Skip Ribbon Commands
Skip to main content





| |

​How does one get an online dose report? (May 7th, 2012)

Answer Collapse/Expand Text:

​DATE:  May 7, 2012
TO:  SLAC Personnel with GERT and/or RWT
FROM:  Environment, Safety and Health
SUBJECT:  New Online Dose Reports Replace Paper Reports from the SLAC Dosimetry Office

As SLAC personnel with General Employee Radiological Training (GERT) and/or Radiological Worker Training (RWT), you use a dosimeter to monitor your radiation exposure from SLAC operations. You can now have instant access to your lifetime occupational dose exposure through SLAC's Occupational Dose Tracking System (ODTS) <> . Simply log in to the system and select the "My SLAC Dose Report" tab in the upper right-hand corner of the page.

Please note this online report replaces the paper reports that have been sent each year from the SLAC Dosimetry Office to employees with GERT and/or RWT.

Your dose report is confidential, so a valid SLAC Windows user ID and password are required to access the ODTS. Managers also have access to dose reports of all personnel working under their supervision.

If you do not have a SLAC Windows account or you want more information, please contact Santa Chatterji <>  in the Radiation Protection Department at ext. 3879 or read the Frequently Asked Questions <> .

​Where can I find radiation survey maps?

Answer Collapse/Expand Text:​

​What do I do with my dosimeter when I leave?

Answer Collapse/Expand Text:

Either hand it to Christine or put it in the dosimeter drop box in her cubicle. There is also a dosimeter drop box in NLCTA.

Remember to put your name on your dosimeter if it isn't printed on it.

​How much dose is seen in FACET tunnel and how can I shield equipment from the radiation?

Answer Collapse/Expand Text:
There were studies into the radiation dose and shielding methods in FACET in May 2012.
Dose readings from approximately a week of beam running show doses of between 1.7 and 3.75 kilorad depending on location on the experiment tables.
Shielding results:
1/2 inch Pb typically provides shielding factors between x 3.5 and x 7.
2" Pb, has a shielding factor between x 11 and x 57. 
4" Pb shielding improves on the 2" shielding somewhere between x 4 and x 8.
6" Pb shielding essentially provides no additional benefit.
Thanks to Clive Field, Henry Tran and Santa Chatterji. 




​Why does my dose report read zero when I know I got more?

Answer Collapse/Expand Text:

Due to issues with sensitivity and background uncertainties, any dose below 10 mrem is recorded as zero.

If your personal dosimetry tracking indicates that you should have more than 10 mrem but this is not reflected in your dosimeter reading, get in touch with the FACET User Manager in case there has been some error. However, the personal dosimeters we use (RADOS) are used as an indicator only and the film dosimeters are the ones that give the reading me trust and use in official records. Small discrepancies are to be expected.

​I'm pregnant or am trying to become pregnant- do I have to tell anyone?

Answer Collapse/Expand Text:
You are not required to declare that you are pregnant but if you wish to, there is a form.
This is totally voluntary.  
If you are pregnant, you have the option to declare your pregnancy and/or request reassignment. Workers who have declared pregnancy must meet additional dosimetry requirements.


The embryo-fetus is known to be more sensitive to radiation than adults due to the rapid division rate of
developing cells. Radiation doses can increase the chances that the child will experience slower growth or
mental development, or develop childhood cancer.


​I've had medical treatment with radioisotopes - does this matter for dosimetry?

Answer Collapse/Expand Text:

​If you actually wear your dosimeter during the treatment, this does matter and the dosimeter needs to be turned in and the treatment reported (ask at the badging office for the damaged dosimeter form).

If you have had treatment and are coming to SLAC to work, please let us know if the treatment is within the past 3 days.

Most nuclear medicine diagnostic procedures are using short half-life (few hours) isotopes (eg. Tc-99m, F-18, etc..) so it is safe to wear dosimeter after 3 days (i.e. there won't be a false positive reading on your dosimeter).
During this ~3 day period in which the isotopes are decaying, we may have to ask that you do not perform any radiological work or enter RCAs because we cannot accurately monitor your occupational dose.

SLAC SLAC National Accelerator Laboratory, Menlo Park, CA
Operated by Stanford University for the U.S. Dept. of Energy