Fermi National Accelerator Lab (Fermilab) completed an extensive maintenance and development shutdown of its accelerators during autumn 2003. Shortly after resumption of operations in late November, a couple of unplanned cryogenic "quenches" led to unanticipated additional outages. However, this correspondent is glad to report that the accelerator complex at Fermilab is now achieving record luminosities for the Run II Tevatron Collider physics program and large intensities for the MiniBooNE experiment. Annual "productivity" goals are, at this point, largely being met. Obviously, these extensive shutdown tasks required a great deal of ALARA planning and execution, given the enhanced intensities now being used. While the accelerator improvements were all designed to produce improved reliability (less down time) and more intensity (more protons) for the machines, in reality the former nearly always translates into reduced dose. Furthermore, at Fermilab we are fortunate to have personnel at the highest levels of management, especially the director, who take safety in general, and radiation safety in particular, very seriously. As discussed in a previous article, this management involvement was very much evident. Here at Fermilab we are regarding this as an extremely successful example of the Department of Energy's (DOE's) Integrated Safety Management Program.
Now that we have the dosimetry results, it is clear that radiation exposures were well-controlled during the shutdown, and other types of safety-related events simply did not occur. The doses received doing the major tasks were within the expectations set forth during the planning of the individual job tasks. Obviously, there is a lag between the performance of work and the recording of doses on thermoluminescent dosimeter (TLD) "badges of record." At Fermilab, pocket ion chambers and, in high-dose situations, electronic dosimeters, are used as supplemental dosimeters to monitor and control exposures during work in order to provide immediate feedback. In early 2003, the Accelerator Division Radiation Protection Group led by Mike Gerardi and Gary Lauten worked collaboratively with the Accelerator Division Operations Department led by Bob Mau to set up a recording database for supplemental dosimeters. The participation by the Operations Department was of great assistance because of their management of Accelerator Division computers used in the dosimeter data collection as well as their responsibilities in the arena of access control. After some "debugging" needed to smoothly collect the dosimeter results for the other personnel present in addition to those who normally work in the Accelerator Division, this system now reliably collects dosimeter results. In fact, for the two calendar year (CY) quarters in which the shutdown occurred (CY 2003 3rd and 4th quarters), this database accounted for doses greater than 80% of the total for Fermilab during that period. This was a major achievement and one that corresponds with our general experience that the vast majority of personnel radiation exposures at Fermilab, and at most other accelerators, occurs during machine maintenance activities due to work on activated components. A written report concerning dosimetry experience at Fermilab during CY 2003 is in preparation and may be available, upon request, in the near future.
As most of our colleagues at DOE Office of Science accelerators know, the possibility of making a transition from self-regulation by DOE to "external regulation" by the U.S. Nuclear Regulatory Commission (NRC) and by the U.S. Department of Labor's Occupational Safety and Health Administration (OSHA) continues to be studied. To that end, short visits to Fermilab by representatives of both agencies were recently made to prepare for more extensive reviews to come later, probably during the autumn. The review by the Nuclear Regulatory Commission team occurred during late November. It was very favorable to the laboratory's radiation protection program. All the actions needed to come into compliance with NRC regulations that were identified by this team were traceable to places where DOE and NRC regulations differ explicitly. Due to the efforts of our entire staff, none were seen as deficiencies in good health physics practice. Should regulation of radiation protection by NRC come about, the action items consisted of those associated with the obtaining of a broad scope license, the need to establish a radiation safety committee and a radiation safety officer commissioned in accordance with NRC expectations, and some minor posting items. Two major issues related to control of access to radioactive materials and the posting of accelerator exclusion areas as "very high radiation areas" at times when beam could be present were identified. Cost estimates for these were provided, but it was understood that they could be reexamined should NRC-licensing actually come to pass. During March 2004, the OSHA review took place. Only minor radiological issues were found during that exercise and most related to the omnipresent one of "housekeeping," a problem that likely exists elsewhere.