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Threshold levels

Here presented results were acquainted predominantly by one-channel ten-level AE analyser IOC of the AED Laboratory Brno firm. This device is equipped by ten window threshold levels, defined fi-om top and bottom, the tenth level has not limitation fi-om top. Total dynamic range is 40 dB. The analyser enables continuous observation of total number of counts Nc, or number of counts per time unit and similar. Everything may be observed both in lull measured range and in individual levels. Range of measuring interval is SO ms up to 2500 ms. [Pg.62]

Channel AEBIL signal conditioning modules (variable amplifier, RMS measurement, floating threshold level, analog to digital conversion signal) ... [Pg.69]

Electromagnetic earthquake forerunners show themselves like the electromagnetic phenomena, including electromagnetic emission (EME) in a radio frequency range. This emission caused by collective exiting of the set of local mechano-electrical transformers (MET). The excitation mechanism inside the crust is determined by the fact that elastic tension ranges up to the threshold level within the source area. [Pg.914]

Table 2. Odor Detection Threshold Levels in Water and Mineral Oil, ppm... Table 2. Odor Detection Threshold Levels in Water and Mineral Oil, ppm...
The 1990 Clean Air Act Amendments Hst 189 hazardous air pollutants (HAPs) that the EPA must regulate to enforce maximum achievable control technology (MACT) to standards which are to be set by the year 2000. The 33/50 project calls for reduction of emissions of 17 specified solvents to predetermined levels by 1995. The SARA statute provides a mechanism by which the community can be informed of the existence, quantities, and releases of toxic chemicals, and requires that anyone releasing specific toxic chemicals above a threshold level to annually submit a toxic chemical release form to the EPA. The status of various ketones under these regulations is shown in Table 4. [Pg.488]

National Ambient Air Quality Standards. Under the Clean Air Act, six criterion pollutants, ie, pollutants of special concern, have been estabhshed by the EPA sulfur oxides (SO ), particulates, carbon monoxide (CO), nitrogen oxides (NO ), o2one (photochemical oxidants), and lead. National Ambient Air QuaUty Standards (NAAQS) were developed by EPA based on threshold levels of air pollution below which no adverse effects could be experienced on human health or the environment. [Pg.77]

Table 5. Odor Threshold Levels and Threshold Limit Values (TLV) ... Table 5. Odor Threshold Levels and Threshold Limit Values (TLV) ...
Chronic Toxicity Studies. With the exception of tumorigenesis, most types of repeated exposure toxicity are detected by subchronic exposure conditions. Therefore, chronic exposure conditions are usually conducted for the following reasons if there is a need to investigate the tumorigenic potential of a material if it is necessary to determine a no-effects or threshold level of toxicity for lifetime exposure to a material and if there is reason to suspect that particular forms of toxicity are exhibited only under chronic exposure conditions. [Pg.236]

Equipment and Economics A veiy large electrodialysis plant would produce 500 /s of desalted water. A rather typical plant was built in 1993 to process 4700 mVday (54.4 /s). Capital costs for this plant, running on low-salinity brackish feed were 1,210,000 for all the process equipment, including pumps, membranes, instrumentation, and so on. Building and site preparation cost an additional 600,000. The building footprint is 300 itt. For plants above a threshold level of about 40 m Vday, process-equipment costs usually scale at around the 0.7 power, not too different from other process eqiiip-ment. On this basis, process equipment (excluding the ouilding) for a 2000 mVday plant would have a 1993 predicted cost of 665,000. [Pg.2034]

Nonattainment area classification One-hour ozone concentration design value, ppm Attainment date Major source threshold level, tons VOGs/yr Offset ratio for new/modified sources... [Pg.2159]

Evidence suggests that there is a threshold tensile stress at which void nucleation occurs and spall fracture initiates. Materials subject to transient internal tensions can support tensile stresses significantly in excess of this threshold level, however. Such behavior is a consequence of kinetics and inertia associated with the nucleation and growth of voids during spall. A fairly large body of experimental and theoretical literature on spall phenomena exists and many aspects of the effect are reasonably well understood. Review articles on spall (Curran et al., 1977 Davision and Graham, 1979 Curran, 1982 Meyer and Aimone, 1983 Novikov, 1981) provide access to most of the literature on the subject. [Pg.267]

The main objective of air quality guidelines and standards is the protection of human health. Since fme particulates (PM,) are more likely to cause adverse health effects than coarse particulates, guidelines and standards referring to fine particulate concentrations are preferred to those referring to TSP, which includes coarse particulate concentrations. Scientific studies provide ample evidence of the relationship between exposure to short-term and long-term ambient particulate concentrations and human mortality and morbidity effects. However, the dose-response mechanism is not yet fully understood. Furthermore, according to the WHO, there is no safe threshold level below which health damage does not occur. [Pg.19]

Major Source a stationary facility that emits a regulated pollutant in an amount exceeding the threshold level (100 or 250 tons per year, depending on the type of facility). See also source. [Pg.536]

Audiogram The report produced by an audiometry test, showing measured hearing threshold levels at frequencies of 500, 1000, 2000, 3000, 4000, and 6000 Hz. [Pg.1415]

Temporary threshold shift (TTS) A temporary shift in hearing threshold level that goes away after the person has been in a quiet environment for a few hours. It is confirmed by an audiogram retest following a suspected standard threshold shift (STS) after at least 14 hours away from high levels of noise. [Pg.1481]

An inventory that includes the amount, nature, and location of any hazardous or extremely hazardous chemical present at a facility in an amount equal to or greater than its assigned threshold level . [Pg.1079]

For these reasons alloying elements appear in all the commercial anodes, and very careful quality control is required to keep disadvantageous tramp elements (notably iron and copper) below defined threshold levels. Many anode failures can be attributed to poor production quality control. A guide to minimum quality standards has been produced ... [Pg.119]

Where silicate levels are high (say, close to or above 150 ppm as Si02), the caustic alkalinity level must be at least 2.5 times the silica. At this level of alkalinity, any magnesium present will precipitate as a magnesium hydroxide sludge. Maintaining a high pH level also raises the solubility threshold level of silica. [Pg.413]

Much of our present day knowledge of sweetness intensity, both at the threshold level, where taste begins, and above the threshold level, derives from the application of psychophysical techniques. It is now evident that the psychophysical procedure used measure separate aspects of sweetness perception. Hedonic responses cannot be predicted from intensity of discrimination data, and vice versa. The taste-panel evaluation of sweetness is of fundamental importance in the development of worthwhile structure-taste relationships. Therefore, it is vital that the appropriate psychophysical method and experimental procedure be adopted for a particular objective of investigation. Otherwise, false conclusions, or improper inferences, or both, result. This situation results from the failure to recognize that individual tests measure separate parameters of sensory behavior. It is not uncommon that the advocates of a specific method or procedure seldom... [Pg.349]

A threshold level of oxygen storage (via bulk PdO) is required to reach Ngh CO/NOx conversion levels in dynamometer sweep tests Pd loading, rather than dispersion or surface area, is the most impoirtant factor affecting oxygen uptakes. [Pg.366]

Ultimately, all food and environmental analyses are conducted to safeguard human health and the environment. Methods are selected and applied based upon specific needs within this broader framework, including adherence to regulations, tolerances, threshold levels, etc. ... [Pg.6]

Step 8 Consider Adding Drug Therapy If LDL Is Above Threshold Level... [Pg.183]


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Hearing threshold level

Occupational threshold levels

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Threshold dose level

Threshold signal level

Threshold sound power level

Toxicity threshold levels

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