Hurricane Irene: Refineries Prepare to Shut Down [MAPS AND PHOTOS]

Hurricane Irene has left the Bahamas and is now churning toward the East Coast of the United States.

Irene's destructive force has battered southeastern islands of the Bahamas, leaving structural damage, blocked roads and power outages.

The storm could force East Coast refineries, concentrated in New Jersey and Pennsylvania, to close down as a precaution.

Some refineries were already starting to turn off equipment and batten down, the Washington Post reported Thursday.

Their main buildings are designed to withstand hurricane-force winds and earthquakes, but some of their pipes, cooling towers and power lines are susceptible to wind damage, according to the Post, which adds that the utilities are expecting widespread power outages from winds and downed trees.

It could take several days for a refinery to resume operating after a shutdown, with many needing almost a month to get back to full operation.

Even if the storm eventually misses them, they can't take chances, Ben Brockwell at the Oil Price Information Service, which monitors fuel shipments around the country, told the Post.

New York and New Jersey are among five states that have issued a state of emergency ahead of what could be the worst hurricane to hit them in centuries. The storm is expected to bring at least five to 10 inches of rain, major flooding and winds of up to 100 mph, when it reaches New Jersey on Saturday afternoon, said Bill Read, director of the National Hurricane Center.

Refinery operators must decide some 72 hours before a hurricane hits whether to go into what is called cold shutdown, the Post reported.

Jeff Hazel, senior director for refining technology at the National Petrochemical & Refiners Association, told the Post refiners are most concerned about losing power due to high winds. Refineries normally generate some power on site, but they rely mainly on outside power sources.