Contamination quality factor

Natural radionuclides contaminate air, food, and water. The annual per capita intake of natural radionuclides has been estimated to range from 2 Becquerels (Bq) for 232Th to about 130 Bq for 4 K (Sinclair 1988). The Bq is the International System of Units (SI) unit of radioactivity 1 Bq = 1 radioactive disintegration per second. The previously used unit of radioactivity is the Curie (Ci) 1 Ci = 3.7 x 1010 disintegrations per second, and 1 Bq = 27 x 10-12 Ci. The quantity of radiation or energy absorbed is expressed in Sievert (Sv), which is the SI unit of dose equivalent. The absorbed dose (in Gy) is multiplied by a quality factor for the particular type of radiation. Rem is the previously used unit for dose equivalent 100 rem = 1 Sv. 

Knowledge of plant cuticular components which modify insect behavior will be useful in the control of a given pest. When the component is not a valuable quality factor for consumer acceptance, breeding of plants that lack ovipositional stimulants will reduce pest damage. The use of plant breeding to increase levels of insect ovipositional stimuli could produce plants which will be useful as trap crops. This could lead to the reduction in the use of pesticides which increases production costs and environmental contamination. 

Color is another critical quality factor. It is subjectively evaluated by inspectors in a representative rice sample that has been previously milled using laboratory equipment. The color varies from desirable white to undesirable dark gray (Table 2.5). One of the most common off-colors is pink or rose, which results from the contamination of rice with red wild rice. The red pigments present in the aleu-rone-contaminated white kernels gives them a pink coloration. Parboiled rice is classified according to light or dark coloration. The hydrothermal process enhances color formation. 

An initial walkthrough of the problem area provides information about all four of the basic factors influencing indoor air quality (occupants, HVAC system, pollutant pathways, and contaminant sources). The initial walkthrough may provide enough... 

From the calibration point of view, manometers can be divided into two groups. The first, fluid manometers, are fundamental instruments, where the indication of the measured quantity is based on a simple physical factor the hydrostatic pressure of a fluid column. In principle, such instruments do not require calibration. In practice they do, due to contamination of the manometer itself or the manometer fluid and different modifications from the basic principle, like the tilting of the manometer tube, which cause errors in the measurement result. The stability of high-quality fluid manometers is very good, and they tend to maintain their metrological properties for a long period. 

The slushing material finds its most useful application on big machinery requiring protection of large areas during storage or during intervals of idleness in machine shops. The effect of dust and dirt contamination should therefore be considered an important factor in assessing the quality of these materials. 

Although the risk of scale deposition and fouling in the boiler section is related to several factors such as the FW volume demands, boiler pressure, and heat flux density at various boiler surfaces, it is equally a function of the level of FW contaminants such as residual hardness, sulfates, silica, and iron. Thus, as a generality, the higher the quality of FW (reduced levels of contaminants), the lower the risk of deposition on boiler surfaces. 

People are the principal source of contamination in clean room operations. All personnel involved throughout the development and production of a parenteral product must be aware of the factors that influence the overall quality of a product as well as the factors on which they directly impinge. It is of particular importance that production personnel be properly trained so that human error is minimized. They should be made aware of the use of the products with which they are involved and the importance of following all procedures, especially proper aseptic techniques. Procedures must be set up to verify that the product is being manufactured as intended. After manufacture of a batch, production tickets must be carefully checked, sterilization charts examined, and labels verified for correctness and count. 

It is unfortunate that many analytical chemists are required to work in laboratories which are far from suitable for the type of tests that they are required to perform. This can ultimately influence the quality of the results they produce. There are a number of factors that may influence the quality of analytical work. One important factor is that when a sample is being analysed to detect, e.g. very small amounts of the analyte of interest, it is essential to avoid all other sources of the analyte and other potentially interfering species which might contaminate the sample and distort the result. 

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