Radiation exposure of workers in storage areas for building materials

Peer review under responsibility of Taibah University

Figures & data

Fig. 1 Ranges and mean activity concentrations of radionuclides (Bq/kg) in the most commonly used raw building materials in all samples in eight categories.

Table 1 Geometric mean activity concentrations of radionuclides (Bq/kg) in the most commonly used raw building materials in eight categories.

Category	^232Th	^226Ra	^40K	Total activity (%)	Radioactivity index
Bricks (clay, lime, fired clay)	58.1 ± 3.1	20.4 ± 2.1	459.6 ± 116.8	13	0.54
Sands and gravels	13.30 ± 1.6	10.4 ± 0.4	352.2 ± 69.6	9	0.21
Pure cements	32.8 ± 3.9	15.2 ± 8.8	229.54 ± 174.0	7	0.35
Cement blocks	14.98 ± 1.4	11.5 ± 1.4	378.37 ± 42.0	10	0.23
Porcelains (marble, mazzaiko)	59.9 ± 25.1	31.3 ± 41.5	486.4 ± 542.5	14	0.58
Gypsum ceiling	20.59 ± 1.32	18.2 ± 1.1	293.23 ± 120.9	8	0.26
Light mud (on roofs)	20.91 ± 1.32	16.8 ± 1.5	271.16 ± 44.6	8	0.25
Surface materials	213.4 ± 30.4	76.8 ± 27.9	900.3 ± 407.5	30	1.62
Range	3–394	2.8–108.2	82–1413
Geometric mean	52.4	20.6	206.9
Standard deviation	55.2	17.6	113.6

Fig. 2 Histograms of radioactivity (²²⁶Ra, ²³²Th and ⁴⁰K) in building materials.

Fig. 3 Histogram of indoor radon concentration, showing a normal distribution.

Table 2 Descriptive statistics of radon concentrations in poorly ventilated and unventilated storage areas and shops.

Ventilation	Number	Radon concentration (Bq/m)			Standard deviation
		High	Low	Average
None	28	247 (292)	72	126	45.4
Poor	22	247	71	123	44.5

Fig. 4 Correlation between radium (²²⁶Ra) in building materials and indoor radon (²²²Rn).