Configured to provide gamma dose rates over four orders of magnitude, the gamma irradiation facilities have been used extensively for food irradiation studies, developing optimized radiation doses for medical product sterilization, and radiation effects evaluations on electronic components and other materials such as optical components (mirrors, lenses, and windows) for space applications. Biomedical studies have focused on radiation induced cross-linked polymers for medical applications in tissue engineering and improved prostheses. Other studies include radiation effects on plastics used in the treatment of cancer.

High-Dose Rate Facilities

>Gamma Cave
This facility is an irradiation room having an equi-dimensional volume of 512 cubic feet. A wide range of dose rates, 1Gray (100 rad) per hour to 10,000 Gray (1 Mrad) per hour, is available. Several small ports penetrate one shielding wall to provide access for instrumentation cables.
Uses: bulk sterilization, bulk material evaluation, electronic component evaluation.

>Submersible Canister

For high total integrated doses, the Submersible Canister (SubCan) is an ambient temperature, watertight chamber, having dimensions 20.3 cm (8 in.) I.D. x 30.5 cm (12 in.) provides a maximum dose rate of 20 kGray/hour (2 MRad/hour). Dose distribution variations of less than 10% are achievable for most samples.
Uses: sterilization, material enhancement, material qualification.

>Small Sample Irradiator

For smaller samples requiring high doses, the Small Sample Irradiator (SSI) can provide a maximum dose rate of 20 kGray/hour (2 Mrad/hour). The internal dimensions of each irradiator are 2.4 cm (15/16 in.) x 21.9 cm (8 5/8 in.) x 33 cm (13 in.).
Uses: sterilization, material enhancement, structural material evaluation.

Low-Dose Rate Facilities

>Enhanced Low Dose Response

The Enhanced Low Dose Response (ELDR) facility consists of four independent irradiation chambers providing dose rates less than 0.01 Rad/s (36 Rad/hr) and having a uniform photon flux distribution. Penetrations for test cables and a large area for test equipment are available. If needed, higher dose rates are available for this facility.
Uses: electronic component evaluation.

>Hot Cell

Originally designed for radioisotope sample preparation, this facility presently houses a shielded irradiator. The irradiator provides up to two gamma beams permitting dose rates 0.1 Gray to 5 Gray per hour (10 to 500 Rad/hour). The facility also provides a remote operated overhead crane, remote robotic manipulators, a shielded view port, and multiple conduit ports.
Uses: electronic component evaluation.

N-16 Calibrator

For purposes of high-energy photon calibration, the field of photons from the calibrator has been well characterized for purposes of dosimetry-related measurements. Useful for evaluating responses of ionizing radiation dosimeters and instruments to N-16 photons, in particular for nuclear plant personnel protection. Dose equivalent rates up to 300 mrem/hr are available.

>Quality Assurance
Accurate radiation exposure is assured by using aminotriphenylmethan/optichromic dosimetry (Far West Technology) and alanine/EPR (Bruker) dosimetry systems. A Quality Assurance Program meeting the requirements of 10CFR Part 50 Appendix B provides for the performance and maintenance of gamma dosimetry calibration traceable to the National Institute of Standards and Technology.

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