Hurricane Gustav may cause insurance claims as high as $10 billion, including damage to oil facilities, according to risk-management companies that issued preliminary estimates a day after the storm hit Louisiana. While Gustav was significantly weaker than 2005's Hurricane Katrina, which cost insurers $41 billion, oil workers, utility crews, fishermen, and other business owners spread across the Gulf coast Tuesday to assess the damage. “We will be addressing our hardest-hit policyholders first,” said Elizabeth Stelzer, spokeswoman for Nationwide Mutual Insurance Company. “Those homes with a tree through a wall, an exposed roof, or other claims in which the home has become uninhabitable are the priority.” Power outages from the storm continued to grow Tuesday, with utility Entergy Corporation saying it has the second-largest number of outages in the company's nearly 100-year history, trailing only the devastation of Katrina. Losses on land were expected to total between $3 billion and $7 billion, and oil-drilling damage at about $1 billion to $3 billion, Risk Management Solutions Incorporated estimated. Catastrophe risk-modeling company AIR Worldwide Corporation put preliminary losses on land between $2 billion and $4.5 billion. Katrina was the biggest natural disaster loss in the history of the insurance industry. Insurers paid $41 billion arising from 1.7 million claims for damage to homes, businesses, and vehicles to policy holders in six states. Florida's Hurricane Andrew—the previous record holder—produced $15.5 billion in losses in 1992.