Curtain board

Figure 16-6. Example of curtain boards for limiting fire spread in horizontal construction.

There is a need to provide vents within each area or section created by curtain boards. From knowledge of fire behavior and the development of a hot gas layer below a ceiling, an expression for the amount of vent area A required for a section is... 

Example 16-3 In a factory the curtain boards hang 10 ft from the ceiling. The bottoms of the curtain boards are 14 ft from the floor. The fire itself occurs within a 4 ft x 5 ft area. Assume that the hot gas layer formed along the ceiling extends half the distance to the bottom of the curtain boards, how much vent area is needed ... 

The area formed by combustibles in a manufacturing facility is 35 X 40 ft. There are curtain boards extending 12 ft from the ceiling that end 15 ft above the floor. What area of roof venting is needed between curtain boards... 

In large-area buildings, curtain boards are an important element, unless vented areas are subdivided by means of walls or partitions.The function of curtain boards is to delay and limit the horizontal spread of heat by providing the horizontal confinement needed to obtain the desired stack action. The depth of such curtain boards largely determines the height of the stack, which affects the capacity of the vent. If an area is protected by automatic sprinklers, curtain boards have added values confinement of heat to speed up operation of sprinklers over the fire and obstructed lateral spread of heat to minimize the operation of an excessive number of sprinklers. See Fig. 4.81. 

FIGURE 4.81 Curtain boards and roof vents. (From Fire Protection Handbook, 14th ed., G. P. McKinnon, ed., NFPA, Quincy, Mass., 1976.)... 

These coatings are applied by spray on more complex shapes, but on flat sheet or board roller coating is the preferred method, with curtain-coating used for thicker layers. 

The SSI (solid-state imaging) camera on board the Galileo spacecraft transmitted impressive high-resolution pictures of Io s volcanic activity. Active lava lakes, lava curtains , calderas, mountains and plateaus can be seen (McEwen et al., 2000). The Hubble telescope detected both S2 gas and SO2 in a SO2 to S2 ratio of 1 4 in the smoke trail of the volcano Pele. This value suggests an equilibrium between silicate magmas in the neighbourhood of the quartz-fayalite-magnetite buffer (see Sect. 7.2.2). 

A new type of background electrolyte feeding has now been proposed (P5). A horizontal channel, which has a series of small holes, provides a drip of electrolyte which falls onto the folded edge of the curtain. The folded edge lies on a drain board, and while the paper is able to suck the amount of water it needs, the excess flows from the drain board into... 

Fig. 53. Trickle feeding of the curtain. The gutter A, equipped with the ov flow O, trickles on the teeth cut in the upper edge of the curtain C through capillaries (Cap). Each tooth (T) of the curtain lies in a separate drain D of drain board (Db). All drains are collected in the general drain B.

Retardants are mainly used as additives for plastics, particularly those used in the manufacture of electrical and electronic equipment. FRs are added to circuit boards, cables, coimectors, plugs, and house component devices. These compounds are used in the production of engineering plastics, thermoplastic and elastomeric elements, and insulation. Flame retardants can also be found in furniture, mattresses, carpets, curtains, clothing (mainly protective or sweatshirts for children), and polymeric materials used for the production of cars, buses, airplanes, and military equipment. FRs have been used wherever material must meet safety standards regarding flammability [87]. 

Glass fiber mats and textiles are utilized in the manufacture of bituminous roofing felt and for carpet backing. Glass fiber textiles are also used in the manufacture of printed circuit boards and in the manufacture of grinding disks. Since they are non-inflammable, glass fibers are incorporated into noncombustible textiles such as fireprottf curtain fabrics. 

At the lack of proper ventilation, microbes can occupy practically any surface, WPC or not (Fig. 13.13). Several flat pieces of HOPE on my backyard were covered with green algae, namely the backsides, not accessible by the direct sunlight. No wonder, WPC can carry spots of mold when placed in a warm and wet environment, particularly with no draft. Mold grows even indoors, on shower bath plastic curtains. Even when no cellulose fibers are available for microbes (such as with flat pieces of neat HDPE), they consume pollen and other airborne particles. Brushed WPC boards always contain cellulose-derived dust on their surface. 

Asbestos is resistant to heat, moisture, chemicals, microorganisms, wear, deformation, and decay and insulates against noise, heat, and electricity. It has been widely used commercially in fabrics, paper, filters, fillers, insulating boards, cements, fireproof garments, curtains, shields, brake linings, shingles, pipe coverings, and moulded products. 

Applications coated fabrics, cornices, curtain rails, doorframes, guide rails for shutters, furniture profiles, roofing products, plastisol foams, shoe soles, skirting boards, sofit boards, wall and ceiling panelhng, wallpaper, window sills, wood-replacement products... 

Nevertheless, this is the most widely preferred of all methods. In these days, when so much furniture is made from pre-finished flat boards, the basecoat can be applied accurately in thin coats by roller coater and thus can contain higher solids. The finish is then applied by a curtain coater, which is positioned immediately after the roller coater on the production line. 

For purpose of this article only last case is analyzed. Entering into BSD activation area of arm is related to visual/audio alarm and stopping of transfer and in second stage into automatic arm release and spifling some amount of cargo. To minimize consequences of that kind accident constant water curtain is provided through board near manifold and dip trays are mounted at manifold area. 

Ammonium orthophosphate was first suggested as a fireproofing agent for theatre curtains by Gay Lussac [38] in 1821. The relatively cheap ammonium orthophosphates (mono, di or a mixture) (Section 12.2) were the first compounds to be used and they are still widely employed as fire retardants in paper, fibre boards, wood and fabrics where water solubility and susceptibility to leaching during washing is not important. 

Adhesives of the aminoplastic (see Step polymerization) and phenol formaldehyde (see Phenolic adhesives single-stage resoles and Phenolic adhesives two-stage novolacs) types are most widely used. Although basically similar, an adhesive for plywood manufacture will require a different formulation to one for particle board, or medium-density fibre board (MDF) since methods of application and processing differ. Thus, in plywood, large sheets of veneer must be uniformly coated with adhesive, usually by a roller or curtain coater in particle board, chips or wafers must be coated with very fine adhesive droplets, while small bundles of wet fibres must be sprayed with adhesive in the manufacture of MDF. Hence, formulation and production of resins has become a mixture of art and science, with resin manufacturers able to produce resins tailored for use in a particular board-manufacturing plant, or with a particular species of timber. 

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