With Hurricane Irene comes a reminder that the unexpected happens, and yet more than half of small businesses say they don't have a disaster preparedness plan for their business data, says a new survey.

This lack of readiness is even though small business owners ranked the permanent loss of data as the top challenge to maintain their business if a natural disaster were to strike, says a poll conducted by Carbonite, an online backup system provider.

Four out of five (81 percent) said data was their organization's most valuable asset, and that losing it would be more devastating than losing the physical location or products and materials.

Why are small firms so ill-prepared? Fifty-nine percent of the 130 owners surveyed said they had no disaster plan because they "haven't thought about it." Just 13 percent think a natural disaster actually could happen to them, and more than half (54 percent) said data Armageddon was unlikely to impact their business. Yet more than two-thirds (69 percent) acknowledged they would lose money if their business were unable to function for a single day. And a fifth of those surveyed in August cited cost, saying they don't have the money to plan or that the cost of planning was too unpredictable.

Peter Lamson, Carbonite's senior vice president and general manager of small business, pointed to FEMA figures that 40 to 60 percent of small businesses never re-open after a data disaster.

The figures suggest "that small business owners need to pay attention to the risk and to prepare accordingly," said Lamson. "

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