Life mocked art at the U.S. Bureau of Engraving and Printing early yesterday morning when a ceiling caught fire in the very room where presses were churning out stamps honoring the nation's fire departments.

The fire at the bureau's annex at 14th and C streets SW caused an estimated $75,000 in damage to the four presses used in making the stamps featuring a 19th century fire wagon. Night shift employes who were making the stamps were evacuated, and no injuries were reported.

Fire officials said the blaze apparently started in heat ducts located above the presses. Duct materials, as well as accumulations of ink and dust, ignited when a cooling system malfunctioned and the ducts overheated. The fire spread to ceiling tiles and the presses.

Burning ink created acrid smoke, forcing firefighters to wear gas masks. So thick was the smoke, they said, that they originally were unable to find the source of the fire. When they attempted to ventilate the 4,000 square-foot area, they found that the windows were welded shut.

A bureau spokesman said yesterday that the fire was contained by automatic sprinkling devices until the fire department could arrive. Two of the presses were slightly damaged and will be operating again next week, he said, but two other presses will require more extensive repair. He said the postal printing operation will not be seriously affected.