GQ Electronics RadonScan

GQ's user guide says the RadonScan uses a high-sensitivity GQ Radon Gas Sensor: as radon gas passes through the sensor, it triggers an electrical signal that the device's processor registers. That is the whole description. GQ does not say what kind of detector it is (a pulsed ionization chamber, an alpha spectrometer, a semiconductor sensor or something else), or whether air reaches it by passive diffusion or with a pump, so the sensor type and the sampling method are not stated by the maker. The guide lists Rn222 as the radon it registers and a range of 0.00 to 100 pCi/L (0.00 to 3700 Bq/m3).

GQ says radon data are collected continuously, with the measured data passed to the processor every second, and that readings are logged into internal memory (1M bytes of flash) every second, so the stored data survive when the unit is turned off. The guide says the device shows the background radon level within about 5 minutes of power-on, adds that readings vary with time and place, and recommends averaging readings over a longer period for the most accurate results.

The main screen carries four averages in pCi/L: 1 Hour, 1 Day, 1 Week and Long-Term. One key switches between hourly, daily, weekly and long-term display modes and another switches the radon unit between pCi/L and Bq/m3; the guide also says the value can be converted to Working Level. A clock can be set from the menu. GQ's Reset Data option clears the stored hourly, daily, weekly and long-term data and starts fresh.

GQ's specification table gives no accuracy figure. The only figure near it is a line that reads "Reproducibility of indication" with the value 30%, with no radon level or test period attached. GQ does not explain the line further, gives no accuracy against a reference radon level and publishes no sensitivity in counts per hour, so we do not turn the 30% into an accuracy claim.

For alerts, GQ lists front and rear LEDs and a buzzer. The LED shows green for normal readings, yellow for medium and red for high, and can be turned off. The alarm level can be set from 0 to 99 pCi/L, the alarm sound turned on or off, the beep volume changed, and a menu item picks which reading triggers the radon alarm. Pressing any key while the alarm sounds silences the beep until the reading drops below the threshold or the unit is powered off.

The RadonScan has no wireless link. GQ's guide says the RadonScan-Plus and RadonPro offer Wi-Fi and can send data to GQ's GMCmap server, and that the GMCmap phone app is for the RadonPro; the RadonScan's Type-C USB port carries power and data communication. GQ calls the RadonScan an open application protocol product and invites users to write their own software on its GQ-RFC2401 protocol. GQ's downloads page offers a Windows RadonScan simulator, which the guide describes as a one-to-one copy of the device's interface.

The menu also has a Radon Auto Calibration screen, which GQ says is for advanced users or professionals: it calibrates the unit against known radon levels (GQ suggests 0, 4 and 25 pCi/L) and works out counts per hour, and a Radon Hardware Calibration that takes 1 to 2 minutes. GQ does not say how the RadonScan is calibrated before it ships. Its documents also give no operating temperature or humidity range; beyond the cautions in the setup section, operating conditions are not stated by the maker.