Trade.Information

Product Name: Plutonium and Uranium in Soil

Product Description

System: Electret Ion Chamber 
Lab/Field: Field (In situ measurement on soils) 
Radiation detected: Alpha 

Operation 

This system is a passive integrating detector for measurement of alpha-emitting contaminants in soils. It consists of a charged Teflon disk(electret), open faced ionization chamber, and electret voltage reader and data logger. When the electret is screwed into the chamber, a static electrostatic field is established and a passive ionization chamber is formed. The chamber is deployed directly on the surface to be measured. Alpha particles emitted from the contaminated soil enter the chamber, ionize the air molecules, the ions are attracted to the charged surface of the electret, and the electret charge originally present gets reduced. The electret charge is measured before and after the exposure with a portable electret voltage reader, and the rate of change of the charge ( change divided by the time of exposure) is proportional to the alpha activity of the soil. Electret ion chambers(electret +chamber) are inexpensive, simple, passive, with no moving parts or electronic components, unaffected by ambient environmental conditions and can be normally used for several measurements before a need for replacement of the electret. A thin Mylar window may be used to protect the electret from dust. In low-level measurements, a second detector with a Tyvek filter may be deployed in parallel to correct for background response.

Specificity/Sensitivity: 

This method is for gross alpha radiation measurement. The measurement may be converted to elemental or isotopic concentration ( such as Pu, U or Ra) if the isotopes are known or measured by another method. The lower limit of detection is a function of deployment time: 64 pCi/g, 22pCi/g, 9.3pCi/g with deployment times of 1 hour, 8 hours, 48 hours respectively. 
Applicability for Site Clean up: 

Highly contaminated soil may be measured with a deployment times of a few minutes. Surface alpha activity down to background levels may be quantified with deployment times of 48 hours or more. Several hundreds of detectors can be deployed and analyzed at a time using one measuring/analyzing instrument. 
Cost
Cost of Equipment: $ 4000 to $ 10000 
Consumable cost of detector per measurement: Under $ 1

Company Details

Rad Elec Inc (REI) was incorporated in 1987 to manufacture and commercialize a product researched and developed under a research contract with NYSERDA (New York Energy Research and Development Authority) during 1986 -1987. The product was based on... more