Radiation-emitting products

General medical devices are the responsibility of the Center for Devices and Radiological Health (CDRH). The CDRH is also responsible for assessing the safety of non-medical radiation-emitting products such as televisions, microwaves and mobile telephones. 

Radiation emitting products (e.g., cell phones, lasers)... 

The FDA is an agency within the PHS, which in turn is a part of the DHHS. The FDA regulates over 1 trillion worth of products, which account for 25 cents of every dollar spent annually by American consumers. The FDA touches the lives of virtually every American, every day, for it is FDA s job to see that the food we eat is safe and wholesome, the cosmetics we use will not harm us, the medicines and medical devices we use are safe and effective, and radiation-emitting products such as microwave ovens will not cause harm. Feed and drugs for pets and farm animals also come under FDA scrutiny. The FDA also ensures that all of these products are labeled truthfully with the information people need to use them properly. 

Performance standards for X-ray equipment are developed by the Food and Drug Administration under 21 CFR Part 1020, Performance Standards for Ionizing Radiation Emitting Products. Regulation oftheuse ofX-ray equipment is essentially left to the individual states and to the same health care industry group which monitors hospital quality control in many areas other than use of X-rays and radioisotopes, the Joint Council on Accreditation of Healthcare Organizations. 

Performance Standards for Ionizing Radiation Emitting Products, 21 CFR Chap 1, 1020.30, 1988. 

The radiation from a flame is due to radiation from burning soot particles of microscopic andsubmicroscopic dimensions, from suspended larger particles of coal, coke, or ash, and from the water vapor and carbon dioxide in the hot gaseous combustion products. The contribution of radiation emitted by the combustion process itself, so-called chemiluminescence, is relatively neghgible. Common to these problems is the effect of the shape of the emitting volume on the radiative fliix this is considered first. 

Another consideration in the determination of the optimum Eq is the depth of X-ray production in bulk samples, especially if one component strongly absorbs the radiation emitted by another. This is often the case when there is a low-Z element in a high-2 matrix, e.g., C in Fe. Here X rays from carbon generated deep within the sample will be highly absorbed by the Fe and will not exit the sample to be detected. The usual result will be an erroneously low value for the carbon concentration. In these situations the best choice for Eq will be closer to Eq with U rather than a much higher value with U = 2.5. 

The 02, radical can act as an oxidant as well as a reductant and chemical estimates of its production can also be based on its ability to oxidize epinephrine to adren-ochrome [62], These chemical methods have the additional advantage of not requiring highly specialized equipments. Also based on its redox property, the 02 radical can be determined by chemiluminescence methods through the measurement of the intensity of the fluorescence radiation emitted after chemical oxidation of 02 by, e.g., lucigenin [63-67], These methods, however, are limited by the poor selectivity and lack of capability for in-vivo performance. 

Fig. 12.21 shows the combustion products of AP-HTPB and RDX-HTPB composite propellants. Large amounts of H2O, HCl, and CO2 are formed when an AP-HTPB propellant composed of a.p(0.85) is burnt. The molecules of H2O, HCl, and CO2 each emit infrared radiation. On the other hand, no COj or C(g) is formed when an RDX-HTPB propellant composed of ri3x(0.85) is burnt. Instead, large amounts of CO, H2, and Nj molecules are formed as its major combustion products. However, no infrared radiation is emitted from H2 or N2 molecules. Though CO molecules are formed at ri3x(0.85), the infrared radiation emitted from these is less than that from H2O or CO2 molecules. 

This site contains information on the health effects and regulation of radiation-emitting devices and products. Protecting the public health by providing reasonable assurance of the safety and effectiveness of medical devices and by eliminating unnecessary human exposure to radiation emitted from electronic products. ... 

The use of certain surrounds (such as propane) eliminates or substantially reduces these luminosities which are undesirable if one is attempting to observe the radiation emitted by the deton products in the deton wave... 

The products were analyzed for chemically combined phenanthrene content by radio assay, based on the beta radiation emitted by the C atoms of the labeled phenanthrene. The radiation count rate of the labeled phenanthrene, measured under standard conditions, was used as a reference. The combined phenanthrene content of subsequent samples was calculated from a direct proportionality between the observed count rate of the samples and their labeled phenanthrene content. The beta radiation of the samples was counted with a thin-window (1.4 mg./sq. cm.) Geiger-Miiller tube and a scaler (Nuclear-Chicago Corp., Model No. 186.). 

If the radiation from the basin water to the still cover could be eliminated or substantially reduced, a large gain in productivity would be effected. To accomplish this, it would be necessary to have a cover, the underside of which would reflect long-wave radiation emitted by the water surface. The ideal cover would transmit all incoming radiation, both long- and short-wave length, and reflect all radiation emanating from the basin water. Because such a cover is theoretically not attainable, the next best... 

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