Wool dust

Urea-formaldehyde insulation foam Wool dust... 

Both wool and grain dust samples were capable of stimulating TNF release from rat alveolar macrophages isolated by bronchoalveolar lavage, in a dose-dependent maimer (Brown and Donaldson 1996). Leaches prepared from the dusts contained LPS and also caused TNF release but leachable LPS could not account for the TNF release and it was clear that non-LPS leachable activity was present in the grain dust and that wool dust particles themselves were capable of causing release of TNF. 

Brown and Donaldson (1994), however, suggested that the alveolar macrophages of HAN rats after intratracheal instillation of 1 mg of wool dust collected from two wool mills in the North of England, with increased secretion of immunostimula-tory cytokines, could be migrating to the lymph nodes, stimulating the local lymphocytes in the node. 

Lucas and Porter (U.S. Patent 3,370,401, 1967) developed a fiber-bed scrubber in which the gas and scrubbing liquid flow vertically upward through a fiber bed (Fig. 17-55). The beds tested were composed of knitted structures made from fibers with diameters ranging From 89 to 406 [Lm. Lucas and Porter reported that the fiber-bed scrubber gave substantially higher efficiencies than did venturi-type scrubbers tested with the same dust at the same gas pressure drop. In similar experiments, Semrau (Semrau and Lunn, op. cit.) also found that a fiber-bed contactor made with random-packed steel-wool fibers gave higher efficiencies than an orifice contactor. However, there... 

Dust and fume masks eonsist of one or two eartridges eontaining a suitable filter (e.g. paper or resin-impregnated wool) to remove partieulate eontaminant. The effieieney of the filters against partieles of various sizes is quoted in manufaeturers literature and national standards. Sueh masks do not remove vapour from the air. 

Wool Resists rapid penetration of direct splashes (more effective than cotton) Resists penetration of dust High absorption and porosity absorbs perspiration Not resistant to hot splashes Takes up water and dirt Difficult to wash ... 

Figures 4-65, 4-66, and 4-67 show several units of the bag. The bags may be of cotton, wool, synthetic fiber, and glass or asbestos with temperature limits on such use as 180°F, 200°F, 275°F, 650°F respectively, except for unusual rnaterials. (See Table 4-12A and B.) These units are used exclusively on dry solid particles in a gas stream, not being suitable for wet or moist applications. The gases pass through the woven filter cloth, depositing the dust on the surface. At intervals the unit is subject to a de-dust-ing action such as mechanical scraping, shaking or back-flow of clean air or gas to remove the dust from the cloth. The dust settles to the lower section of the unit and is removed. The separation efficiency may be 99%-i-, but is dependent upon the system and nature of the particles. For extremely fine particles a precoat of dry dust similar to that used in some wet filtrations may be required before re-establishing the pi ocess gas-dust flow.

Mica Mineral wool fibre 3 (respirable dust) 10 " ... 

Substances that can irritate the skin or mucus membranes of the respiratory tract pollen, moth balls, steel wool, fiber glass, potassium permanganate Wear dust mask and gloves. Practice extra care when handling these materials. Go to your teacher for first aid. 

The lower explosive limit and minimum explosive concentrations of flax, wool, cotton, jute, hemp and sisal fibres are of the same order of magnitude as those of highly explosive dusts [15], The explosibility of pyrites dusts with sulfur contents above 20% was evaluated experimentally. Dusts of 30% sulfur content gave explosion pressures of 3 bar at pressure rise rates of 16 bar/sec. Mixtures of 60% pyrites and 40% powdered limestone still showed significant pressure effects, and the proportion of limestone actually needed to suppress explosions was considerably above the values currently accepted by mining industries [16], Effects of mixtures of particle sizes in combustible dusts upon minimum ignition temperature (T ") and upon presence or absence of explosion were studied. Presence of 30% of fines in a coarse dust lowers Tf significantly [17], Experimental explosions of polyethylene,... 

A variety of different types of collectors may be used, depending on circumstances. Dry collectors, for example, are widely used in different types of plants and are suitable for conditions where the dust is relatively free from moisture. They can be installed and operated at medium cost and high efficiency. They are normally located outside the plant and are made up of a box with an inverted conical base or hopper. Inside the box are hung a number of tubular or envelope-shaped filters through which the air is passed. The filters may be made of cotton, wool, paper, glass cloth, or synthetics. Dust is built up on the filters until the resistance to flow... 

Clnkotal et al. (11) sampled the total airborne dust (Andersen impactor) In the cardroom of sevel cotton spinning mills and showed 1500 to 11,500 fungl/m3. Cotton waste mills, a wool mill, and a tea packing factory had similar numbers of fungi while wil-lowlng mills had 22,500 fungi/m. ... 

Clnkotai (33) in 1976 reported that byssinosis correlates with the activity of trypsin-like enzymes in cardroom dust and with the concentration of 1-2 ym, and 2-4 ym particle fractions. These fractions contained the viable microorganisms carrying pro-tealytic enzymes. The enzymes were also present in wool mills (no byssinosis) but were considered to be encapsulated in microorganisms. ... 

Environment and health-related problems are dominated by risks emanating from fibre dusts, which are released during the production and processing of mineral wool products and in refurbishment and/or demolition work. If the fibres are sufficiently small and are inhaled, they can enter the lung. They can also induce skin and respiratory diseases and some are also potentially carcinogenic. 

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