SIRA – Aerosol Monitoring


SIRA is ENVINET’s solution for the automatic, ongoing monitoring of airborne activity concentration. The system’s data interfaces and transmission paths are identical to those of the SARA spectroscopic dose rate probe. As SIRA can be integrated in existing and new NMC monitoring networks, it is the perfect complement to dose rate probes in monitoring networks.

SIRA consists of a collecting unit, through which the ambient air is drawn. The particles contained therein are separated via a filter. While the particles are being collected, the detector above the filter monitors them for radioactive components on an ongoing basis. The readings can be accessed online at any time. With its automatic switching mechanism, the filter magazine enables the maintenance-free operation of the system for 30 days (60 is also available as an option). SIRA can thus also be operated at remote, unmanned stations. The filters can also be removed individually at any time before the entire stack of magazines are processed (e.g. in the case of unusually high readings) for evaluation in the laboratory.

The detector is a trusty SARA spectroscopic gamma probe. The filter activity is then subjected to spectroscopic analysis. This makes the nuclide-specific activity available, in addition to the total activity concentration.


  • Nationwide networks
  • Ring monitoring around nuclear power plants
  • Area monitoring


  • Detector: NaI(Tl) or optional CeBr3
  • Internal heating of sampling pipe
  • Gamma nuclide activity evaluation for each spectrum according to ISO11929
  • Freely configurable nuclide library
  • Flow rate: 0.3 – 7 m³/h
  • Filter size: 47 mm
  • Filter magazine for 30 or 60 days’ autonomous operation.
  • Compact size, small footprint
  • Low energy consumption