We extended our deepest condolesences to a victim.

A victim had fatal damage on his head due to explosion.

Jennie Runevitch, WTHR reporter  said that  victim as 48-year-old Jim Gibson, died of blunt force trauma to his head due to multiple skull fractures.  

and 

According to OSHA and the U.S. Department of Labor, the plant has been fined twice for violations in the past ten years in 2009 and 2004.

[http://www.wthr.com/story/25917537/2014/07/01/injuries-reported-in-explosion-at-marion-general-motors-plant]

The Marion plant was ranked at the very bottom of GM for safety in terms of lost workdays and near-miss accidents.

[https://www.wsws.org/en/articles/2014/07/03/mari-j03.html] 
--> The page was deleted from the web site (July 5th) Access: July 4th

Click on the PDF to open the deleted web site.

http://www.youtube.com/watch?v=Ex-76tX2OHw

[NOTE]

Overpressure is one of the key parameters to estimate severity to the body.