The Lucas Cell

The Lucas cell is a hollow cylinder, sealed with a glass window at one end a "quick connect" at the other end. The inside is coated with silver activated zinc sulfide, or ZnS(Ag). This phosphor emits a pulse of light (photon) or scintillates when an alpha particle hits it. The cell is viewed by a photomultiplier tube and the scintillations counted by electronics. The Lucas cell is the size of a drinking cup because that is the range of an alpha particle in air -- a few inches.

Named after its inventor, Henry Lucas (1957), the Lucas cell is also known as scintillation cell or radon cell.

Radon is an alpha-emitting noble gas and readily separated from solution in water into a gas phase and passed into a Lucas cell where its radiation is counted. There are no interferences. The parent-daughter pair radium-radon grows into equilibrium in a few days and thus the Lucas cell provides a very sensitive method for the analysis of both these elements. The Lucas cell provides the basis for EPA Method 903.1 for radium in drinking water and can easily be applied to radium in food etc. as well as radon. At standards somewhat less rigorous than the EPA our system can provide quick turn-around at environmental levels. Many samples can be analysed in a work day.
coming soon:

Some tricks to speed things up and protect your Lucas cells.
We provide all the necessary equipment, including degassing system, Lucas cells, and radon counting system.

For instruments contact
R.H. Morse & Associates Ltd.
skype: robert.morse.toronto

Robert H. Morse, Ph.D., P.Eng.
Click here for technical details and other applications of our radon instruments.
Lucas, Henry F., 1957: Improved low-level alpha scintillation counter for radon, Rev. Sci. Instruments, vol 28, No. 9, pp 680-683. Credited with invention of the Lucas cell, a hollow cylinder sealed at one end with a glass window and coated on the inside with silver-activated zinc sulfide. This material emits a photon of light (scintillates) and this scintillation is detected by a photomultiplier tube and counted by an electronic apparatus. The Lucas cell is the size of a drinking cup because that is the range of an alpha particle in air.
Dyck, 1969: Radon determination apparatus for geochemical prospecting for uranium, Geol. Survey of Canada, paper 68-21. Developed a portable Lucas cell system which is the predecessor of our instrument. We have been providing battery operated radon instruments since 1972.
K.P. Eappen * , R.N. Nair, Y.S. Mayya, 2008: Simultaneous measurement of radon and thoron using Lucas scintillation cell, Radiation Measurements 43 (2008) 91 97. Developed a method for the simultaneous measurement of radon (222Rn) and thoron (220Rn) using the Lucas scintillation cell. This paper presents a mathematically rigorous version of the formula for radon and thoron which I published in 1976

Copyright 1968 - 2018, R.H. Morse & Associates Ltd., all rights reserved.