( CNN ) -- Two of the main companies involved in the disastrous 2010 Gulf of Mexico oil spill were more focused on personal injury risks than the potential for a major accident , a federal agency said in a report released Tuesday . The U.S. Chemical Safety Board , an independent federal agency entrusted with investigating serious chemical accidents , released findings from their months-long analysis Tuesday at a public hearing in Houston . The CSB said two of the main companies involved , BP and Transocean , as well as U.S. regulators , focused too heavily on personal injury issues such as dropping objects , slips , trips and falls instead of on overarching considerations of importance , such as the potential of losing control of an oil well or drilling using a complicated rig . Three lessons linger from BP oil spill . The disaster began on April 20 , 2010 , when an explosion aboard the Deepwater Horizon drilling rig killed 11 people and caused a three-month-long oil spill , sending nearly 5 million barrels of crude spewing into the Gulf . `` A number of past CSB investigations have found companies focusing on personal injury rates while virtually overlooking looming process safety issues -- like the effectiveness of barriers against hazardous releases , automatic shutoff system failures , activation of pressure relief devices , and loss of containment of liquids and gases , '' CSB Chairman Rafael Moure-Eraso said . The agency said the oil industry had not learned key lessons from a 2005 blast at a BP refinery in Texas City -- an incident it said bears an `` eerie resemblance '' to the Deepwater Horizon disaster . During that incident , a fire and explosion during startup of a unit that raises gasoline octane killed 15 people and injured 180 others . Kevin Costner wins suit filed by Stephen Baldwin over oil cleanup machine . The CSB pointed out that during both occasions , workers were being congratulated for low rates of personal injuries on the very day that the explosions occurred . `` The emphasis on personal injury and lost work-time data obscures the bigger picture : that companies need to develop indicators that give them realistic information about their potential for catastrophic accidents . How safety is measured and managed is at the very core of accident prevention , '' said CSB investigator Cheryl MacKenzie . `` If companies are not measuring safety performance effectively and using those data to continuously improve , they will likely be left in the dark about their safety risks . '' The Minerals Management Service ( MMS ) , the now-defunct agency under the Department of the Interior that oversaw offshore oil exploration and production during the time of the 2010 accident , had already given BP and Transocean a total of 15 safety awards , and BP was a finalist for yet another . But CSB investigators found that the deciding factors used to determine recipients were based on personal safety records and not on safety management programs designed to prevent serious disasters . Ex-BP engineer says company records clear him in Gulf spill . The Interior Department subsequently dismantled the MMS and formed the Bureau of Safety and Environmental Enforcement ( BSEE ) . Besides concluding that Transocean and BP had `` multiple safety management system deficiencies that contributed '' to the oil spill , the CSB also found the federal government should adopt some changes with its policies . In Tuesday 's report , the agency concluded the Interior Department still needs to develop a better safety indicator program for reporting potential precursors to major incidents instead of just reporting accidents . The CSB is a Washington-based independent federal agency charged with investigating industrial chemical accidents . Board members are appointed by the president and confirmed by the U.S. Senate . In April , BP announced that it had reached an estimated at $ 7.8 billion settlement with thousands of businesses and individuals who filed damage claims in the wake of the spill . Independent scientists have said the spill harmed marine life and bird populations as well as coral reefs in the Gulf . Other researchers said they have found at least one plume of hydrocarbons from the well deep below the surface . Alaska drilling : From 'hell no ! ' to ... 'OK '
Report : Interior Department , Transocean , regulators focused too heavily on personal injury issues . Past investigations saw companies `` virtually overlooking looming process safety issues '' thousands people died and nearly 5 million barrels of oil spilled in the three-month Gulf of Mexico disaster . Report : BP needs to a better job of reporting major accident risks .