[ RadSafe ] Beta correction calculation

[Smith, Lawrence E]

The beta correction factor for the ion chambers that I use was determined years (decades?) ago using a slab of depleted uranium. The beta dose rate at a certain distance (I believe 2.5 cm) is a known level. The meter is then positioned on the slab for the closed window and the open window readings. The beta correction factor can then be determined. 

For standard calibration of an ion chamber with a one point adjustment, calibration at the mid-scale reading (25 mr/hr on a 0 - 50 mr/hr scale) should show readings that are within 10% of the readings for the 20% and 80% readings.

Larry Smith

Today's Topics:

   1. Re: rad monitor calibration (Dennis Quinn)

-----Original Message-----
From: radsafe-bounces at health.phys.iit.edu
[mailto:radsafe-bounces at health.phys.iit.edu] On Behalf Of Brent Rogers
Sent: Sunday, June 01, 2014 8:04 AM
To: ROY HERREN; The International Radiation Protection (Health Physics) Mailing List
Subject: Re: [ RadSafe ] rad monitor calibration

On a similar vein, does anyone know for certain how the beta-factor on ion chambers is determined?  I'm speaking of obtaining beta dose rates using (open window - closed window) * beta factor.

Regards
Brent Rogers
Sydney Australia

Sent from my iPad

> On 1 Jun 2014, at 3:55 pm, ROY HERREN <royherren2005 at yahoo.com> wrote:
> 
> 
> The calibration procedures will vary depending on which specific
instrument your calibrating.  Unless you have the in-house expertise, I highly suggest that you leave the instrument calibration to the instrument vendor.  In any case, your instrument vendor should have provided you with an instrument manual when you purchased each of the instruments.  Look through the instrument manual to see if it lists any information about instrument calibration.  Do you own an instrument calibration source?  If so, also look up what the literature from calibration source manufacturer/vendor provides regarding instrument calibration. 
> 
>  
> Roy Herren
> 
> 
> On , ROY HERREN <royherren2005 at yahoo.com> wrote:
> 
> 
> 
> 
> Are you specifically referring to the Rad MonitorTM instruments
manufactured by Lab Logic, see Rad-Monitors
> 
> 
>   Rad-Monitors
> View on www.lablogic.com Preview by Yahoo
>  
>  
> Roy Herren
> 
> 
> On Friday, May 30, 2014 1:18 PM, "JOHN.RICH at sargentlundy.com"
<JOHN.RICH at sargentlundy.com> wrote:
> 
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End of RadSafe Digest, Vol 1603, Issue 1
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