Reload Index (ZRiChK UMCS)

 

 

CONTAMINATION WITH 222Rn OF SOME DWELLINGS IN THE OLD TOWNS OF CHEŁM AND ZAMOŚĆ

 

ST. CHIBOWSKI, A. KOMOSA, U. WŁADZIŃSKA, M. KORNAFEL

DEPT. OF RADIOCHEMISTRY AND COLLOID CHEMISTRY

 

            The 222Rn is an alpha-emitting gaseous isotope which is formed by decay of 226Ra. Radon decays producing the short-leaving alpha emitters in a form of charged particles. These products are responsible for about a half of total dose, which Polish inhabitants receive from the natural sources (about 1.3 mSv/year in 1997 [1]).

            Radon as a heavy gas cumulates in building basements. There is no possibility to predict a value of concentration of radon in dwellings. For this reason the measurements are necessary. Determination of radon concentration in selected buildings of the Old Towns of Chełm and Zamość were performed using a passive method and alpha spectrometric method. The results are presented in Table 1.   Observed values differ in a large extent and in a few places reach a very high level, exceeding many times a dose limit (which is set on value of 200 Bq/m3 in dwellings). Because a frequency distribution of the results is usually a log-normal one, a geometric mean, which describes better the average value, was calculated.

 

Table 1. The results of 222Rn concentration measurements in Chełm and Zamość Old Towns.

 

 

Localization

No. of sampling places

 

222Rn concentration [Bq/m3]

 

 

min.

max.

arith. mean

geom. mean

Chełm, chalk undergrounds

8

2.5

620

165

34

Chełm, basements

22

LLD

5150

660

62

Chełm, 1st floors

12

LLD

48

16

11

Zamość, basements

36

0.3

608

63

5

 

References:

[1]. Ochrona Środowiska 1998, GUS, Warszawa 1998.

 

Grant KBN 3T09C·034·15