For years, whenever a disaster struck, Rick Johnson and David Kleber would volunteer their expertise as longtime amateur radio operators to keep the lines of communication open.

When Hurricane Katrina ravaged parts of Louisiana and Mississippi last month, the ham operators pitched in to help again, but this time their hobby had become a business, RemComm Inc.

"It was a spectacular success," said Mr. Johnson, a retired lawyer. Mr. Kleber is a sales and marketing veteran who most recently sold telecommunications for Verizon Wireless.

The Highland Park-based company's product is designed to fill the communications void when power systems have been knocked out and emergency workers' cell phones and computers aren't working.

RemComm's software allows emergency workers to record critical information from a disaster scene on battery-operated laptop computers and transmit it via advanced radio to emergency centers.

The week after Katrina hit, four RemComm workers and three volunteers traveled to the Gulf Coast to help the Salvation Army track mobile canteens that were distributing hot meals to hurricane victims.

The canteens, located in Louisiana, had been without phone lines or electronic links for several days, "So we provided data on meals, supplies and what needed to be resupplied," said Mr. Johnson. It coordinated its efforts with the Mississippi Emergency Management Agency and the American Red Cross in Jackson, Miss.

RemComm has 10 employees, two of whom are full time. The company is funding operations through a combination of the co-founders' money and some private outside investment.

It has sold its systems to O'Hara's emergency management agency and is "bartering and volunteering our services to get the product out" to other potential users, Mr. Johnson said.

Its systems have been utilized for community activities, such as the Head of the Ohio crew competition this month and the Senior Olympics in June.

Though their company provided services to the Katrina effort on a volunteer basis, Mr. Johnson is confident RemComm can sell its services by meeting a specialized demand in the growing market for first-response and homeland security technology.

"Following 9/11, it crystallized for us the need to form a company."

Among other local companies that already have captured a share of post-9/11 homeland security business:

MSA: The safety products manufacturer based in O'Hara, makes gas masks used by the military; safety helmets used by workers at the World Trade Center disaster site in Manhattan; respirators; and thermal imaging cameras. Besides the military, its customers include security personnel and firefighters.

Draeger Safety: The Findlay-based company makes gas masks, self-contained breathing units for firefighters and special diving equipment used by the U.S. military.

Kuchera Defense Systems: The Windber, Somerset County, company has developed robots, sensors, cameras and other devices used by the military and defense contractors.

NABCO Inc.: Located in Canonsburg, it makes containers that hold bombs and other explosives. Its customers include the Army, Navy, Air Force, FBI, Secret Service, U.S. Capitol Police, state and local bomb squads, and international security agencies.