Asbestos: Where It Came From and Where It Is Used

Johns-Manville Corporation made this film, probably around 1970. It begins with the formation of the earth and of asbestos, the Greek name and its properties, then follows the ore from Canadian open-pit and underground mines through the crushers, screens and mill. It lists uses including textiles, cement pipe, shingles, asphalt paving, brake linings, gaskets, electrical paper and insulation, and says asbestos has been used on U.S. passenger ships since the 1934 Morro Castle fire.

What it says about asbestos and health

Nothing.

About this copy

Our copy is a transfer of a print from Johns-Manville's own film archive (box 04-03391), shown in full, 10:08 long.

Transcript

A machine transcript of the soundtrack, not yet checked against the film; names and technical words may be wrong.

What a wonder is this, our world, still fresh and new-looking after more than four and a half billion years in space. But we know, if we travel back far enough in time, that the seemingly ageless planet Earth has seen many changes. It had a violent beginning, so violent, in fact, that any solid minerals existing in the first billion years have long since vanished. Probably they were melted down in the heat, lost in the mists of early creation. Throughout the Earth's lifetime, the cooler surface has often yielded to the seething forces below. Over hundreds of millions of years, during which the surface formed a relatively thin crust, the continents and sea beds shifted thousands of miles in response to the upheavals of the underlying mantle and core.

In one dramatic example of volcanic activity, molten minerals violently forced their way to the surface, then cooled and hardened into rock so far a well-known geological story but then during further disturbances the hardened rock became fissured later scientists believe hot mineral bearing water flowed through the fissures dissolving some of the surrounding rock this solution crystallized into a network of fibrous veins from this unusual geological event came a a most unusual mineral. Even before the dawn of the Iron Age, it was already proving highly useful to man. The ancient Greeks, with their well- known curiosity, investigated it and found its fine fibers could be spun into yarn, and it resisted fire. The Greek word for this unique mineral was asbestos. Mineral asbestos is noncombustible, even at extremely high temperatures. It inhibits certain types of chemical reaction and is extremely flexible and durable.

All of these qualities combine to make asbestos especially suitable for a wide variety of demanding uses. Asbestos is the generic name given to a group of hydrated silicate materials that can be separated into relatively soft silky fibers which have greater tensile strength than many types of steel. Aside from small amounts produced in laboratories, man has never been able to duplicate its unique combination of physical, chemical, and textile properties in one mineral. In its natural state, most asbestos used in the United States is found in irregular crystalline veins. The name crude is applied to this cross-vein material before the fibers have been separated. The natural asbestos ore, or crude, is mined from open pit mines or underground mines, most of which are found in Canada.

When asbestos-bearing rock has been exposed, it is broken up by drilling and blasting with modern liquid explosives. Giant power shovels remove the ore-bearing rock. A fleet of giant trucks transport the ore from the mine. The separation of the asbestos fiber from the non-useful rock around it is done in the mill. First, the ore falls down the chute into the jaws of a primary crusher. Next, it moves to screens screens, and secondary crushers.

Asbestos- bearing rock is moved on conveyors to a distribution point at the top of a mill. After crushing, the crushed ore goes through a screening process to separate the fibers from the ore. Once the fiber has been obtained, asbestos combines easily with many other materials. Indeed, it is estimated that as many as 3,000 different products which contain some asbestos are in daily use throughout the world. While in certain products the percentage of asbestos may be small. The unique properties of asbestos usually are responsible for the functioning of the product in a demanding application.

Look around you. In the home and in the work environment asbestos is there. The heat resistant properties and fiber structure of asbestos make it extremely desirable as a fireproofing and insulating material in applications which already have prevented billions of dollars in property damage. Typically asbestos is used wherever fire and excessive heat heat are a threat to safety. As the needs of modern industry and modern living have expanded, asbestos has appeared in a wide range of applications suitable to its unique combination of properties. Long fibers are spun into yarn to lend strength and fire resistance to textiles.

Asbestos combines easily with many other materials. For example, with cement it is formed and cured to make strong corrosion-free pipe. Large diameter conduits tap water resources and convey waste water. The smaller diameters are installed for such uses as underground irrigation and sprinkler systems. Asbestos cement is also highly suitable as a building material, particularly for architectural siding. Asbestos cement shingles are dimensionally stable.

They provide fire and termite resistance, as well as strength and beauty for the roofs and siding of quality homes. Adding Adding asbestos to asphalt paving in airport runways, highways and bridge decks gives numerous benefits in durability and safety when a thin overlay of asbestos reinforced resurfacing asphalt is used. Asbestos is almost irreplaceable in friction materials such as brake linings on our cars. More than 80 million cars in the U.S. stop on asbestos brake liners which depend on the strength and heat resistance of asbestos. asbestos reinforcement also improves gasket materials asbestos is used to make many grades of paper including fine papers for electrical insulation protecting large generators high voltage transformers and everyday home appliances such as coffee pots asbestos is a principal ingredient in a wide variety of thermal insulating products such as the pipe insulation of this Arctic tanker. Because it is best known for its high resistance to extreme heat and fire, industry found many key uses. Pipe insulations have also been used for insulation and safety in the petroleum and chemical industries, and power generating plants, bringing essential energy to jobs and families.

New uses are constantly being developed. Here, an insulation containing asbestos is being applied to a high-gain antenna for use in outer space. The heat and fire resistant properties of asbestos are the most important reasons for its use in a wide range of products. The more asbestos finds its way into public buildings, the more people are able to find their way out when fire strikes. Asbestos is strong and non-combustible. On land it keeps the escape routes of buildings open when used to protect steel beams and provide a firewall between building sections.

At At sea, it protects ships' passengers and crew accommodations, since fireproof bulkheads reinforced with asbestos fiber have become the standard in ship construction. In fact, since the disastrous fire of the Morro Castle off New Jersey in 1934, asbestos has been used on U.S. passenger ships, and not one has been lost in a fire at sea since then. Without asbestos, steel structures would collapse more readily in fires. Brake linings would burn out in no time. Firefighters would be beaten back by flames instead of being able to walk right through them. And millions of BTUs of energy would be lost every day without asbestos in many forms of insulation.

On the surface of the earth or voyaging toward a distant planet asbestos plays a unique role no other material can equal.