Radon and Indoor Air Quality  

Radon is an odorless, colorless radioactive gas. Unlike other noble gases such as Helium and Neon, Radon gas remains closer to the ground. Radon breaks down into solid radioactive elements called radon progeny (e.g., Polonium-218, Polonium-214, Lead-214). Radon progeny can attach to dust and other particles and can be breathed into the lungs. As radon and radon progeny in the air break down, they give off radiation that can damage the DNA inside the body’s cells. Radon is normally found at very low levels in outdoor air and in drinking water from rivers and lakes. It can be found at higher levels in the air in homes and other buildings, as well as in water from underground sources, such as well water.

Visit theEPA websiteor contact a Radon or Indoor Air professional in your area to learn more about Radon.

A Volatile Organic Compound (VOC)is defined as any compound containing carbon that can be readily vaporized, except methane. VOC's, measured in totality of its mixed gases indoor environments from cleaning and disinfecting products, paints, wood preservatives, carpeting, building materials, aerosols, insect repellents, microbial growth, and a host of other sources

At elevated levels, VOC's can cause eye, nose, and throat irritation; headaches, loss of coordination, nausea; damage to liver, kidney, and central nervous system. Some organics (such as Benzene) are suspected or known to cause cancer. Key signs or symptoms associated with exposure to elevated levels of VOC's include eye infections and irritation, nose and throat discomfort, headache, allergic skin reaction, shortness of breath, signs of poisoning, nausea, vomiting, nose bleeding, fatigue, and dizziness.

According to Indoor Air Quality standards such as the WELL Building Standard and the US Green Building Council (USGBC), VOC levels are considered elevated above 300-500 microgram/m3. Depending on the mix of the VOC's and their individual molecular weights that can be translated to about 200 - 450 ppb (parts per billion); OSHA does not generally regulate the total combination of VOC compounds; rather regulates limits for some specific VOC compounds

Carbon dioxide (CO2)equivalents, or short eCO2, are derived from the measurements of the mixed gases, tVOC's, and describe the quality of indoor air in equivalent units of CO2. Traditionally indoor air quality is limited to the measurement of temperature, humidity, and carbon dioxide alone. eCO2, however, follows increasing CO2 levels but also contains information about additional harmful mixed gases and odorous events, while a CO2 sensor detects just the exhaled CO2 from the room’s occupants.

396 ppm (parts per million) was the mean average annualized global outdoor CO2 level reported at the end of August 2013 by NOAA. OSHA states that 1,000 ppm should be used as an upper limit for indoor levels, as a guideline for occupant comfort; a level higher than 1,000 ppm indicates inadequate ventilation. EPA testing recommends Carbon Dioxide levels to not exceed 800 ppm. American Society of Heating Refrigeration and Air Conditioning Engineers (ASHRAE) and the American Society of Testing and Materials (ASTM) suggest indoor levels should not exceed 700 ppm and 650 ppm above outdoor air, respectively. At levels above 2,000 ppm for an extended period of time complaints such as headaches, fatigue, and eye and throat irritation are typical and more widespread.

Relative Humidity (rH) is among the most common of indoor air environmental factors implicated in occupant discomfort. Elevated humidity has been shown to be associated with a worsened perception of Indoor Air Quality. High %rH is also an indicator of conditions favorable to mold and microbial growth.

ASHRAE (American Society of Heating Refrigeration and Air-Conditioning Engineers) recommends a maximum of approximately 56%rH at 80°F and up to approximately 86%rH at 67°F (at standard atmospheric pressure). Clothing, radiant heat and many other factors influence the recommendations of this standard. This is based on their standard Graphical Comfort Zone Method. Per ASHRAE there are not any established lower humidity limits for thermal comfort. However, non-thermal comfort factors such as skin drying, irritation of mucus membranes, dryness of the eyes, and static electricity generation, may place limits on the acceptability of very low humidity environments.

The latest version of the lüft™ app includes a Mold Risk Indicator. The app analyzes the CURRENT condition of temperature and humidity and determines how likely it is to develop mold. The Mold Risk is provided on a 5 level scale from very low to very high risk. Very low risk means it would take more than a year at this condition to develop mold, if any. Very high risk means it would only take less than 3 days to develop surface mold. Note of caution: the device does not measure mold but indicates risk of developing mold. Also, other surfaces in the house; like windows, outside walls; may show mold even at lower risk levels. That is due to the local temperature and humidity index on that window or wall, which can be drastically different than what is measured in open air. 

The latest version of the lüft™ app also provides an outside Air Quality Index or AQI. The AQI is a measure of how clean or polluted the outside air is, and what associated health effects might be a concern. 

When your lüft™ monitor reports Radon levels above 2pCi/l for extended periods of time, please, contact a Radon Inspection and Mitigation professional. When VOC or eCO2 levels read high repeatedly, contact a certified Indoor Air Quality professional to seek advice or perform additional testing. Improving home ventilation will temporarily mitigate the health concerns but does not address a potential underlying issue as to why levels read high.

 lüft™ Setup and Use Questions

Your lüft™ Monitor will start up again as soon as power is restored. The monitor saves all settings and data for up to 4 years on the device. Upon power up it will reconnect to your Wi-Fi network, restore all custom settings, and continue to measure your Indoor Air Quality as before. After a power interruption the first hourly date reading may be delayed up to 90 minutes. However, ad-hoc readings can be retrieved at any time before that.

Yes. The lüft™ Monitor has been certified by Intertek to be compliant to UL and CSA safety standards 61010-1. During that certification, the device went through rigorous safety testing performed by an independent, certified laboratory. In addition, Intertek audits our manufacturing facility quarterly to maintain that certification. The device was also tested by an independent, certified laboratory to be compliant with Proposition 65, officially known as the Safe Drinking Water and Toxic Enforcement Act of 1986.

Unlike our Radon, Temperature, Humidity, and Pressure Sensors, the sensor measuring VOC and CO2 equivalent is a relative sensor. A relative sensor measures changes in levels with very high precision but does not report absolute levels. The built-in logic performs periodic self-leveling to compensate for any long term sensor drift or sensor aging. That enables these type of sensors to measure very small changes in VOC levels, which are measured in parts per billion. The latter is essential to detect deterioration in air quality. Most if not all VOC sensors in consumer Indoor Air Quality devices work based on the same principle. For questions, please contact your local Indoor Air Professional.

Yes, the monitor has a UL compliant, auto-ranging power supply rated for 120-430V and 50-60Hz. However, at this time the device is only certified to be used for 120V, 60Hz applications, i.e. any common US standard wall outlets.

Your lüft™ monitor does not require calibration. There are also no internal batteries and no other serviceable parts.

It is recommended to have at least one monitor in each of the main living and sleeping quarters.

You can securely share each individual monitor's data by entering the e-mail of your trusted Radon or Indoor Air professional under "share data" in the individual device menu. Once enabled, your trusted professional can review and monitor your data in real time but has no access to your monitor, your mobile app, or your phone, i.e. it's an at-will data sharing only feature.

The Temperature Offset function lets you adjust the temperature calibration by up to +/- 5F. This is useful if you like to synchronize multiple lüft monitor readings or match the readings of your HVAC system. All temperature sensors, including HVAC thermostats, lüft monitors, or any other indoor device, can only measure the temperature of their immediate surroundings. Temperatures in rooms vary based on air-flow, ventilation, position in the room relative to heaters and HVAC outlets, and other factors. Because temperature and relative humidity are not independent, an adjustment of the Temperature Offset in a lüft monitor will also adjust the relative humidity accordingly.

Your lüft™ Monitor will display your Indoor Air Quality status. Green means Okay, all is well! Yellow means that at least one of the 6 sensors is at or beyond its Warning threshold. Red means at least one of the 6 sensors is at or beyond its Alert threshold. If you also enabled the Nightlight function, the device will show blue during the night. Advanced users can change all threshold values and color definitions as well as brightness, i.e. choose a different color or brightness at your choice for each state (Ok, Warning, Alert, Nightlight) and adjust thresholds for each individual sensor to meet your needs.

The Altitude Correction automatically adjusts the measured atmospheric pressure to sea level. This allows the comparison to the atmospheric pressure commonly reported by your local weather stations (Radio, TV, or Internet). You can disable this feature in Settings>>Thresholds>>Air Pressure.

To reset your device press the blue button on the side of the monitor until the LED starts blinking and then release the button. The reset will remove all sensor and user specific data from the device and return all settings to their default values. If you like to reconnect to the device, please, make sure to remove that device from your phone's Bluetooth list prior to connecting again.

When adding a new device to your account the device uses the following default warning and alert thresholds:


lüft™ can be connected to any 2.4GHz WiFi network. Any common "Dual Band" home WiFi router or hub supports both, 2.4GHz and 5GHz. Most routers manage the assignment of 2.4GHz or 5GHz automatically and you simply connect to the available network provided by your router. Some routers do provide two networks with 2 different names where one of them often has the label  "5G" in the name. In this case, select the network that does not have the "5G" in the name. When not sure, please, see the router label on the bottom of the router or the manual for further guidance.  

During the account and device setup, the app asks for permissions to use your Bluetooth access, to enable Notifications as well as location service. These permissions are required to connect, setup, and use the device properly. If you accidently denied any of these permissions or want to see what other permissions are set, please, navigate to your phone settings, look for the lüft app and open it. Depending what type of phone you have the permission screen may look like the screen below. Verify that location is enabled "while using" and Bluetooth and notifications are enabled as well.  

To install this Web App in your iPhone/iPad press and then Add to Home Screen.