Radon radioactivity measurements in underground water: A comparison between different diagnostics techniques

Figures & data

Figure 1. The map with the underground water sampling point, Mammola, put in evidence.

Figure 2. A photo of the experimental HPGe gamma-spectrometry (a), LSC (b) and emanometry (c) setups.

Table 1. A comparison of the various diagnostics techniques used for the determination of radon in underground water for human use

Diagnostics techniques	Counting efficiency (%)	Lowest detection limit (Bq/L)	Measurement uncertainty (k = 2) (%)	Background (cpm)	Sample volume (L)	Sample treatment
HPGe gamma-spectrometry	0.83^a	0.10	4.98	0.01	1	No
LSC	420^b	1.36	1.81	31.59	0.010	Yes
Emanometry	90^c	0.37	3.97	0.10	0.250	No

^aAt 1.33 MeV peak (⁶⁰Co).

^bIncluding ²²²Rn, ²¹⁸Po, ²¹⁴Pb, ²¹⁴Bi and ²¹⁴Po.

^cIncluding ²¹⁸Po.

Table 2. The location (with GPS coordinates) of the groundwater sampling point, together with the activity concentration of ²²²Rn as measured through HPGe gamma-spectrometry, LSC and emanometry

		^222Rn activity concentration (Bq/L)
Sampling point	GPS coordinates	HPGe gamma-spectrometry	LSC	Emanometry
Mammola (Borehole)	38°21ʹ02.8ʺ N 16°10ʹ34.7ʺ E	144.75 ± 7.22	147.16 ± 2.85	147.25 ± 5.85

Table 3. The activity concentration of ²²²Rn obtained from literature for groundwaters from other parts of the world

^222Rn activity concentration (Bq/L)	Country, region	Geology
1–1,000	Spain, La Garrotxa region	Volcanic
3,043	Poland, the Sudety Mountains	Volcanic (e.g., crystalline rocks)
3,800	Finland	Soil (no detail)
1,220	Germany, east Bavaria	Granite, gneiss
17–3,856	Portugal, Nisa	Granites, sediments
5.8–36.6	UK, Northern Ireland	Sherwood Sandstone Aquifer