Frequently Asked Questions


What is the geiger counter?

Our geiger counter detects ionizing radiation such as alpha particles, beta particles and gamma rays using the ionization effect produced in a Geiger tube/sensor.

How do I know the unit model?

Please hold the on button for 3 seconds and you will see the model information on the screen.
The model is also marked on your package.

What is the safe range of the reading?
CPM uSv/h mR/h Meaning
5-50 0.03-0.33 0.003-0.033 Normal background
51-99 0.33-0.65 0.033-0.065 Medium Level Radiation
>100 >0.65 >0.065 High Level
>1000 >6.5 >0.65 Very High Level
>2000 >13 >1.30 Extremely High Level
What can it detect ?

Geiger counter can be used on real-time testing evaluation, scientific testing on sample like: Building Material, Hospital Radiation Therapy Monitoring for Cancer, Food, Water, Indoor/outdoor,X-Ray, and more..
There are three type of radiation, Alpha, Beta and Gamma.
Alpha doesn't travel far from the source and is a weak type, can't pass through 1 piece of paper or the first layers of skin.
Beta, lasts longer than Alpha and can pass though multiple layers of skin.
Gamma is the worst. It's the type used in radiation therapy, Neutron is the last. Reference

Any specific examples of what and where to detect?

  • Alert you once big incident happens: like dirty bomb, Fukushima, Chernobyl.
  • Carry the unit with you to test air, food, water, personal environment.
  • Lab research, oil field, hospital radiation treatment.
  • Nuke plant environment radioactive plume like Fukushima.
  • Stone collection, marble counter-top, building material, antique collector.
  • Space radiation, air industrial.
  • Hospital Radiation Therapy Monitoring & Radio iodine Treatment Monitoring.
  • Real-time testing evaluation, scientific testing on samples.
  • Measuring on Antique radiation level like Vintage Fiesta Dinning Ware.
  • Space Radiation Detection on the airplane.


For how long the unit works on a single charge?

The device will work about 2-3 days on a 100% charged battery with Power Saving mode on.

How do you charge this unit?

The GMC units can be charged by any standard USB power adapter, even a computer USB port. You can just connect the USB cable to any USB port.

Is the battery a standard battery that can be purchased anywhere or is it proprietary? How does one remove the battery?

When you receive the unit, the unit comes with a rechargeable battery and you can charge your unit with the USB cable in the package. You can remove the battery by simply open the battery case.

Can this be plugged into an AC power supply or is it battery only?

It can be plugged in to an AC power supply, and it can stand with battery.

Software & GMC Map

Is the software compatible with Windows 10? Is there a software for Mac OS?

Yes for Windows. No for Mac OS.

How should I use the iOS app, GMC Data Viewer?

Download it from app store and if you are a existing user with our GMC Map, your account/Geiger Counter information is saved.
If you are a new user, please click "Add" on your Geiger Counter Category. Then follow the tutorial.

Can you add some functions to GMC Map?

Yes we are always happy to improve! Please post in the forum or write us an email.


What is the biggest difference between model-X and model-Y?

Please click "compare" on each item or check the comparision table.


Does the product come with any calibration certification?

The unit has been calibrated during the production and QA process. There is no paper based certificate in the package.

There is a calibration option in the unit menu. A standard radioactive source is used to calibrate the unit. The unit has been calibrated from the manufacture. So, you do not need to calibrate it again if you use it as regular measurement.


What kind of support service do you support?

Besides eBay/Amazon warranty, we also offer one year factory warranty as the manufacturer
Before you buy, please check GQ Geiger Counter Selection Guide and try the exact copy of GMC demo software before you get it.
We provide future free download firmware update and GQ online support forum.