But the internal documents, including dozens of memos, e-mail messages and reports from the Army, the Defense Contract Management Agency and other agencies, show that electrical problems were widely recognized as a major safety threat among Pentagon contracting experts. It is impossible to determine the exact number of the resulting deaths and injuries because no single document tallies them up. (The records were compiled for Congressional and Pentagon investigators and obtained independently by The Times.)

The 2007 safety survey was ordered by the top official in Iraq for the Defense Contract Management Agency, which oversees contractors, after the October 2006 electrical fire that killed two soldiers near Tikrit. Paul Dickinson, a Pentagon safety specialist who wrote the report, confirmed its findings, but did not elaborate.

Senior Pentagon officials appear not to have responded to the survey until this May, after Congressional investigators had begun to ask questions. Then they argued that its findings were irrelevant to Sergeant Maseth’s electrocution.

In a memo dated May 26, 2008, a top official of the Defense Contract Management Agency stated that “there is no direct or causal connection” between the problems identified in the survey and those at the Baghdad compound where Sergeant Maseth died.

But in a sworn statement, apparently prepared for an investigation of Sergeant Maseth’s death by the Army’s Criminal Investigative Division, a Pentagon contracting official described how both military and KBR officials were aware of the growing danger from poor electrical work.

In the statement, Ingrid Harrison, an official with the Pentagon’s contracting management agency, disclosed that an electrical fire caused by poor wiring in a nearby building two weeks before Sergeant Maseth’s death had endangered two other soldiers.

“The soldiers were lucky because the one window that they could reach did not have bars on it, or there could have been two other fatalities,” Ms. Harrison said in the statement. She said that after Sergeant Maseth died, a more senior Pentagon contracting official in Baghdad denied knowing about the fire, but she asserted that “it was thoroughly discussed” during internal meetings.