But what became particularly important after Katrina was ensuring that the company has multiple ways to contact employees. Standard means of contact, such as addresses and phone numbers, weren't enough "after people evacuated to the four corners of the country," Serio said.

He added that Office Depot now also asks employees to provide contact information for their spouses or partners, plus home e-mail addresses, BlackBerry PINs, the name of an out-of-state relative and details on whether their cell phones accept text messages.

F.A. Richard & Associates Inc., an insurance services firm in Mandeville, La., was hit by three hurricanes last year: Katrina, followed by Rita, which affected its Lafayette, La., and Houston offices, and Wilma, which knocked out power at its Boca Raton, Fla., office for two weeks. Consequently, FARA doesn't just have a Plan B for this year -- it also has a Plan C, said David Casse, its IT and telecommunications manager.

For example, the company has documented what each of its workers does and made plans for how the functions could be performed if individual employees weren't available during an emergency, Casse said. Similarly, FARA has audited all of its computers and documented the tasks they handle, whether the work could be re-created and whether the systems needed to be backed up, mirrored or made redundant.

Mike Clark, systems manager at Unibill Inc. in Lake Charles, La., thought the billing services provider was well protected last year. Unibill is headquartered in an old bank building that is located on high ground and capable of withstanding just about anything, Clark said.