors and carbon absorption cartridges, both of which must be sent away for laboratory analysis after exposure. Ecosense continues to lobby Consumer Reports for an updated study to include electronic radon monitors. Help us if you can.
Unlocking the Importance of Third-Party Testing: Why It Matters to You
To date, four third-party cross-comparative studies have confirmed that Ecosense’s RadonEye products are as accurate as professional-grade radon test equipment priced many times higher. Nothing is sacrificed if one opts for the more economical radon measurement solutions from Ecosense. Importantly, the high sensitivity of all Ecosense products, 30 CPH pCi/L for each but the EcoBlu (which is a very respectable 18 CPH pCi/L), allows for the update of data in 10-minute intervals.
With Ecosense products one can not only perform an accurate test quickly but, with minimal additional time invested, one can also determine the best place to test.
Of course, decision-making on radon mitigation projects should be made on the basis of long-term multi-seasonal testing; however, there is value in short-term data. If trends in short-term data may be visualized on one’s smartphone, it is increasingly likely a consumer may be able to correlate high and low values to at least indoor/outdoor temperature differential and ventilation behavior. Depending upon the interest a consumer takes, it is entirely possible to get into the habit of turning on ventilation or cracking open a window or two when readings creep higher.
Remember, if concerning radon levels are ever persistently found, the consumer’s best next step is to call in their certified radon professional.
1. M. Carmona and K. Kearfot, Intercomparison of Commercially Available Active Radon Measurement Devices in a Discovered Radon Chamber,” Health Physics, 116 (6), pp 852-861, 2019
2. B. Snead and B. Hanson, “Kansas State Radon Chamber Ecosense Consumer Device Comparison,” unpublished private communications
3. Kyungbuk Park, “Comparison of RadonEye and Rad7,” Kimpo University, unpublished private communication
4. Mitev K., Georgiev S., Dimitrova I., Todorov V., Popova A., Dutsov C., & Sabot B. (2022). Recent work with electronic radon detectors for continuous Radon-222 monitoring. Journal of the European Radon Association, 3
5. Sá, J.P., et. al, Radon in Indoor Air: Towards Continuous Monitoring, Sustainability, 14, pp. 1529, 2022
Author Peter Foller
Peter C. Foller is a highly accomplished chemist and former R&D director for PPG Industries, where he led research and development for Transitions Optical. He holds a Ph.D. in chemistry from the University of California at Berkeley and is a named inventor on 50 U.S. patents. After retiring from PPG, he served as CEO of Acutect, Inc. and is an active member of Keiretsu Forum. Dr. Foller currently serves in board and advisory capacities with several San Francisco Bay Area technology start-ups, including Ecosense Inc., and volunteers with the Clean Tech Open.