"Myriad agencies have investigated BP's Gulf of Mexico oil spill, but the owner of the rig that exploded and sank wants to draw the line at the one designated by Congress to probe disasters involving deadly chemical blasts and releases."

T"he U.S. Chemical Safety Board, which investigates chemical explosions in the same manner the National Transportation Safety Board investigates airplane crashes, launched its first offshore investigation shortly after the 2010 explosion killed 11 workers and allowed more than 4 million barrels of crude to foul the gulf.

However, Transocean Ltd, which owned the Deepwater Horizon rig, says the agency has no jurisdiction to obtain access to blast survivors, internal records and other information as other agencies investigate oil spills. The CSB also had never investigated offshore incidents before, the company argued."

Kristen Hays reports for Reuters April 12, 2012. [2]