Glossary of terms

 Bequerel (Bq)        EPERM       Environmental Radiation        

Mitigation         picoCurie and pCi/L       Radon    

Radiation dose          Radon Progeny      Radiation Risks

         RAD, REM, Gray(Gy), Sievert (Sv)          Retrospective        Thoron

 

Bequerel (Bq) and Bq/m3
Bequerel is the international standard unit for radioactivity; that is the rate that radioactive materials decay. One Bq is one decay per second. The US unit of radioactivity is the Curie(Ci). One Ci is 3.7x 1010 decays per second. Bq/m3 is the international unit for volumetric activity concentration. The relationship between activity concentrations is that 1 pCi/L = 37 Bq/m3  
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Dose units: RAD, REM, Gray(Gy), Sievert (Sv) ect.
There are some thorny details that I will omit in this definition to give you the basic idea: Dose is a measure of energy absorbed in matter. The basic units are RAD (US) and Gray (international). 1 Gy=100 RAD. Dose Equivalent includes the energy deposited and the effectiveness of that dose at producing damage in biological cells. The basic units are REM (US) and Sv (international). 1 Sv=100 REM.   Effective Dose Equivalent includes the sensitivity of the human organ to the Dose Equivalent. It is a new concept and is only given in units of Sv.  Top

 

Environmental radiation                                                                                                                                                              Environmental radiation is energy created by the decay of naturally-occurring radioactive elements like uranium, thorium, and potassium.  These elements are found in the soil, air, water, building materials, and food. Top

 

Mitigation
Mitigation is the process of reducing radon gas related exposure in the home or workplace. It usually involves a change in the building's structure or systems. Often it requires a new device or system to achieve the desired level of reduction.  Common mitigation techniques include increasing indoor ventilation (open windows, air-to-air heat exchangers), removing radon progeny from the air (filters, fans), or ventilating the soil surrounding the building. Top

 

picoCurie and pCi/L
The US unit of radioactivity is the Curie(Ci). One Ci is 3.7x 1010 decays per second. One picoCurie is 3.7x 10-2decays per second or 3.7x 10-2Bq.  pCi/L is the US unit for volumetric activity concentration. The relationship between activity concentrations is that 1 pCi/L = 37 Bq/m3  Top

 

Radiation dose                                                                                                                                                                                             Radiation dose is the effective energy absorbed by human tissue when struck by radiation. The risk of developing a cancer is proportional to dose, at least for doses above a “yet to be determined” threshold. Top

 

Radiation Risks                                                                                                                                                            Radiation risks are an increased chance of developing a cancer when exposed to high doses of environmental or anthropogenic radiation. Top

 

Radon
A nickname for the isotope 222Rn of the element Radon. 222Rn has a 3.8 day half-life, the longest of any Radon isotope. It is a noble gas generated by the decay of radium found in rocks and derived materials. It decays via alpha and beta emission through a series of short-lived progeny, 218Po,214Pb,214Bi, 214Po to a moderately long-lived (21 years) isotope of lead; 210Pb. 210Po is radon's last mortal daughter. She decays into 206PbTop 

 

Radon progeny/decay products/daughters
The series of nuclei that are produced when radon decays
Nucleus: 222Rn > 218Po>214Pb>214Bi> 214Po> 210Pb>210Bi> 210Po > 206Pb
Emits:                
a       a           b         b        a          b         b        a
Life:                   4d       3 min     27 min   20 min   <1ms    21y      5d         138d    stable                                                                                             Top

 

Retrospective                                                                                                                              Retrospective means looking to the past. Radon leaves a residue in glass surfaces that can be used to estimate the average radon concentration over past decades. Top

 

Thoron
A nickname for the isotope 220Rn of the element Radon. 220Rn has a 55 second  half-life, much shorter than 222Rn. It is a noble gas generated by the decay of radium found in rocks and derived materials. It decays via alpha and beta emission through a series of short-lived progeny. It is not as common as radon in the environment. Indoors it is thought to contribute about 10% of the total airborne radiation dose.  Top

 


More to come....let me know if there are terms you would like to see defined.


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