Researchers suggested that the reduction was largely a result of equipment upgrades, including replacement of leaky old cast-iron or unprotected steel pipe.<div><a href="http://www.nytimes.com/2015/04/01/science/earth/gas-utilities-reduce-leaks-of-methane-study-finds.html?partner=rssnyt&amp;emc=rss" target="_blank">Original link</a></div><div>Original author: JOHN</div>