As Monday night's fatal shootings at a business meeting in the Navy Yard show, violence stalks the workplace.

Since 1993, about 300 workers in the Philadelphia area have been slain on the job, according to figures from the Bureau of Labor Statistics.

In 2005, the latest year for which figures are available, the region's 15 homicides were the second-biggest reason for workplace deaths after construction accidents, or "falling." There were 16 falling deaths and 12 road-related deaths in 2005, the government says. There were 76 total workplace fatalities.

In many years, though, homicides held top billing as the main reason employees did not come home in the Philadelphia region. The deaths ranged from a high of 42 in 1993 to nine in 2002 in the region.

It is a concern among businesses in the city, which has seen a spike in violence. Just this week, a group of Port Richmond industrial companies installed high-resolution cameras in the neighborhood to help catch muggers and others who threaten employees coming or going to work, as well as garbage dumpers.

The cameras feed video to the local police station and can be accessed by police computers in cruisers.

Tom Cerchiaro, vice president of operations at Active Radiator, of Port Richmond, said one employee was shot in the leg last fall walking home about five blocks from the company. "This is a hub of activity, and we want to keep it safe," he said yesterday. The company has 168 employees in Philadelphia.

Other companies protect themselves with internal security. Cardone Industries Inc., the large auto-parts rebuilder, employs 30 to 40 security guards - which is bigger than the police forces in many Pennsylvania towns - to protect several factories throughout the city. The company has more than 4,000 workers in Philadelphia.

Across the nation, 564 workers were victims of homicide on the time clock in 2005.

New York and Los Angeles had the most among metropolitan regions, with 30 each. They were followed by Atlanta with 23, Chicago with 19, and Washington with 16. Houston had 15.

Chris McGoey, president of McGoey Security Consulting, of Los Angeles, which specializes in workplace violence, said the vast majority of workplace homicides are clerks in late-night convenience stores or restaurants.

Factories are common sites of homicides, many times because of spouses or relatives working in the same place and stress building in the relationship, McGoey said.

In other cases, a worker, colleague, friend or relative harbors a resentment against a person and knows where to find him or her - at work. Lawyers and stockbrokers can be easy targets, too, he said.

At the Navy Yard Monday night, police said, Vincent Dortch, 44, of Newark, Del., shot and killed Mark Norris, 46, of Pilesgrove, N.J.; Robert Norris, 41, of Newark, Del.; and James Reif, 42, of Endicott, N.Y.

Dortch, who apparently believed he had been defrauded by the others, then killed himself, police said. A fifth man, identified as Patrick Sweeney of Maple Shade, also was shot by Dortch, police said, and was hospitalized yesterday.

The perception is that "people just snap," McGoey said. But "you look back and there is a trail," he said. They might have made threats by phone or been acting irregularly.

Workplace homicides rise and fall with demographics, the economy and the popularity of certain drugs. McGoey said there were spikes in workplace homicides in the early 1980s and the early 1990s. As for now, "we are definitely a more tightly woven society. We are so stoked on caffeine," he said.

It is difficult to crack down on security in a nation that loves freedom. "You know how much people hate airports," McGoey said. Imagine such security at malls or office buildings.

The Occupational Safety & Health Administration, which is part of the Labor Department, investigates workplace fatalities. But it rarely investigates homicides, which are handled by local police.

Companies have to provide employees with a safe working environment, according to government regulations. But "there is no national standard that deals with workplace violence," OSHA spokeswoman Lenore Uddyback-Fortson said yesterday.

Contact staff writer Bob Fernandez at 215-854-5897 or bob.fernandez@phillynews.com.