Ship-breaking (also known as ship recycling, ship demolition, ship dismantling, or ship cracking) is a type of ship disposal involving the breaking up of ships for either a source of parts, which can be sold for re-use, or for the extraction of raw materials, chiefly scrap. Modern ships have a lifespan of 25 to 30 years before corrosion, metal fatigue and a lack of parts render them uneconomical to operate. Ship-breaking allows the materials from the ship, especially steel, to be recycled and made into new products. This lowers the demand for mined iron ore and reduces energy use in the steelmaking process. Fixtures and other equipment on board the vessels can also be reused. While ship-breaking is sustainable, there are concerns about the use by poorer countries without stringent environmental legislation. It is also labour-intensive, and considered one of the world's most dangerous industries. In 2012, roughly 1,250 ocean ships were broken down, and their average age was 26 years. In 2013, the world total of demolished ships amounted to 29,052,000 tonnes, 92% of which were demolished in Asia. As of January 2020, Alang Ship Breaking Yard (India) has the largest global share at 30%, followed by Chittagong Ship Breaking Yard (Bangladesh) and Gadani Ship Breaking Yard (Pakistan). The largest sources of ships are China, Greece and Germany, respectively, although there is a greater variation in the source of carriers versus their disposal. The ship-breaking yards of India, Bangladesh, China and Pakistan employ 225,000 workers as well as providing many indirect jobs. In Bangladesh, the recycled steel covers 20% of the country's needs and in India it is almost 10%. As an alternative to ship-breaking, ships may be sunk to create artificial reefs after legally mandated removal of hazardous materials (though this does not recycle any materials), or sunk in deep ocean waters. Storage is a viable temporary option, whether on land or afloat, though most ships will be eventually scrapped; some will be sunk, or preserved as museums. History Wooden-hulled ships were simply set on fire or "conveniently sunk". In Tudor times (1485–1603), ships were dismantled and the timber re-used. This procedure was no longer applicable with the advent of metal-hulled boats in the 19th century. In 1880 Denny Brothers of Dumbarton used forgings made from scrap maritime steel in their shipbuilding. Many other nations began to purchase British ships for scrap by the late 19th century, including