An Alexandria judge yesterday ordered a Fairfax firm that designs exhibits to refrain temporarily from using the trade secrets or customer lists of a competing Alexandria firm and from hiring more of its employes.

Circuit Court Judge Donald H. Kent issued the temporary restraining order against the Creative Dimensions Group a day after the Alexandria firm Design & Production Inc. filed a $5 million civil suit against the Fairfax company and two of its employes.

Design & Production is one of the Washington area's largest graphic communications firms and specializes in building exhibits for museums, theaters and restaurants. One of its best-known projects is the Colonial Williamsburg Visitors Center.

In the lawsuit, filed in Alexandria Circuit Court, Design & Production charges Creative Dimensions with willfully and maliciously attempting to do "irreparable harm" to the Alexandria firm by using its design techniques and a customer list that one of its former board members allegedly leaked to the company.

The former board member, Kelly W. Wright Jr., was hired March 4 as the vice president of Creative Dimensions, according to the lawsuit. It charges that Wright furnished his new employer with design and fabric techniques, trade secrets and existing and potential customers of the Alexandria firm.

All this, the firm charges in the court records, is in violation of Wright's contract with Design & Production, which states that Wright cannot seek employment "within 150 miles of the Washington Monument" for two years after terminating his employment with the company.

Officials of the Fairfax firm could not be reached for comment.