Local federal agencies scattered in more than 1,000 sites ranging from the White House to an underground bunker in Olney and a hollowed-out mountain in Virginia have tightened security in anticipation of terrorism triggered by the war in the gulf.

Workers seem to be taking the security measures in stride despite a rash of bomb threats and rumors (none true, so far) that bombs have been found and the short-lived report yesterday that masked men with submachine guns had taken over two floors of a leased building in Rosslyn.

The General Services Administration handles security for 206 buildings in Washington (112 of them leased), 107 in suburban Maryland (80 leased) and 191 in Virginia (165 leased). Those totals don't include hundreds of military facilities or sprawling operations such as the Agricultural Research Center, the National Institutes of Health, the Bureau of Engraving and Printing, NASA's Goddard Space Flight Center, the U.S. Capitol, Treasury Department, the museums, the U.S. Soldiers' and Airmen's Home, veterans hospitals or hundreds of postal buildings and facilities.

Most attention is on high-profile buildings such as the White House, Capitol and Pentagon. But security is a fact of life in most places. Spot checks indicate that workers and visitors are coping with the new rules. Because of ID checks and sign-in rules, many employees are learning to arrive earlier than usual.

At the Office of Personnel Management, for example, guards are checking employee IDs and questioning visitors for the first time in memory. Car pools that use underground parking lots must display vehicle IDs, and each passenger must show a government ID before being admitted. Briefcases and bags are searched routinely at most buildings, and some regular tours have been canceled.

A one-page security briefing posted on the doors of the Federal Communications Commission advises that lawyers "filing documents late in the day should allow additional time for signing in."

Whether your work for the federal government or plan to visit a federal building for business or pleasure, be prepared to wait, to have your belongings searched and not have anything outrageous in your briefcase.Can't Take It With You

Thanks to higher federal pay scales and the tax-deferred investment plan, many employees will accumulate large estates that can be eaten up by taxes when they die.

Under the thrift savings plan, workers who invest early, and wisely, could have $800,000 or more in their retirement accounts. Some area federal workers are sitting on valuable real estate or have substantial insurance policies. Tomorrow at noon on radio station WNTR (1050 AM), lawyers Virginia Hurt Johnson, Thomas J. O'Rourke and G. Jerry Shaw will talk about estate planning for workers and retirees.Job Fair

Representatives of 50 federal agencies will be at the Washington Convention Center Wednesday and Thursday interviewing candidates for secretarial-clerical jobs. The session is sponsored by the Office of Personnel Management. There will be on-site job tests. Call 703-538-2233.