R4000 radon probe

NanoSense R4000 header

The R4000 probe measures the volume activity of radon in air to restrict its concentration in buildings. This is a RS485 ModBus probe which can work independently or work as slave of the E4000 air quality probe to be integrated in the intelligent management of the low-energy buildings (LEB).

The RT2012 regulations require airtightness for low-energy buildings, therefore internal air renewal can only by performed by HVAC. Airtightness can increase the concentration of the radon in a significant manner.


How the radon enters your house

For most individuals radon is a main source of the natural background exposure (59 %) and represents about 40 % of radiation exposure from all radiation sources (natural + medical + others). Radon is an invisible, odorless, radioactive gas, result of the disintegration of radium (Ra-226), which is a decay product of uranium (U-238), naturally occurring in the Earth crust. The radon can be released to soil pores, migrate to the ground surface and accumulate in buildings. Radon and its short-lived progenies polonium (Po-218), and (Po-214) settled in the respiratory tract give rise to high doses to lung tissue from alpha particle radiation which they emit. This can effect in lung cancer.

  • In France, about 3000 cases of lung cancer death per year (12 % of all deceases due to lung cancer) are attributed to the domestic radon exposure.
  • 43 % of the individual houses are exposed to radon concentration ≥ 100 Bq/m³ and 10.8 % to radon level ≥300 Bq/m³.
  • Respectively 21.5 % and 2.8 % for all the collective accommodation


31 French departments are the object of regulations concerning the implementation of corrective actions to reduce the radon exposition in public places .

Radon concentration [Bq/m³] Risk of lung cancer.(+,++,+++)
< 100 small
100 - 400 + , corrective actions
400 - 1000 ++, corrective actions
> 1000 +++, corrective actions
Radon in France


The radon level of 300 Bq/m³ should be considered as a first stage of the management of radon problems, with a long-term objective to lower this level to 100 Bq/m³.

The indoor concentration of the radon depends on the natural activity of the soil, on building materials, on the type of building (living space, Canadian well), habits of life (heating, aeration) and weather forecast. It is common to find up to 10 times different radon concentrations in 2 neighboring identical buildings.

The radon concentration, in the same place, can vary by factor from 10 to 100 according to the period of the year and the hour of the day. To follow the temporal evolution of the volume activity of radon, the method of measurement must be adapted to the dynamics of the phenomenon.
To optimize the detector response-time and sensibility, the R4000 radon probe uses a solid state sensor to measure the activity of the decay products of the radon. Applied alpha spectrometry technology allows categorizing descendants with short half period between (Po-218, Po-214) and long half period (Po-210). Thanks to the short time of radon concentration measurement, quickly adaptive strategies to the dynamics of possible changes of the concentration of radon in buildings can be applied.

The R4000 probe

Continuous measurement of the radon concentration and in case of the overtaking of regulation level, different strategies of radon remediation are implemented, such as:

  • Mechanical air renewal.
  • Over pressurization of the building.
  • Bypassing the ventilation air intake by the Canadian well. In fact the radon can seep through by Canadian well and notably by its sump.

The application of these strategies of remediation allows to bring down the average concentration of radon, to acquire a quality of the air guaranteeing comfort and health on long term.

If the R4000 probe is connected to the E4000 air quality probe, the measurements and the commands for the remediation can be send by KNX or LON, even by radio or standard EnOcean.
The R4000 probe can also be connected to the network via RS485 ModBus and can have 10 selectable addresses.
Sober and discreet design of the probe allows easy integration in refurbishing as in new buildings.


Available soon