Guidelines for beamline and front-end radiation shielding design at the Advanced Photon Source.

Fernandez, P. ; X-Ray Science Division

关键词: ADVANCED PHOTON SOURCE;    ALARA;    DESIGN;    DOSE EQUIVALENTS;    DOSE RATES;    MODIFICATIONS;    MONITORS;    PERSONNEL;    RADIATION MONITORS;    RADIATION PROTECTION;    RADIATIONS;    RECOMMENDATIONS;    SHIELDING;    STORAGE RINGS;   

DOI  :  10.2172/937419
RP-ID  :  ANL/APS/TB-44, REV. 3
PID  :  OSTI ID: 937419
Others  :  TRN: US0805797

美国|英语

来源: SciTech Connect

【 摘 要 】

Shielding for the APS will be such that the individual radiation worker dose will be as low as reasonably achievable (ALARA). The ALARA goals for the APS are to keep the total of the work-related radiation exposure (exposure coming from other than natural or medical sources) as far below 500 person-mrem per year, collective total effective dose equivalent, as reasonably achievable. For an individual APS radiation worker, the goal is to keep the maximum occupational total effective dose equivalent of any one employee as far below 200 mrem/yr as reasonably achievable. The ALARA goal for APS beamline scientists is to keep the total of the work-related radiation exposure (exposure coming from other than natural or medical sources) as far below 100 person-mrem per year, collective total effective dose equivalent, as reasonably achievable. For an individual APS beamline scientist, the goal is to keep the maximum occupational total effective dose equivalent of any one scientist as far below 50 mrem/yr as reasonably achievable. The dose is actively monitored by the radiation monitors on the storage ring wall in each sector and by the frequent area surveys performed by the health physics personnel. For cases in which surveys indicate elevated hourly dose rates that may impact worker exposure, additional local shielding is provided to reduce the radiation field to an acceptable level. Passive area monitors are used throughout the facility to integrate doses in various areas. The results are analyzed for trends of increased doses, and shielding in these areas is evaluated and improved, as appropriate. The APS policy for on-site nonradiation workers in the vicinity of the APS facilities requires that the average nonradiation worker dose be below 0.2 mSv/yr (20 mrem/yr). In addition, the dose at the site boundary from all pathways is required to be below 0.1 mSv/yr (10 mrem/yr). For future modifications of the facility, the doses shall be evaluated and additional shielding provided to meet the policy requirements.