Monitoring field tests

For each field test, a procedure for the AE monitoring is established. 

The tests for insulation resistance and dielectric loss factor should, however, be carried out on a completed machine also with formed coils to establish reference data for field tests, as noted in Section 9.6. However, these tests on a completed machine with formed coils do not monitor the process quality of insulation. 

A simplification of the polarization resistance technique is the linear polarization technique in which it is assumed that the relationship between E and i is linear in a narrow range around E . Usually only two points ( , 0 are measured and B is assumed to have a constant value of about 20 mV. This approach is used in field tests and forms the basis of commercial corrosion rate monitors. Rp can also be determined as the dc limit of the electrochemical impedance. Mansfeld et al. used the linear polarization technique to determine Rp for mild steel sensors embedded in concrete exposed to a sewer environment for about 9 months. One sensor was periodically flushed with sewage in an attempt to remove the sulfuric acid produced by sulfur-oxidizing bacteria within a biofilm another sensor was used as a control. A data logging system collected Rp at 10-min intervals simultaneously for the two corrosion sensors and two pH electrodes placed at the concrete surface. Figure 2 shows the cumulative corrosion loss (Z INT) obtained by integration of the MRp time curves as ... 

The airflow equations presented above are based on the assumption that the soil is a spatially homogeneous porous medium with constant intrinsic permeability. However, in most sites, the vadose zone is heterogeneous. For this reason, design calculations are rarely based on previous hydraulic conductivity measurements. One of the objectives of preliminary field testing is to collect data for the reliable estimation of permeability in the contaminated zone. The field tests include measurements of air flow rates at the extraction well, which are combined with the vacuum monitoring data at several distances to obtain a more accurate estimation of air permeability at the particular site. 

Crockett, A.B. Hern, S.C. Kinney, W.L. Flatman, G.T. "Guidelines for Field Testing Aquatic Fate and Transport Models Interim Report" U.S. Environ. Prot. Agency, Environ. Monitoring Systems Lab. Las Vegas, Nevada, 1982 p. 174 + Appendices. 

As part of the radon program at EML to develop or improve and field test radon monitors, a modified activated carbon device (Warner, 1986) was developed to obtain higher measurement sensitivity. As a result, we have surveyed 380 buildings in six states in the eastern United States. The purpose of the measurements reported in this paper was to test the feasibility of the new version of the passive activated carbon device and to obtain data on indoor radon levels in different geographical locations. 

The analytic principles that have been applied to accumulate air quality data are colorimetry, amperometry, chemiluminescence, and ultraviolet absorption. Calorimetric and amperometric continuous analyzers that use wet chemical techniques (reagent solutions) have been in use as ambient-air monitors for many years. Chemiluminescent analyzers, which measure the amount of chemiluminescence produced when ozone reacts with a gas or solid, were developed to provide a specific and sensitive analysis for ozone and have also been field-tested. Ultraviolet-absorption analyzers are based on a physical detection principle, the absorption of ultraviolet radiation by a substance. They do not use chemical reagents, gases, or solids in their operation and have only recently been field-tested. Ultraviolet-absorption analyzers are ideal as transfer standards, but, as discussed earlier, they have limitations as air monitors, because aerosols, mercury vapor, and some hydrocarbons could, interfere with the accuracy of ozone measurements made in polluted air. 

Advanced electro-optical methods (e.g., laser resonance absorption) capable of measuring average concentrations over long distances still requite extensive research and field testing to demonstrate their practical application to ozone monitoring. Because electro-optical methods have not yet been widely used, they are not discussed further here. 

In both of these field tests, the application of thin-layer chromatography was essential for characterizing the pesticides in the water and in monitoring the progress of their removal by the carbon filtration system. 

Of more practical concern are some examples of field test data obtained with the 3M Organic Vapor Monitor. In addition to the examples given below, many other comparative studies, performed both in the laboratory and in the field, by companies and agencies other than 3M are available. Copies may be obtained from 3M upon request. 

This paper reports on research involved the design, construction, and evaluation of a portable instrument, a "luminoscope", for detecting skin contamination by coal tars via induced fluorescence. The instrument has been used in the laboratory to measure the fluorescence of various coal tars and recycle solvents from liquefaction processes spotted on filter paper on rat and on hamster skin. The practical use of the devices in field test measurements to monitor skin contamination of workers at coal gasifier is discussed. The paper also discusses the practicality and usefulness of the luminescence method for detecting skin contamination. 

Monitoring skin contamination at a coal gasifier. Recently the luminoscope was field tested at a coal gasifier facility. The purpose was to evaluate the performance of the prototype apparatus in a real-life workplace environment and to test the applicability of the instrumental concept in actual measurements. The skin contamination survey was carried out on six workers during two work-shifts. All measurements were carried out before and after washing. The portions of the workers bodies most likely to be directly exposed to coal and tar are those not protected by clothing, e.g., hands, arms, and faces. The measurements performed during this field trip were restricted only to arms and hands. 

This paper describes the luminoscope, a simple laboratory-constructed, portable luminescence detector designed specifically for monitoring occupational skin contamination. The instrument design is based upon a fiberoptics waveguide. The instrument is suitable for detecting trace amounts of various coal tars and has recently been field tested at a coal conversion facility. 

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