| 摘要 |
<p>A method of measuring radioactive radiation originating from the ground over a specific plot of land or building utilises two or more detectors (2,3) spaced at a distance (A) apart and at an equal height (H) above ground level; the readings from these detectors pass to a calculating unit (4) and are indicated at a display unit (5) as the difference between the two levels of radiation intensity (6,7) at the relevant locations. Two detectors are pref. used, and the data obtd. is fed cyclically and alternately to a central reception unit (10). The calculator (4) is pref. a computer. This may be programmed to indicate which of the two detectors is obtg. the highest reading. For obtg. readings of natural ground radiation and plotting the results as intensity profiles, more specifically in the manner of a relief map. The method and appts. enable the readings to be very rapidly taken and evaluated. The method can be used for extremely localised measurements for example in buildings occupied by humans and animals.</p> |
