Ionization chamber method radon

Ionization Chamber Method (DSC), The ionization chamber is one of the most common instruments for measuring radon gas. The chmaber was cylindrically shaped and had a 1.5 liter volume. Air samples were drawn through a dryer filled with CaCl and a filter to remove... 

Flow-Type Ionization Chamber (PFC). The Flow -Type Ionization Chamber Method (PFC) has been developed for continuously measuring radon gas in the atmospheric air. The detail of the device has been described elsewhere (Shimo, 1985). Briefly, measurements are continuously carried out by drawing air through the detector at 1.0 2.0 /min. The ionization currentdue to alpha particles from radon and its daughters is detected with a vibrating reed electrometer (VRE) in the same manner as the DSC. The sensitivity... 

The instruments include an ionization chamber, the charcoal-trap technique, a flow-type ionization chamber (pulse-counting technique), a two-filter method, an electrostatic collection method and a passive integrating radon monitor. All instruments except for the passive radon monitor have been calibrated independently. Measurements were performed... 

In the following year Miles. Curie and C. Chamie measured the half-life period of radon by a method which is very simple in principle. If a single tube of radon placed in the ionization chamber yields at time t a... 

The apparatus is best calibrated using a radium solution, the activity of which is of the order of magnitude of approximately 10 nCi. The radon -which is in equilibrium - is transferred from the radium solution to the ionization chamber by means of a suitable de-emanation method... 

Suitable methods of transferring the radon 222 into the ionization chamber... 

In this latter method air is introduced to an ionization chamber after being filtered to remove airborne radon progenies. The current in the chamber is proportional to the radon concentration. The lower detection limit depends on the volume of the ionization chamber and can be as low as 0.5 Bqm . Ionization chambers are very complex laboratory instruments typically used as reference standards for their accuracy. In some laboratories, the ionization chambers are used as a standard for calibrating other instruments. 

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