Particulates measurements

Table 5. Summary of Detailed Particulate Measurements at Urban and Rural Locations...

Describe the deficiencies of a total suspended particulate measurement for relating ambient concentrations to potential human health effects. 

Black smoke (BS) is a particulate measure that typically contains at least 50% respirable particulates smaller than 4.5 mm in aerodynamic diameter, sampled by the British smokeshade (BS) method. The reflectance of light is measured by the darkness of the stain caused by particulates on a white filter paper. The result of BS sampling depends on the density of the stain and the optical properties of the particulates. Because the method is based on reflectance from elemental carbon, its use is recommended in areas where coal smoke from domestic fires is the dominant component of ambient particulates. 

In a report comparing community responses to low-level exposure to a mixture of air pollutants from pulp mills, Jaakkola et al. (1990) reported significant differences in respiratory symptoms between polluted and unpolluted communities. The pollutant mixture associated with the pulp mills included particulates, sulfur dioxide, and a series of malodorous sulfur compounds. Major contributors in the latter mixture include hydrogen sulfide, methyl mercaptan, and methyl sulfides. In this study the responses of populations from three communities were compared, a nonpolluted community, a moderately polluted community, and a severely polluted community. Initial exposure estimates were derived from dispersion modeling these estimates were subsequently confirmed with measurements taken from monitoring stations located in the two polluted communities. These measurements indicated that both the mean and the maximum 4-hour concentrations of hydrogen sulfide were higher in the more severely polluted community (4 and 56 g/m3 2.9 and 40 ppb) than in the moderately polluted one (2 and 22 g/m3 1.4 and 16 ppb). Particulate measurements made concurrently, and sulfur dioxide measurements made subsequently, showed a similar difference in the concentrations of these two pollutants between the two polluted communities. 

Particulate measurements on two boilers at a pulp and paper mill in Oregon showed similar results (59). The first boiler emitted 39 pounds per hour of particulate when burning hog fuel and 73 pounds per hour when 1 percent tdf was used. The other boiler showed 27 pounds per hour of particulate with 100 percent hog fuel, 46 pounds per hour with 1 percent tdf, and 57 pounds per hour with 1.5 percent tdf. 

The particulates in the SRC filter feed (after UOP filtration) appear to be predominately inorganic. The metals containing the particulates (calculated as oxides) account for almost all. In SRC, metal oxides could account for almost half of the particulates measured, especially if some fine particulates are reporting analytically to the filtrate instead of to the filter cake. 

Stahlberg ei a). [13] describe the development and rationale of non-isokineiic sampling systems when high flow rates are not possible and when particulate measurement is not to be performed simultaneously to gaseous species determination. 

Fig. 4 Particulate measurement in the dilution tunnel (arrangement based...

In the flue gas carbon monoxide and particulate shall be measured. CO-data can be used from the flue loss measurements. The data needs to be standardized to a given oxygen content (e.g. 13 vol %). If required also additional flue gas components can be analyzed such as nitrogen (NOx) and hydrocarbons (HC). The particulate measurements are done in the dilution tunnel. The particulate measurements shall not be interrupted during a bum cycle. 

For particulate measurements, the gas sample must be withdrawn isokinetically (see Section 7.3.1) to ensure that a representative sample of particles is withdrawn from the gas stream. If the extraction rate is too high, then the measured particulate concentration will be too... 

Parenteral formulations are often reconstituted or diluted in the clinic and hospital with standard solutions (e.g., 0.9% sodium chloride, 5% dextrose, and Ringer s solution). Compatibility with these diluents and administration sets, as well as in-use stability, should be evaluated. Co-administration of multiple drugs via a Y-site connection is common in hospitals. Precipitation, color change, decomposition or adsorption of the active drugs can occur. Turbidimetric and particulate measurements are often used for the evaluation of solution physical stability in addition to visual inspection [65]. 

An oxygenated hydrocarbon enhancer was also tested by co-injecting it with the urea-based chemical The co-injection resulted in 15% additional NOx reduction at lower temperatures (816-927 C or 1,5(X) - 1,7(X) F). Particulate measurement at the ESP showed that the urea-based SNCR had no effect on total particulate load or its collection efficiency. 

Required by CAA—200-300 sites measureing community pollutants quality of data spotty, poor hydrocarbon measurements particulates measured every 6th or 12th day mostly urban-suburban. Reported in SAROAD System. 

Accompanying these advances were essential developments in analytic and particulate measurement systems. These systems were required to test the innovations demanded by the makers and to validate the performance of these innovations in the field. Working with analytic instrumentation makers and particulate measurement hardware manufacturers, the industrial gases industry was able to dramatically advance the state of the art on measurement systems 54 ... 

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