Direct Ion Dosimetry

[atomicarcheologist]

I am wondering if anyone has any experience with the Direct Ion Storage Dosimetry that is available. i am most concerned with the Instadose,  by Quantum Products as I am on a site where it is being considered for use.   However, any opinions, comments, and responses will be graciously considered for any of these instruments.

[sandyfl]

I'd be happy to address whatever concersn you may have with the Direct Ion Storage technology. This is one of our products at Mirion Technologies, Dosimetry Services Division (Global Dosimetry Solutions).This is not a new technology, and has been in use at CERN in Switzerland for quite some time now, as well as at NPP in Europe.The device is NVLAP accredited in all photon Categories, including Accident as well as Protection ranges. It has also passed Performance Tseting in the UK through the Health and Safety Executive.

The device has been demonstrated at HPS as well as medical symposiums and conferences.

I'd be happy to discuss with anyone who has questions or interest in this technology.

Sandy Perle
(949) 296-2306 or E-Mail me at sperle@mirion.com

[Already Gone]

I have been curious about these for some time now.  Would you be so kind as to clue in us old-timers?  What is the basic theory of this dosimeter?  I, for one, was raised on the TLD.  If you could relate the two for us and perhaps highlight some advantages, I'd really love it.  Please stay in the shallow end of the theory pool if you could.

[sandyfl]

DIS stands for Direct Ion Storage

- Ion chamber and analog memory element
- Gamma and X-ray interactions with chamber wall generate secondary electrons
- Secondary electrons ionize gas in the chamber
- Ions are separated by the potential difference between electrode and wall
- Ions are stored into memory element cell
- Stored charge controls memory element
- MOSFET element
- Gamma and X-ray reactions with silicon oxide
- Electrons drifting to surface states
- Responds to pulsed radiation
- Accredited NVLAP Categories I, II and IV General Categories
- 1 mrem to 500 rads

Instadose uses the same technology as the DIS-1 dosimeter:

Instadose allows users to have the flexibility to view their radiation dose at any time from any computer with internet access. Readings via a PC are enabled by a USB compatible detector.

When a user wishes to obtain a reading they simply log-in to their account, plug-in instadose to a USB port and log in to their. The accumulated dose stored on instadose is processed through a proprietary algorithm. Once complete a graphical representation of the current dose will load on the screen. Users can also view their cumulative dose level by clicking "View Cumulative Dose."

I have a Power Point presentation if anyone is interested.

[sandyfl]

The Instadose website with other information can be found at:

http://www.instadose.com

Will be happy to answer all questions. I travel frequently, but always respond almost immediately when I have a signal, no matter what time zone I happen to be in!   

[sandyfl]

Interesting comparison TLD, Film and DIS, provided by Health Canada

http://www.hc-sc.gc.ca/ewh-semt/pubs/occup-travail/technology-technologies/index-eng.php

[Already Gone]

Thanks.  It looks like a cool device.  How does it stand up to abuse?  For example, what would be the effect of dropping it 10 - 20 feet onto a hard surface?  Would the reading still be the same?

[sandyfl]

Should be, but I don't have any data at the moment specifically for this height. The device is intended to meet the requirements of IEC 61066

5.1. Drop test
Requirement: A dosimeter shall be able to withstand drops from a height of 1.5 m onto a hard
wood surface without the additional indication exceeding 0.7 HLOW. These tests shall be on each
face of the dosimeter.

The DIS-1 passed this. Since the Instadose detector is sealed and is on a small electronic board, there isn't much that could be moved or dislodged during a drop. Very compact. No power source other than a very small battery to maintain power to the memory, maintaining assignment and cumulative dose, etc.

[atomicarcheologist]

Thanks to snadyfl for the information, and I am not interested in shutting of the discussion.  However, I was wondering if any of the 200 plus readers of this thread would please fill out the poll?   I am interested in the usage of this dosimetry in the industry and in what area of the industry it is being used.  Thanks.

[Laundry Man]

I have been curious about these for some time now.  Would you be so kind as to clue in us old-timers?  What is the basic theory of this dosimeter?  I, for one, was raised on the TLD.  If you could relate the two for us and perhaps highlight some advantages, I'd really love it.  Please stay in the shallow end of the theory pool if you could.

Court, I was raised on film badges.
LM

[Motown homey]

Thanks to snadyfl for the information, and I am not interested in shutting of the discussion.  However, I was wondering if any of the 200 plus readers of this thread would please fill out the poll?   I am interested in the usage of this dosimetry in the industry and in what area of the industry it is being used.  Thanks.

The poll doesn't make much sense to me.  If you're asking where we work, get rid of the No and the Yes/no.  If you're asking if we use direct ion dosimetry, Yes and No (or Use and Don't Use) are all that's needed.  If you're asking us where we work and if we use these, make a Use and a Don't use option for each of the site classifications.

Just trying to help.

[atomicarcheologist]

Thanks for your input, Motown homey.  It appears as though a Moderator read you suggestion and beat me to the alteration.  I appreciate the help and steerage for this thread.
Live long and prosper.

[SloGlo]

When a user wishes to obtain a reading they simply log-in to their account, plug-in instadose to a USB port and log in to their. The accumulated dose stored on instadose is processed through a proprietary algorithm. Once complete a graphical representation of the current dose will load on the screen. Users can also view their cumulative dose level by clicking "View Cumulative Dose."

sounds like a pretty good instrument.
what level of durability is to be expected?
is the housing contamination resistant or at least easily deconable?
would you expect newbies with this type of dosimeter to be downloading their dose more frequently when first issued it and having the unit checked less frequently as time goes on?
has there been any "rem racing" noted between users?

[atomicarcheologist]

No users of this dosimetry?

[sandyfl]

The Direct Ion Storage technology has been primarily used in Europe, specifically the DIS-1 (CERN, NPP and Medical Institutions). The Military DIS is being used by some European NATO entities.

Is is not surprising that in the USA this technology has not been in use, since until the Instadose product was developed and launched in May 2009 (not even a year ago), it is now accredited through NVLAP, thus allowing it to be used in the US for "dose of record". As I mentioned previously, this particular device version was intended solely for the medical market, photons (15 keV up to 1.33 MeV). Since its introduction, it is being used for specific activities in university, large medical facilities and some nuclear plants have purchased, again for specific functions (such as visitor, emergency kits, etc.). The current device is being used and tested at various National Labs as well as some of the US military facilities.

As a result, the survey only validates what has been the case, with a device just entering the US geographical area, with an accreditation.

I could also state the same being true for other technologies, such as RPL (radio photoluminescence), not in use at all in the US, but is Asia and in various parts of Europe. Lack of knowledge or familiarity can not be correlated to quality or ability to monitor. Mirion's goal is to bring new technologies to the world of dosimetry, and Instadose is the first of many new devices that will be brought for consideration.

[atomicarcheologist]

Thanks for your input sandyfl.  I didn't realize it was only recently accredited by the NVLAP.  Could you offer some breakdown of the European user market?

[sandyfl]

The Direct Ion Storage technology, primarily through the DIS-1 model, links provided above, is currently in use at CERN, first approved electronic personal dosimeter in Sweden at the County Councils in Östergötland and Kalmar (http://www.springerlink.com/content/h64u657141760ng0/), and other locations (don't have links).

Additional data and links:
Radiation Technology Office, Naval Surface Warfare Center, Carderock Division (http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TJN-442C8N2-1W&_user=10&_coverDate=09%2F30%2F2001&_rdoc=1&_fmt=high&_orig=search&_sort=d&_docanchor=&view=c&_searchStrId=1198407103&_rerunOrigin=google&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=ab4e9768f5740def725541a9da6ec526), Switzerland Medical Centre (http://rpd.oxfordjournals.org/content/96/1-3/255.abstract), Japan Heavy Charged Particles (http://www.jstor.org/pss/3580448), Austria Nuclear Research Centre (http://rpd.oxfordjournals.org/content/early/2007/06/11/rpd.ncm240.full.pdf)

A Google on DIS, Direct Ion Storage, etc., will find a wealth of information.

Thanks,

[atomicarcheologist]

sandyfl,
Thanks for all your input!  I'm still looking for the demographics on use and haven't found a breakdown on any of the Internet searches that I've done.  I will chase those that you have listed.  Thanks again for your assistance.