Monthly Archives: June 2014

Medical Geology Post on Environmental Radon

General radon levels in the environment can vary greatly, depending on locale and the medium it is measured in. Here are comparisons between indoor/outdoor air, soil air and groundwater.

Again, the conversion factors are from the picoCurie/liter to the Becquerel / m^3:

1 picoCurie / liter = ~ 37.1 Bq/m^3     EPA action limit 4 pCi/L = ~ 148.4 Bq/m^3

 

Radon:  Outdoor air      Low of 4 – 8 Bq / m^3    =  0.2 – 0.3 picoCuries/liter

High of 100 Bq / m^3 in valleys (morning time)  = 2.7 picoCuries / liter

Radon:  Indoor air  Low  20 Bq / ^3  = 0.5 pCi/l

High of 110000 Bq / m^3  = 2964 pCi/l  (probably over a uranium mine)

 

World average  39 Bq / m^3   = 1.1 pCi/l

 

EXAMPLE INDOOR RADON LEVELS by Country: Average

Egypt:   9 = 0.2 pCi/l

UK:  20 =  0.5 pCi/l

USA:  46 = 1.5 pCi/l     Texas  48 = 1.3 pCi/l

United States by Region:  (geometric mean values)  3.43 pCi/L in the Northeast   2.36 pCi/L in Midwest, 0.64 in the Northwest, 2.40 pCi/L in the Mountain States, 1.43 pCi/L in the Southeast

Sweden:  108   = 2.9 pCi/l

Czech Republic: 108 = 2.9 pCi/l

Highest ever radon concentration ever reported in an indoor dwelling:   2600 pCi/L in a southeastern Pennsylvania home which is equal to a 4 pack a day smoker.

Radon in soil air:   Ranges from less than 1 to over 2500 Bq / liter  = 0.03 – 67.4 pCi/l

Most soils in the USA are between 5 – 55  Bq/liter  = 0.13 – 1.48 pCi/l

Radon in groundwater:  3 – 80000 Bq/liter  = 0.081 – 2156 pCi/l