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What if
you could forecast earthquakes?

What if
you could forecast

Earthquakes can be forecasted up to 10 days before the first shakes by measuring radon variations in soil.

RadEQ is a connected device that monitors radon activities in soil. It measures, collects, analyses data and sends alerts in real-time.


Easy to set up

1. Background

The radon emission from soil is known since 1920’s but the use of data for earthquake prediction only started in the late 50’s. Several studies have been conducted by geophysicist all around the world.

The pioneer Hatuda has shown in 1953 the relation between radon anomalies and a magnitude 8 earthquake in Tonankai, Japan.

In 80’s, R.Igarashi, an other Japanese scientist, studied with his team groundwater radon for about 20 years. On January 7th 1994 they recorded a sudden increase and decrease of radon concentration in soil. Seven days after this significant anomaly, a magnitude 7.2 earthquake hit the city of Nishinomiya.

Radon concentration – Nishinomiya city, Japan [from Igarashi et al., 1995]

Precursory phenomena of radon in earthquake sequence were then observed in India, Syria, Turkey, Italy and more. According to R.D Cicerone et al. (2009), 83% of the observations reported that radon levels increased prior to an earthquake (relative to the background radon levels).

In 1991, the IAEA organisation published a report about the possibilities to forecast earthquakes. They concluded that radon gave very good result as earthquake precursor in ground: “Radon 222 seems to be one of the most promising precursors and is the tracer for which more data are available: according to statistics elaborated in China, 70% of earthquakes are preceded by radon anomalies detectable in soil, air and/or in groundwater.” They based their report on many studies and observations from their member or from independent research; The IAEA member V.T. DUBINCHUK wrote: “After more studies and continuous monitoring, an apparent correlation between the changes of radon concentration in groundwater and successive after-shocks was confirmed.

An other correlation has been found by N. SEGOVIA, S. DE LA CRUZ-REYNA and M.A. ARMIENTA-HERNANDEZ of the Institute de Geofisica de Mexico: “The evidence that radon concentration in soil gases undergoes significant changes in correlation with volcanic activity is growing rapidly.” Ref: IAEA-TECDOC-726

More recently, in 2011, before the M9 Tohoku Earthquake, satellite and ground anomalies observations of the Ionosphere were detected. In a report, the NASA indicated that the radon emission from the ground before the earthquake was so important that it had for consequences to ionise the Lithosphere- Atmosphere- Ionosphere around the epicentre. “Briefly, the primary process is the ionization of the air produced by an increased emanation of radon (and other gases) from the Earth’s crust in the vicinity of active fault (Toutain and Baubron, 1998; Omori et aI., 2007; Ondoh, 2009). The increased radon emanation launches the chain of physical processes, which leads to changes in the conductivity of the air and a latent heat release (increasing air temperature)

2. Why Radon?

Scientists tried to detect anomalies from many geo-gases emanations around seismic zones all over the world as Helium, Radon, Hydrogen, Carbon dioxide, Methane and more. However, radon is preferred for many reasons:

  • It has a short half-life, that allows to detect short term changes
  • It is easily detectable as it is a radioactive gas

We, at AYKOW, are specialized in radon sensor designing. We created innovative devices in order to mitigate radon in buildings and our dwellings. Our last radon controller named Radostat already performs in Americans, Canadians and Europeans places.

We quickly understood under the guidance of geophysicists that our efficient technology of radon detection could do more! It can indeed overcome problems that scientists experienced during their observations of radon as earthquake precursor:

  • RadEQ is an active device while most of traditional ones are passive. It allows short-term and continuous measurements, long term use and online reading.
  • RadEQ sensor features very low-energy consumption. It can be self-powered by solar energy.
  • RadEQ is equipped with a GPRS module. It can be placed near any fault, even in the desert.

Last but not least :

  • RadEQ probe is much cheaper than any other existing radon monitoring device in the world. That significantly reduces the cost of an in-soil radon monitoring network as never before.


Power supply : Solar panel
Sensitivity : 15 pulses/hour for 1000Bq/m3
Wireless : 300meters – Adjustable Frequency. Every 4 hours Data transfer
Size : Ø50 x 60mm + 80x80x50mm
Weight : 200g

Working Temperature : -10°C To 50°C


RadEQ App and web service

A dedicated app and a web service allow the user to view all the information collected by the device along with any risk alert. They also give access to our global data network, extended analytics, earthquake maps and more.

Download the RadEQ brochure


Any question?