Principal Authorized Users (PAU) are required, as a condition of their authorization, to perform weekly surveys. Surveys are used to identify and quantify radioactive contamination and radiation levels. This guide is provided to assist you in performing surveys and documenting routine weekly surveys.
Surveys are required to be performed by the Principal Authorized User in all labs under a permit that allows use of radioactive material. This includes common equipment areas where several labs are using radioactive material. One Principal Authorized User is generally responsible for ensuring that the area is surveyed on a weekly basis.
Please feel free to contact the Radiation Safety office with any questions regarding laboratory surveys or other radioactive material use issues.
Radiation Safety Office
Health Sciences Campus
Environmental Health & Safety Building
CI-1002
706-721-9826
706-721-9844
Radiation Safety Tech:
706-664-8607
Campus Emergency:
706-721-2911
There are three (3) categories of surveys that are performed in a lab:
1. Fixed contamination surveys
Used to locate radioactive material that can not be removed by applying moderate pressure. Fixed contamination is quantified by :
Good radiological practice is to make sure that the SER is kept below twice the ambient background.
2. Removable contamination surveys
Used to locate radioactive material than can be removed by applying moderate pressure. Removable contamination presents a personnel hazard and also an internal hazard due to the possibility of ingestion. Removable contamination is defined in units of:
Contaminated areas generally have removable contamination, but may have a combination of the two types.
3. Ambient dose-rate surveys
Measures the amount of ionization in air, taken 30 cm from the source of radiation.
The key to an effective contamination survey is to use the proper instrument.*
Geiger Mueller (GM) Survey Meters and NaI Scintillation Survey Meters: For detecting a surface emission or exposure rate, Augusta University Research facilities uses these two common portable survey meters.
Wipe Tests: Must be used to survey an area for H-3 contamination. Due to their high efficiency, wipe test counters, such as liquid scintillation counters and gamma counters are very effective tools for identifying removable contamination. Gamma counters are used for counting wipe tests for photon emitters, such as: I-125, I-131, Tc-99m, or Cr-51.
Liquid Scintillation Counter: The best instrument for detecting removable beta contamination. Its efficiency is high for a wide range of b-emitting nuclides. It is the best choice for removable contamination surveys in radioactive material laboratories not working with pure photon emitters such as those mentioned above.
*If you are unsure of the correct counting instrument to utilize, contact the Radiation Safety Office.
Check Radiation Safety Office instrument calibration label. Contact the Radiation Safety Office for calibration if calibration is greater than one year old.
Check batteries.
Turn on audio circuit.
Perform operational check. Expose meter to attached check source to verify that the instrument is operating.
Determine background reading by holding the meter over an area that is not contaminated.
Record on the survey form the date of the survey and indicate the instrument used and the required instrument information.
Routine Contamination Surveys are required to be performed weekly when radioactive material is used. A good working practice is to perform a survey following each experiment involving radioactive material. If your laboratory uses radioactive material infrequently, you may suspend routine contamination surveys as long as you document the non-use.
A record of the survey performed after the last use must be on file, however, it is a requirement of the Augusta University Radiation Safety Guide that non-use of isotopes be documented if no survey was performed for the week. For your convenience, there is a column on the survey form to easily document non-use of isotopes for the week.
Survey Locations
Survey locations should be chosen to reflect both areas where there is a likelihood of detecting contamination and also for which contamination might be accidentally spread.
Some suggested locations:
Doorknobs and the floor at entrances to the lab
Utilizing the provided laboratory survey form, indicate the survey locations with numbers corresponding to the locations.
To perform this survey:
Fixed contamination surveys do not have to be documented, but are an extremely good radiological practice. These surveys will help you locate possible contamination that can be quantified with a removable contamination survey.
To perform this survey:
Record counting results, identified contamination, subsequent actions, and resurvey results.
Any location in which the count rate is more than 200 dpm/100cm2 should be considered contaminated.
Resurvey the area to verify that the contamination has been removed. If the contamination appears to be fixed, mark the area and notify the radiation safety office for assistance. If high level contamination is discovered and assistance in decontaminating the area is required, contact the Radiation Safety Office.
To perform this survey:
