1 General and Historical Information

Oil and gas, in general, have been used since early human history to keep fires ablaze and also for warfare. The importance of oil in the world economy evolved slowly (Figure 1-1) (McKnight 1998). Wood and coal were generally used for heating and cooking. The Industrial Revolution subsequently generated an increasing need for energy, which was fuelled mainly by coal. During this period, it was discovered that kerosene could be extracted from crude oil and used as a light and heating fuel. Petroleum was in great demand by the end of the 1800s, and its use thus spread (Yergin 1992).

The 19^th century saw the development of the most technologically efficient means of transportation and the 20^th century the battle over control of transportation capital. In the present century, one of the challenges of the energy industry, in general, is the security of supply and, specifically for the pipeline industry, is the integrity and security of pipeline systems that constitute the most effective, environmentally friendly, and safe means of oil and gas transportation systems.

Pipeline networks are valuable assets, generally owned, operated, and maintained by pipeline companies. In any country, pipelines are an irreplaceable core of a hydrocarbon transportation system and means by which hydrocarbon fluids are delivered from the source of supply to the market area. It is of no coincidence that wherever there is the largest pipeline network, there is also the highest standard of living and technological progress.