Work Authorizations

DOE-STD-1136-2004

Guide of Good Practices for Occupational Radiological Protection in Uranium Facilitie s

energies. Most ion chambers used to measure photon radiations have a relatively flat energy response

above 80 to 100 keV; 137Cs or 60Co are typically used to calibrate these instruments. These sources also

should be used to calibrate Geiger-Mueller (GM) type detectors. It should be noted that some GM

detectors (e.g., those with no energy compensation) can show a large energy dependence, especially

below approximately 200 keV.

Whenever possible, beta detectors should be calibrated to the beta energies of interest in the

workplace. A natural or depleted uranium slab source can be used for calibration of beta detectors when

beta radiations in the workplace have energies similar to the uranium. International Organization for

Standardization beta sources should be used for all other purposes: the energy dependence of beta detectors

can be tested using the calibration sources listed in the ISO Publication 1980 (ISO, 1984); these include

Sr, 90Y, 204Tl, and 147Pm.

The calibration and testing of crucial monitoring systems are extremely important to the overall

radiation protection program, but have often been neglected. Effluent monitoring and sampling systems

(when present) and remote area monitoring systems should be given several tests. The radiological,

environmental, and mechanical characteristics of the instrumentation portion of the system should be fully

evaluated prior to its first use to ensure its compatibility with performance requirements and facility

operating conditions. The effluent sampling losses from the sample probe to the collector/detector should

be determined. This test should be repeated at least annually and when a significant change in the sampling

equipment is made. The sample probe should be examined at least once a year to verify its design or

performance has not been changed by corrosion. The recorder of the sample flow rate should be calibrated

when it is installed and annually thereafter. The operability of the overall system should be completely

tested once, with repeat tests only after modification, repair, or maintenance. Operability checks should be

scheduled at least monthly and calibration performed at least annually.

The operation of criticality or other radiation alarm signal systems should be checked periodically

to ensure the alarms are audible at all potentially occupied locations (ANSI 1986a). To prevent any

desensitizing of staff, the staff should be aware the tests will be performed, and where possible, tests should

be scheduled during off-shift hours. Building systems should be tested semiannually and the area-wide

system should be tested at least annually. Any portion of the detector/alarm system affected by the test

should be reconfirmed for operability after the test is completed (e.g., if a detector is disconnected and a

signal is injected at that point, the detector should be tested immediately after it has been reconnected).

3.2.6 Radiological Controls

3.2.6.1 Work Authorizations

Written authorizations shall be required to control entry into and work within radiological areas and

shall specify radiation protection measures commensurate with the existing and potential hazards (10 CFR

835.501(d)). ALARA considerations need to be included in the work authorization. One approach that

works well is the inclusion of an ALARA worksheet with the radiological work permit (RWP). Although

the written work authorizations may take any appropriate form (e.g., written procedures, policy statements,

technical work documents, etc.), RWPs are most often used. RWPs should be used for entry into high and

very high radiation areas, high contamination areas, and airborne radioactivity areas. RWPs should also be

used to control entry into radiation and contamination areas and for handling materials with removable

contamination. The RWPs should be initiated by the work group responsible

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