Radiation Safety Training Lab Survey Program Washington State University Radiation Safety Office
Lab Survey Program Why do we need to do lab surveys? Why do we need to do lab surveys?
Lab Survey Program Lab surveys are performed to check for radioactive materials contamination.
Lab Survey Program There are two types of surveys that need to be performed. First is the meter survey. And second is the swipe survey.
RADIATION MONITORING & SURVEILLANCE The meter survey Portable Survey Meters The Purpose of meter surveys is to, Assess radiation fields (mR/hr), using a dose rate meter. and/or Assess surface contamination (cpm) of radioactive materials, using a G.M. or NaI detector.
RADIATION MONITORING & SURVEILLANCE Portable Survey Meters The primary Types of Portable Survey Meters Used on Campus G.M. meters – for Beta/gamma radiation Thin window GM – Excellent for Low Energy Betas (except H-3) – Good for High energy betas – Poor for Gammas (low efficiency) Thick window GM – Good for High energy betas – Good for Gammas – Poor for Low energy betas G.M. Pancake probe.
RADIATION MONITORING & SURVEILLANCE Portable Survey Meters The primary Types of Portable Survey Meters Used on Campus, cont. NaI Thin Crystal Detectors – Excellent for Low Energy X & Gamma radiation – Poor for High energy gammas – Poor for betas G. M meters and NaI detectors are not good for Neutron Radiation. It is very important to have the proper meter for the isotopes in your laboratory.
RADIATION MONITORING & SURVEILLANCE Other Survey Meters used for special purposes Dose rate meters – For Radiation Fields Alpha Meters Neutron Meters
Survey meter use. 1) Before using your meter, first check the calibration sticker. Most meters are calibrated once a year. Be sure your meter is in calibration. If it is not, do not use it and contact the Radiation Safety Office.
Survey meter use. 2) Perform a battery check. This is performed differently on different meters. So please become familiar with your meter.
Survey meter use. 3) Check the background radiation levels. Remember there is always background radiation.
Survey meter use. 4) Check your meters response to a known radiation source.
Survey meter use. Use of Survey Meter review. Check for Calibration Sticker Check battery Check background radiation Check meter response to a known radiation source.
Meter Survey. You are now ready to perform your meter survey.
Meter Survey. Move detector face over area to be surveyed. (Slowly at rate of no more than one face diameter per second.) If you move too fast you will miss contamination. Hold detector face close to the surface, but never place detector face directly on surface. (This minimizes possibility of contaminating the meter.)
Meter Survey. Surveys should be performed after each use. Survey all locations and areas with the potential to become radioactively contaminated, including hands and shoes. Laboratory surveys must also be documented on either a weekly or monthly basis depending upon the isotope and frequency of use. Record your meter survey results on the lab survey form.
Meter Surveys and H-3 The beta particle emitted by the H-3 isotope is of such low energy (maximum energy of 18.6 keV and an average of 5.7 keV) that it can not be detected with a survey meter. Because of this, laboratories that are authorized for H-3 only ( and are not authorized for any other isotopes) are not required to do meter surveys. However they must still do post-use swipe surveys and the required documented swipe surveys.
Lab Survey Program (CONTINUED) SWIPE SURVEYS The purpose is to assess the removable portion of radioactive surface contamination. Evaluation of the REMOVABLE fraction of Surface Contamination assesses the potential for the inhalation or ingestion of radioactive materials. Analyze your wipe samples in a LSC or gamma well counter.
SWIPE SURVEYS An absorbent paper should be used to perform the wipe. Use the results of you meter survey to help determine where to conduct your swipe survey. For each wipe an area equal to 100 cm 2 should be wiped. Wiping a very large area may spread contamination. Analyze the wipes in a LSC or gamma well counter. Record the results on the lab survey form.
302 2 Sink3 Draw a map of your lab. Swipe areas where radioactive materials were used and areas that may have become contaminated. Number the swipe spot on your map. 3 4 5 6 3Hood6 4locker4 5Door knob0 6Floor2 Record the date and time of the survey. 6/10/09 11:35 Survey all locations and areas with the potential to become radioactively contaminated, including hands and shoes. Also any areas where your meter survey showed contamination. Record these locations on your map. Run the swipes in your LSC and record the results. Record your background counts. Record the swipe number. Record swipe location. Record swipe counts. Record all the swipe results. Fill in location. Building and room number. Dodgen210 This lab survey form is available at http://www.rso.wsu.edu/user radiation survey form.pdf http://www.rso.wsu.edu/user radiation survey form.pdf Record your meter survey results. All meter readings are at background levels.
SWIPE SURVEYS Survey frequencies Surveys should be performed after each use. Survey all locations and areas with the potential to become radioactively contaminated, including hands and shoes. Laboratory surveys must also be documented on either a weekly or monthly basis depending upon the isotope and frequency of use.
Test Time! Follow this link to the test. https://myresearch.wsu.edu https://myresearch.wsu.edu Use your WSU user name and password to sign in. Click on the training tab. Then click on the available training tab Find the Radiation safety training lab survey program, in the OR section, click on it and take the test.