TRAINING - Training in Radiation Safety is required initially upon employment and annual refreshers thereafter. The Emory Radiation Safety Office offers a seminar to provide this training. We offer the seminar in the morning of the third Tuesday of each month, and the afternoon of the third Wednesday of each month. These seminars cover basic principle of radiation and radioactivity, the ALARA policy, surveys, contamination control and the biological effects of radiation. Our seminars last one to one-and-one-half hours and is followed by a short exam. A certificate is mailed to those attending.

Seminars are held in Room 306 of the old Dental School Building. Drop-ins are welcome, but if possible please register with the Medical Secretary, ext. 7-5922, or on the EHSO website (http://www.ehso.emory.edu)

WIPE TESTS - Record wipe tests results in DPM, or include the counter efficiency on your report. It's common knowledge that labs must record a wipe test each week. Many labs record the results of their survey in CPM, or counts per minute when the regulations require that the results be recorded in units of activity, such as uCi or more commonly, DPM or disintegrations per minute. Using CPM underestimates the amount of contamination due to counting losses. Many modern scintillation counters can display DPM, and if so, you should use those display options. Alternatively you can write the counter efficiency somewhere on the report, remembering that you would have slightly more contamination present, decontaminate at slightly lower CPM trigger levels. Efficiencies should be checked at least annually, and is often done during the annual preventative maintenance service. Typical efficiencies for counting in liquid scintillation cocktail are: 
 

H3:	55% - 65%
C14:	90% - 95% (also S35 & Ca45)
P32:	95% - 99%

and are determined primarily by comparing the activity of a known standard sample with the count rate observed from that sample:

Efficiency = Observed CPM/Known (true) DPM

from which we can calculate the true activity of a wipe or sample, once the efficiency has been determined:

Known (true) DPM = Observed CPM/Efficiency

mCerenkov and gamma counting efficiencies vary widely and should be determined for each situation.

INSTRUMENT SURVEYS - Record Geiger counter survey results in mR/h, or include the instruments' sensitivity on your report. If you use gamma or high energy beta emitters you must record an instrument survey each week, usually recorded on the same sheet as the wipe test. If you must use CPM instead of mR/h, also record the sensitivity which is stated on the meter's calibration sticker. Typical sensitivities are 1000 to 3000 CPM per mR/hr.

INVENTORY RECEIVED - Record the true activity received, rather than the activity ordered, if different. Many labs are using short - lived radioisotopes such as P32, S35, and I125. These isotopes are manufactured and packaged with an excess of isotope to allow for decay prior to sale and during transportation. When you order 250 uCi of P32 in a 100 microliter volume, and receive it one week before it's calibrated assay date, you would have actually received 354 uCi in the same 100 microliter volume. Also, some popular and economical solutions are sold for labeling cells with S35 in place of the more expensive S35 - Methionine, containing other S35 labeled compounds such as cysteine. The vendor sells you the methionine content of the mix, as in 5 mCi Tran S35, which actually contains 7.1 mCi of total S35 on its' calibration date; even more if delivered earlier. The Radiation Safety Office receives your packages, checks for contamination and then delivers the package to you. On the package is a label to indicate that no contamination was found, and the activity which the vendor states was shipped. This is the activity which you should record on your inventory for each shipment. You should also adjust the activities subsequently reported for experimental use, and for waste, accordingly.

AUDITABILITY - Maintain your records in an easily understandable style, to minimize audit errors. Keep a copy of your monthly inventory worksheet, your radioisotope use sheets (either the old style inventory sheets, or your personalized usage log), and your radioisotope waste inventory sheets. Keep your records organized by subject groups; worksheets in one section, wipes in another, etc. Keep your records in chronological order, and legible. Many of the forms we supply, such as wipe test forms, were designed carefully, so you should be completing each blank on the form. If a blank is not applicable, record N/A instead of no answer at all.

LABELS - Make sure your hoods, freezers, or other apparatus used with radioisotopes are labeled Radioactive' or Caution, Radioactive Material'. Waste containers should be labeled with the Investigator's name and the isotope. Suitable labels are available in the Radiation Safety Office.

NEED HELP? - To contact your Radiation Safety Office representative call (404) 727 - 5922 or visit us in Room 312.