Source smoke

Fig. 1-6. (Right) Pittsburgh before the decrease in black smoke. Source Allegheny County, Pennsylvania. (Left) Pittsburgh after the decrease in black smoke. Source Allegheny County, Pennsylvania...

If a hand is placed over the smoke source in Fig. 10.57, a wake region is created in the vertical flow field, as shown in Fig. 10.59,... 

FIGURE 12.4 Three examples of smoke sources line, surfece, and three-dimensional. 

Except for potassium, the composition of the soil aerosol at individual sites resembles the composition of the resuspended soil at the same site. The excess potassium is attributed to smoke sources. 

Wait 2 min and then advance the sample tube of the particle counter to a point directly under the smoke source and at the level of the work zone. Record the particle count. If it is not 100 per cubic foot or less, repeat the test with the wait interval increased in increments of 0.5 min until counts are less than 100 per cubic foot. 

If smoke is introduced with air pressure, adjust it to provide a smoke outlet velocity equal to the room air velocity at that point. Operate the particle counter with the sample tube at the normal work level and at a point remote from the smoke source. Verify that the counter indicates particle concentrations less than 200 particles of 0.5 ftm or greater. 

Move the sample tube in toward the smoke source from all directions at this level to the point where particle counts show a sudden and rapid rise to high levels (lO per cubic foot). This defines the envelope of dispersion away from the smoke source and demonstrates the airflow parallelism control of the room. Repeat for all grid areas. Prepare a diagram showing grid areas and corresponding dispersion envelopes. 

The degree to which dispersion away from the smoke source is conhned and the regularity of the pattern (indication of directional drift in one direction) is a matter of the configuration of the line. It is recommended that dispersion should not extend beyond 2 ft rapidly from the point of smoke source, i.e., at 2 ft from the generation point, the particle count should be less than 100 per cubic foot of the 0.5 fim size and larger. 

Molybdenum is also a smoke suppressant for poly(vinyl chloride). It promotes the formation of cis- rather than the trans-polymeric decomposition products which ate the precursors for smoke. The sources for molybdates ate Climax Performance Material Cotp. and Sherwin WiUiams. 

CAL 133. California Technical Bulletin 133 is a test of the fire hazard associated with upholstered furniture (22). The test is carried out by igniting a standard fire source directiy on the piece of furniture being tested. In the most recent version of the test, the fire source is a gas flame. Smoke, heat, and toxic gas emissions are measured dufing the test. A related test, BS 5852, uses various wooden cribs as the fire source (23). 

Sources of human exposure to formaldehyde are engine exhaust, tobacco smoke, natural gas, fossil fuels, waste incineration, and oil refineries (129). It is found as a natural component in fmits, vegetables, meats, and fish and is a normal body metaboHte (130,131). FaciUties that manufacture or consume formaldehyde must control workers exposure in accordance with the following workplace exposure limits in ppm action level, 0.5 TWA, 0.75 STEL, 2 (132). In other environments such as residences, offices, and schools, levels may reach 0.1 ppm HCHO due to use of particle board and urea—formaldehyde foam insulation in constmction. 

TSR 5. Within the Malaysian scheme SMR 5 is restricted to mbber derived from sheet material prepared by conventional processes, ie, ribbed smoked sheet (RSS), air-dried sheet (ADS), and unsmoked sheet (USS) and presented in small bale form. Other countries may source different raw materials, eg, Indonesia produces SIR 5 from thin latex coagulum (14). SMR 5 prepared by pressing dry-sheet material into standard bales must be identified by the type of sheet material, eg, SMR 5RSS, on the test certificate as well as on the wrapping. 

Workplace exposure limits for benzene have been regulated to levels as low as 0.5 ppm (43). Industrial emissions affecting the pubHc ate now low enough that the EPA considers that a greater hazard exists from mosdy indoor sources such as smoking, automobile exhausts, and consumer products (44). 

Occurrence. Carbon monoxide is a product of incomplete combustion and is not likely to result where a flame bums in an abundant air supply, yet may result when a flame touches a cooler surface than the ignition temperature of the gas. Gas or coal heaters in the home and gas space heaters in industry have been frequent sources of carbon monoxide poisoning when not provided with effective vents. Gas heaters, though properly adjusted when installed, may become hazardous sources of carbon monoxide if maintained improperly. Automobile exhaust gas is perhaps the most familiar source of carbon monoxide exposure. The manufacture and use of synthesis gas, calcium carbide manufacture, distillation of coal or wood, combustion operations, heat treatment of metals, fire fighting, mining, and cigarette smoking represent additional sources of carbon monoxide exposure (105—107). 

Fig. 1-3. A kiln for smoking red herring. Source H. L. Duhamel due Monceau, "Traite general des peches," Vol. 2, Sect. Ill, Plate XV, Fig. 1, Paris, 1772.

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