ST. LOUIS — Though wind damage was substantial from the storms that roared through St. Louis recently, many small-business owners are finding out that disaster recovery for business encompasses much more than clearing the front door of debris.

Businesses have responsibilities to employees, customers, suppliers and a gaggle of others who may not care that the power is out.

Whether businesses survive often depends on their preparation.

"Think about what you would do within the first 72 hours (of an emergency) if you couldn't depend on external resources," said Albert Marcella, a professor of management and information systems at Webster University. "Companies should be cognizant of how to take care of themselves in case the first responders can't get to them."

As many as 40 percent of small businesses do not reopen after major disasters such as floods, tornadoes or earthquakes, according to the Red Cross.

Marcella has been studying the effects of disasters on businesses since the mid-1980s, and is the author of "Business Continuity, Disaster Recovery and Incident Management Planning: A Resource for Ensuring Ongoing Enterprise Operations." He is president of Ballwin, Mo.-based Business Automation Consultants.

The best time to plan, he said, is when things are calm. Most companies take the initiative to plan only after they experience a problem or a near-miss.

That's what happened last summer with St. Louis-based developer THF Realty, when the company's electricity failed for a day because of a blown circuit. Marian Nunn, the chief operating officer, was among those who saw a vulnerability.

"We thought in terms of what if we can't work for a period of time, as opposed to what the cause might be," said Nunn. Not only would the firm risk losing real-estate deals, but there could be potential financial penalties for delays.

So the company set up a plan, which was tested two weeks ago.

At 6 a.m. on July 20, Nunn was contacted when employees opened the office without electricity. That set off a series of steps, starting with using a phone tree to contact the company's 100 employees and gathering teams to inspect its properties for storm damage.

THF's backup computer data was retrieved from an off-site location, and the company set up alternative office space for computer access and meetings in buildings with power.

As of last Wednesday afternoon, THF's main office was still without power. But Nunn said the disaster plan has the company operating at about 70 percent efficiency. THF even closed three deals last week.

"I never went into panic mode because I knew we had a plan in place," Nunn said.

The potential for panic is the reason such a plan is necessary, said Bob Komer, manager of loss control services for the Warren, N.J.-based Chubb Group of Insurance Companies, a $25 billion property and casualty insurer.

"For the ones that do it properly, there is a step-by-step protocol," Komer said. "That's real important because people's emotions run high and people don't think as clearly as they would in normal circumstances."

While crisis management varies for every company, insurance is a near-universal part of crisis planning.

Kathy Conley-Jones, owner of the Conley Financial Group, said business owners should start by discussing options such as business interruption insurance, which provides compensation in any event that shuts down a business and shuts off revenues. Jones also encourages insuring against wind, flood and hail damage.

She stressed the importance of keeping policies current by telling insurers about property upgrades.

"The worst thing in the world is finding out your coverage won't stand up to the loss you just sustained," Jones said.