| 摘要 |
PURPOSE:To enable measurement of pollution accurately and quickly in the environmental atmosphere, by performing additional measurement during the collection of dust and before the blank measurement within one cycle of measuring time after the end of the measurement of a filter paper following the dust collection. CONSTITUTION:A trapping section 10 is provided with an air supply pipe 12 in such a manner as to communicate therewith. A rollable filter paper 14 is introduced 16 into the trapping section 10 to trap 14 floating dust contained in air passing through the trapping section 10 and it 14 is sent with a winding reel 18 to a specified position to measure the filter paper 14. Furthermore, the measurement of transmission beta dose through the filter paper 14 is made by a detector section 20 comprising a beta ray source and a detector for measuring beta rays. Transmission beta dose only through the filter paper 14 as measured at a blank position B is inputted into a memory 24 through a controller 22. Transmission beta dose after the collection of dust as measured at a major measuring position M is inputted into a density computing circuit 26 through the controller 22 to calculate the ratio with a blank measured value outputted from the memory 24 and the density of floating dust is computed and recorded 28. In this manner, the pollution in the atmosphere can be measured quickly. |
