VENTURA, Calif. (AP) _ A judge has ruled that an oil company could have prevented the deaths of three young workers who were overwhelmed by poisonous gases at a production site.

Vintage Petroleum was negligent in assessing the geological risks at its Seacliff site in 1994, Ventura County Superior Court Judge Barbara Lane said in the ruling released Wednesday.

Ron Johnson, 24, Jason Hoskins, 22, and Sean Harris, 26, were killed by poisonous gases that spouted from an open pipe.

Their survivors sued Tulsa, Okla.-based Vintage Petroleum for economic losses and pain and suffering, and were seeking damages between $10 million and $20 million, attorneys said. The damages phase of the trial began after Lane's ruling.