BUILDING MATERIALS SURVEY

Puilding lime may be quick or hydrated lime, but usually coimotes the latter, where the physical characteristics make it suitable for ordinary or special stmctural purposes (see Building materials, survey). 

Limestone and marble have been mined as building materials and the oxide of calcium, lime [1305-78-8], has been used ia the manufacture of mortar for centuries (see Building materials, survey Lime and limestone). Lime-burning was one of the first iadustries ia the American colonies, where calcining of limestone was accompHshed ia kilns dug out of the sides of hills. 

About 23 million metric tons of gypsum are consumed aimuaHy. About 80% is processed into the commercially usable hemihydrate. Uses of gypsum are ia fabricated and/or formulated building materials (see Building materials, survey), Pordand cement (qv) set regulation, and agricultural soil conditioning. 

Wood Preservation. The use of chromium compounds ia wood preservation is largely because of the excellent results achieved by chromated copper arsenate (CCA), available ia three modifications under a variety of trade names. The treated wood (qv) is free from bleeding, has an attractive ohve-green color, and is paintable. CCA is widely used, especially ia treating utility poles, bull ding lumber, and wood foundations. About 62% of all the chromic acid produced ia the United States is consumed by the wood preservation industry (77,167) (see Building materials, survey). 

Clays or shales that may be utilized ia the manufacture of bricks, tiles, and other heavy clay products exist ia every state ia the United States. (See Building materials, survey). Some blending of materials is often necessary to control shrinkage of the product, and the economics of manufacture are governed by the demands of fuel, labor, transportation costs, and the market. 

Clays composed of mixtures of clay minerals having from 20—50% of unsorted fine-grain nonclay materials are most satisfactory. Large amounts of iron, alkaHes, and alkaline earths, either in the clay minerals or as other constituents, cause too much shrinkage and greatiy reduce the vitrification range thus, a clay with a substantial amount of calcareous material is not desirable. Face bricks, which are of superior quaHty, are made from similar materials but it is even more desirable to avoid these detrimental components (see Building materials, survey). 

Fiber glass - [GLASS] (Vol 12) - [REINFORCED PLASTICS] (Vol 21) -borate m pORON COMPOUNDS - BORON OXIDES, BORIC ACID AND BORATES] (Vol 4) -borate m [BUILDING MATERIALS - SURVEY] (Vol 4) -for sound absorption [INSULATION, ACOUSTIC] (Vol 14) -use m ablative materials [ABLATIVE MATERIALS] (Vol 1) -use m conveying equipment [CONVEYING] (Vol 7) -use of oxygen for [OXYGEN] (Vol 17)... 

Gypsum [13397-24-5] - [CHEMICALS FROM BRINE] (Vol 5) - [PETROLEUM-DRILLINGFLUIDS] (Vol 18) - [FINE ARTEXAMINATION AND CONSERVATION] (Vol 10) - [ALCOHOLS,HIGHERALIPHATIC - SURVEY AND NATURALALCOHOLSMANUFACTURE] (Vol 4) -m barium carbonate mgf [BARIUM COMPOUNDS] (Vol 3) -m construction materials [BUILDING MATERIALS - SURVEY] (Vol 4) -hardness of [ABRASIVES] (Vol 1)... 

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