Gamma Radioactivity Detection Limits and Associated Radionuclide Intakes Study in Artificial Human Urine Using Sodium-iodide and High-purity Germanium Detectors.

The performance of several gamma detectors was investigated for emergency urine bioassay screening of two radionuclides of concern: 131 I and 137 Cs. Unspiked artificial urine samples were measured for 10 min each on four different gamma detectors: 80% relative efficiency high-purity Ge detector in standard shielding, 102% low-background high-purity Ge detector equipped with top muon shield, 78% high-purity Ge well detector in standard shielding, and 4″ × 4″ NaI well detector in standard shielding. The measured gamma spectra were analyzed in two ways: (1) for the 364-keV peak region of 131 I and 662-keV peak region of 137 Cs and (2) for the total counts in the full energy spectrum (50-2,048 keV).

Long-term monitoring of radioactivity in fish from New York waters.

As part of an environmental surveillance program operated by the New York State (NYS) Department of Health, measurements of various radionuclides in aquatic life (primarily fish) collected from waterways in NYS have occurred for decades. An investigation was undertaken to gain a better understanding of the occurrence, activity levels, and extent of radionuclide variations in aquatic life obtained from local waterways in relation to concentrations reported in fish from sites outside NYS (e.g.

Radon measurement of natural gas using alpha scintillation cells.

Due to their sensitivity and ease of use, alpha-scintillation cells are being increasingly utilized for measurements of radon ((222)Rn) in natural gas. Laboratory studies showed an average increase of 7.3% in the measurement efficiency of alpha-scintillation cells when filled with less-dense natural gas rather than regular air.

Emanation of radon from household granite.

Emanation of radon (222Rn) from granite used for countertops and mantels was measured with continuous and integrating radon monitors. Each of the 24 granite samples emitted a measurable amount of radon. Of the two analytical methods that utilized electret-based detectors, one measured the flux of radon from the granite surfaces, and the other one measured radon levels in a glass jar containing granite cores.

Performance of a commercial radon-in-water measurement kit.

Methods currently approved for the measurement of radon ((222)Rn) in water in New York State are liquid scintillation counting and emanation into alpha-scintillation cells. A passive system using an electret ion chamber (EIC) was evaluated as an alternative for the measurement of radon in water. Over 130 water samples from a community water supply containing 32BqL(-1) and 30 standards containing 686BqL(-1) were measured using the EIC method over 1- to 4-day exposure times.

Radioactivity in trinitite six decades later.

The first nuclear explosion test, named the Trinity test, was conducted on July 16, 1945 near Alamogordo, New Mexico. In the tremendous heat of the explosion, the radioactive debris fused with the local soil into a glassy material named Trinitite. Selected Trinitite samples from ground zero (GZ) of the test site were investigated in detail for radioactivity.