宁夏回族自治区环境天然贯穿辐射水平调查研究

INVESTIGATON OF ENVIRONMENTAL NATUKAL PENETRATING RADIATION LEVEL IN THE NINGXIA HUI ANTONOMOUS REGION

本文报道了宁夏回族自治区环境天然贯穿辐射水平调查的方法和结果。全区以２５ｋｍ×２５ｋｍ的网格均匀布点，共布设网格点９５个，另外布设各类加密点１１２个。调查结果表明：（１）宁夏回族自治区原野γ辐射剂量率按面积、人口和网格点的加权均值分别为６１．０、６０．８和６０．８ｎＧｙ·ｈ￣（－１）；（２）道路γ辐射剂量率按网格点平均为５４．５ｎＧｙ·ｈ￣（－１）；（３）室内γ辐射剂量率按人口和网格点加权均值分别为１００．４和９８．２ｎＧｙ·ｈ￣（－１）；（４）宇宙射线电离成分（不包括中子成分）所致空气吸收剂量率按网格点和人口加权均值，室内分别为４１．１和３９．７ｎＧｙ·ｈ￣（－１），室外分别为４６．２和４５．２ｎＧｙ·ｈ￣（－１）；（５）天然贯穿辐射剂量率，按网格点和人口加权均值，室内分别为１３９．５和１４０．３ｎＧｙ·ｈ￣（－１），室外分别为１０７．０和１０５．９ｎＧｙ·ｈ￣（－１）；（６）天然γ辐射、宇宙射线和天然贯穿辐射所致居民人均年有效剂挝当量分别力Ｏ．５５、Ｏ．３６和０．９１ｍＳｖ；所致集体年有效剂量当量分为０．２１４、０．１４０和０．３５４×１０￣４人·Ｓｖ。

The methods and results of the investigation on natural penetrating radiation levelin the Ningxia Hui Autonomous Region are presented.95 25 km×25 km-grid measuringpoints were set uniforrnly up all over the region,with 112 densely measuring points of different types added.The results show that:(1)The area-weighted, population-weighted and point-weighted average value of natural γ radiation dose rate for field is 61.0,60.8 and 60.8nGy·h￣(-1).respectively;(2)The point-weighted average value of natural γ radiaton dose ratefor road is 54.5 nGy·h￣(-1);(3)The population-weighted and point-weighted average value ofnatural γ radiaton dose rate inside buildings is 100.4 and 98. 2 nGy·h￣(-1),respectively;(4 )the point-weighted and population-weighted average value of the dose rate inside buildingsfrom cosmic ray is 41.1 and 39.7 nGy·h￣(-1), and outside buildings is 46. 2 and 45.2nGy·h￣(-1),respectively;(5) The point-weighted and populationt-weighted average value ofnatural penetrating radiation dose rate inside building,is 139. 5 and 140. 3 nGy·h￣(-1).outsidebuildings is 107.0 and 105.9 nGy·h￣_(-1), respectively;(6) The annual effective dose equivalent from cosrnie ray,natural γ radiation and natural penetrating radiation is 0.36,0.55 ando.91 mSv,respectively;and correspondingly,the annual collective effective dose equivalent is0.140.0.214 and 0.354×10￣4man· Sv,respectively.