T.O. 33B-1-16-144f. A qualified radiographer shall be present at the control panel during all radiographic exposures and willbe the only person authorized to operate radiographic equipment. An operational, calibrated, surveyinstrument shall be available for immediate use by the radiographer during all radiographic operations.g. Except when making daily verification of safety interlock operation and in emergencies, door interlockswill not be used to terminate the exposure. The exposure shall be terminated at the control panel.h. When radiographic exposures have been competed, the safety-switch key shall be removed from thecontrol panel. The radiation-producing equipment and power safety-switch key shall be placed insecure areas separate from one another. Only radiographers specifically authorized by the Commandershall have access to the storage areas.6.9.18.2 Enclosed Installations (Air Force: N/A).6.9.18.2.1Featuresa. This class usually offers the greatest advantage for fixed installations with low use and low occupancyfactors. This is particularly true for high-energy sources where the reduction in shielding may result insignificant savings.b. The shielding requirements are considerably lower than for the protective installations, as much as 4.3half-value layers (HVL) less; yet, the inherent protection is such that the possibility of significantoverexposure is remote.c. With proper supervision, this class of installation offers a degree of protection similar to the protectiveinstallation.6.9.18.2.2Requirements.An installation shall be classified as "enclosed" when it conforms to all of the following mandatory requirements:a. The source of radiation and all objects exposed thereto are within a permanent enclosure, within whichno person is permitted to remain during irradiation.b. Each entrance that is used for personnel access to the enclosure/high-radiation area shall have bothvisible and audible warning signals to warn of the presence of radiation. The visible signal shall beactuated by radiation whenever the source is exposed/in operation. The audible signal shall be actuatedwhen an attempt is made to enter" the enclosure while radiation is being produced (10 CFR 34.29(b)).In addition, reliable dual independent interlocks are desirable on each door to prevent access to theenclosure during irradiation. A single interlock system on each door to prevent access to the enclosureduring irradiation is a mandatory requirement.c. Each of the following shall be provided (except where specifically noted) without regard to the sizeand/or configuration of the enclosure.NOTEA time delay interlock may be locally fabricated in order to meet this requirement.The suggested design is optional and not mandatory since numerous designapproaches can be used. Note that the wiring harnesses are similar to the harnessesused with X-ray Interlock Assembly, NSN 6635-00-292-7637. All time delayinterlock systems installed shall be compatible with all X-ray units commonlyavailable.
Integrated Publishing, Inc. - A (SDVOSB) Service Disabled Veteran Owned Small Business
