The control center that oversees the Metro rail system is too small, understaffed and inadequately equipped, according to preliminary findings by a consulting firm.

Boeing Aerospace Co., which was hired by Metro to conduct a $225,000 study of the transit authority's safety procedures, recommended improvements in the control center along with a series of other changes in safety rules and equipment.

The study stemmed from a January 1982 derailment in which three persons died.

A Metro spokesman said yesterday that the transit agency already has taken steps to carry out some of the consultants' recommendations and is studying other measures.

"There is not a life-threatening safety problem on the Metro system," said Beverly R. Silverberg, Metro's public affairs director.

Carlton R. Sickles, chairman of a safety committee established by Metro's board of directors, said the study was aimed at providing an "independent look" at Metro's safety procedures.

He cautioned that the consultants' findings have not yet been thoroughly analyzed by Metro officials. "It is preliminary, as far as I'm concerned," he said.

The consultants' report has not yet been made public. A brief summary of findings and recommendations was prepared for a safety committee meeting last month and made public by Metro.

The summary noted that Metro officials are considering changes in the control center, including possible installation of a new computer, at a cost estimated at $25 million to $30 million.

Among steps the transit authority has taken to improve safety, according to the summary, are establishment of a new training program for Metro employes at a yearly cost of $200,000 to $500,000 and a change in evacuation procedures.

Under the new plan, emergency handles will be installed in subway cars to allow passengers to escape more easily if there is a fire, dense smoke or other hazard.