Personal Radiation Dosimeter
Dear radiation-monitor participant:
In order to view your radiation dose readings please go to the following link (www.myldr.com). The online program uses Internet Explorer.
Username: UTHAccount Number
You can locate the Account Number you are attached to by locating the number on the backside of the badge. For example if your account number is 0040000 then your Username is UTH40000. Remove any zeros at the beginning of the account number like in the example.
Once you are logged in you must reenter the Account Number and then enter the Serial Number.
A Blank reading means you have not submitted a badge for dose analysis this calendar year.
M means your badge dose during a monitoring period was too low to be measured or approximately 1 mrem.
The maximum annual regulatory limit for radiation workers is 5,000 mrem Deep dose (DDE), 15,000 mrem Lens dose (LDE), and 50,000 mrem Shallow dose (SDE). National Average Annual Exposure from background (non-occupational) radiation is 625 mrem (NCRP 160, 2006).
Helpful reference concerning radiation and how it interacts:
Radiation Answers is a website developed by the Health Physics Society (HPS) as a central source for information on subjects ranging from general radiation facts to radiation use in industry and medicine.
Our main goal is to maintain occupational dose As Low As Reasonably Achievable (ALARA). So if you have questions concerning your radiation exposure or you would like your dosimetry records for a particular monitoring period, please call 713-500-5840
What does the dosimeter do?
A radiation dosimeter or badge does not provide protection but detects and measures radiation that you have been exposed to. The badge will detect high-energy beta, gamma or x-ray radiation. Dosimeters cannot detect low energy beta radiation from some isotopes, including carbon-14, tritium or sulfur-35.
What types of dosimeters are there?
UTHealth uses two badges for most employees, Luxel by Landauer (aluminum oxide dosimeter) and TLDs (thermoluminescent dosimeter). The Luxel badge measures whole body dose from x-radiation, gamma radiation and beta radiation. The TLD measures extremity dose (finger, hands etc.) from x-radiation, gamma radiation and high energy beta radiation. The TLD chip is housed in a plastic ring to be worn on your dominant hand. For more details on the proper procedure for wearing dosimetry see the section labeled "How do I wear my dosimeter?"
(Picture courtesy of Landauer)
Who needs a dosimeter?
Radiation workers who operate x-ray machines, flouroscopy units, certain unsealed and sealed radioisotopes or are exposed to other sources of gamma or high energy beta radiation are generally required to wear one or more dosimeters.
The following table provides general badging guidelines for those who handle radiation sources or equipment. If you meet the following criteria and do not have a badge, please contact the Radiation Safety Office at 713-500-5840.
Dosimetry Requirements UTH
No badge is required if you use:
- 3 H, 14 C, 33 P, 35 S, 125 I
A Badge is required if you use or work with:
- 32 P or 36 Cl > 10 mCi per protocol
- 86 Rb, 22 Na, 51 Cr, 131 I >5 mCi per protocol
- X-ray or Fluoroscopy
- PET Imaging / Cyclotron Facility
- Environmental Health and Safety
How do I get a dosimeter?
New personnel working with radiation sources or radiation producing devices must complete and RS-3 Form for Dosimetry during the Basic Radiation Safety training class . Once Radiation Safety reviews the form, a dosimeter will be issued if needed.
Do I need a dosimeter if I am pregnant?
Current occupational radiation control rules impose a special dose limit specifically for the unborn child (embryo/fetus) of any radiation worker who formally declares her pregnancy. This dose limit is 500 mR during the entire pregnancy. Normally the dose limit for a non-pregnant radiation worker is 5000 mrem per year. A pregnant radiation worker is not required to declare her pregnancy. However, in order for the Radiation Safety Program implement any control measures or dosimetry for monitoring, the pregnancy must be declared in writing to the Radiation Safety Program. Dosimetry is not always necessary for a pregnant radiation worker. If you have any questions or comments, please don't hesitate to contact our office at 713-500-5840.
How do I wear my ring dosimeter?
The ring badge should be worn on a finger with the label (white plate) facing the radiation source, i.e. toward the palm of the hand where the highest exposure occurs. Protect the ring badge from contamination by wearing it inside a glove. Check the badge as part of your routine survey for personal contamination. Ring badges are available in small, medium and large sizes; if your ring doesn't fit, please let us know.
When your ring badge is not being worn, keep it in a location protected from radiation and heat.
( Picture courtesy of Landauer)
How do I wear my whole body dosimeter?
Radiation workers who are issued whole body badges should wear them on their collar, mid-torso or waist with the label facing out. The intent is to wear the badge is the area most likely to receive exposure.
When your whole body badge is not being worn, keep it in a location protected from radiation and heat.
When do I return my dosimeter?
Dosimeters are issued for two categories, monthly and quarterly. The wear dates are printed on the front of the badge, under your name, as a reminder of when to wear them. Once the wear period ends, please remove the badge, keep the grey holder, and return the badge to Radiation Safety. If you are expecting dosimeters and you do not receive by the third working day of the month, please call the Radiation Safety Program for further details.
At the end of the month or quarter, dosimeters must be returned to Radiation Safety as promptly as possible to expedite the processing. All badges are processed according to the National Voluntary Laboratory Accreditation Program accrediting agency.
What do the results of the dosimeter mean?
The primary occupational whole body dose limit is 5,000 millirems per year, effective dose equivalent. The dose limit to the extremities (hands, fingers etc.) is 50,000 millirems per year.
How do I terminate a dosimeter?
When a Radiation worker leaves the University or changes work locations, please notify the Radiation Safety Program to update the records.