Dive Brief:

• Two workers died Nov. 27 when the boom of a Liebherr LR11350 crawler crane crashed down while lifting a 420-ton roof section into place at a soccer stadium being built in Brazil for the 2014 World Cup.
• The boom separated from the base and fell outside the Arena Corinthians, which is under construction on the east side of Sao Paulo, where officials of the construction firm involved, Odebrecht, said work would resume Monday.
• The crane is rated for a maximum lift capacity of 1,350 long tons and was lifting the last section of roof into place when the boom came off.

Dive Insight:

Jim Wiethorn, who is a forensic specialist with Haag Engineering in Sugar Land, Texas, looked at photos of the scene and said the collapse was "highly unusual." He said it appeared that pins that hold the boom to the crane body were gone, but there did not seem to be any damage to the holes in which they should have been.