Safety First: Intermodal Safety for Oil and Gas Transportation finds that transporting oil by pipelines is more than twice as safe as using rail, and marine tankers are safer still with a markedly improved safety record over the past 40 years. While oil shipped by tanker has increased from 1.4 billion tonnes in 1970 to 2.9 billion tonnes in 2015, the amount of spillage has plummeted by 98 per cent.