Blowing of natural gas lines

Finally the CSB has released a statement about natural gas blowing of pipelines. A survey has been conducted by CSB. "According to the survey, using natural gas to clean pipes remains the most common single practice in industry, employed by 37% of respondents. The other respondents reported using nitrogen, which is nonflammable, or inherently safer alternatives such as air, steam, or cleaning pigs. On February 25, 2010, eighteen days after the explosion at Kleen Energy, the CSB stated that natural gas blows were “inherently unsafe” and urged industry to seek alternatives".
Even last week, I had warned a natural gas user to prevent the blowing of lines with natural gas itself instead of using nitrogen. Read more of the CSB statement in this link.
Read my earlier post on the topic in this link.