Long-term measurement is reliable and gives and annual average value. The measurement must span over at least 60 days during the heating period, i.e. October 15th – April 15th. Long-term measurement gives you an answer as to what radon levels are present in the residence/amenity. It is also the recommended method by the Norwegian Radiation and Nuclear Safety Authority (DSA). Long-term measurement must be performed with at least one detector per floor and always with a minimum of two detectors. The detectors must be placed in furnished rooms (e.g. bedroom, living room, den) - rooms such as bathrooms, laundry rooms do not count.

Short-term measurement with electronic instrument is not recommended. This method can be performed if time is short or as a quick radon mitigation effectiveness check. If you measure over a short time, you will receive an indication if the levels are too high or low. Indicative short-term measuring is processed at lightening speed. You must measure over at least 7 days, and the measuring operation can be performed throughout the year. You will receive the results within a few days. This method can be performed if time is short or as a quick radon mitigation effectiveness check. If you measure over a short time, you will receive an indication if the levels are too high or low.