Radiostrontium in the Savannah river site environment.

The Savannah River Site has produced plutonium, tritium, and other special nuclear materials for national defense, other government programs, and some civilian purposes. Strontium has been released to the environment during the operation of five reactors, two radiochemical processing facilities, and other supporting facilities. During the period 1954-1996, 110 GBq of 90Sr were released to the atmosphere and 5,400 GBq were released to site streams. The maximum individual effective dose equivalent at the site boundary was estimated to be 72 microSv from atmospheric releases and 25 microSv from liquid releases. The 80-km population dose was 0.3 person-Sv.

Plutonium in the Savannah River Site environment.

The Savannah River Site has produced plutonium, tritium, and other special nuclear materials for national defense, other government programs, and some civilian purposes. Plutonium has been released to the environment during the operation of five reactors, two radiochemical processing facilities, and other supporting facilities. During the period 1954-1989, 140 GBq of plutonium were released to the atmosphere and 23 GBq were released to site streams and ponds. The maximum individual effective dose equivalent at the site boundary was estimated to be 120 microSv from atmospheric releases and 2.4 microSv from liquid releases. The 80-km population dose was 7.1 person-Sv.

Radiocesium in the Savannah River Site environment.

The Savannah River Site has produced plutonium, tritium, and other special nuclear materials for national defense, other government programs, and some civilian purposes. Radiocesium, a waste product, has been released to the environment during the operation of five reactors, two radio-chemical processing facilities, and a high-level waste storage system. During the period 1955-1989, 130 GBq of 137Cs was released to the atmosphere and 2.2 x 10(4) GBq was released to site streams and ponds. Approximately 65% of the latter remained on the site. The maximum individual effective dose equivalent at the site boundary was estimated to be 3.3 microSv from atmospheric releases and 600 microSv from liquid releases. The 80-km population dose was 1.6 person-Sv.

Environmental monitoring and dose assessment following the December 1991 K-reactor aqueous tritium release.

Between 22 December and 25 December 1991, approximately 570 L of tritiated water was released from the K Reactor at the Savannah River Site. Analyses of river flow rates and measured tritium concentrations showed that approximately 210 TBq of tritium had been released from the reactor and was being transported down the Savannah River. Elevated tritium concentrations in the Savannah River were first detected on 26 December 1991. The maximum measured tritium concentration at Highway 301 (a major sampling point 37 km downstream of the Savannah River Site) was 2.5 Bq mL-1. A hypothetical maximum individual located at Highway 301 would have received a drinking water dose of approximately 0.35 microSv, less than 1% of the Environmental Protection Agency's 40 microSv y-1 drinking water standard. Concentrations at the intake canals to two water treatment facilities, approximately 160 km downstream, began to rise above normal on 28 December. The population dose to users of the downstream domestic water supplies and consumers of Savannah River biota was estimated to be 4.7 x 10(-3) person-Sv.

Economic impact of quality control in diagnostic radiology.

With ever-increasing costs confronting health care facilities, much attention is being focused on various cost-containment projects. Although it is generally assumed that a radiology department quality control program will increase costs, institutional savings may also result. A comprehensive quality control program involving continuing education, simplification of technic, processor control, standardization of cassettes, and preventive maintenance resulted in substantial savings for a medical school radiology department.

X-ray attenuation by prescription lenses.

The degree of attenuation of diagnostic x-rays by prescription lenses is reported. Photo-gray lenses provide considerable eye protection.

Performance evaluations for diagnostic x-ray equipment.

Technical factors influencing the performance of x-ray equipment are: focal spot size, focal spot growth, leakage radiation, accuracy of the exposure timer, kilovoltage, exposure reproducibility, linearity of exposure, x-ray beam quality, and collimation. An evaluation of these factors is necessary to determine x-ray equipment performance characteristics.

Radiation exposure during panoramic radiography in children.

In an effort to determine the amount of radiation exposure a child receives during a panoramic radiograph and to evaluate the effect of a protective thyroid collar, dosimeter readings were made on twenty-nine child patients at fourteen anatomic sites. The levels of radiation recorded were similar to those previously recorded for adults and phantoms, except for greater doses in the thyroid area. Placement of a lead-lined thyroid collar resulted in significant reduction of the thyroid doses.

Corneal contact times of ophthalmic vehicles. Evaluation by microscintigraphy.

Lacrimal microscintigraphy, in conjunction with a recently developed computer system, was used to evaluate the corneal contact time of three ophthalmic vehicles in 18 humans. The percentage of a radioactively labeled vehicle remaining over the cornea after 90 seconds was 2.9% plus and minus 2.2% for saline, 4.3% plus and minus 2.4% for polyvinyl alcohol, and 8.8% plus and minus 4.1% for hydroxypropyl methylcellulose.