Exhibit 23.1 CONSENT OF INDEPENDENT AUDITORS We consent to the use of our report dated July 25, 2002, with respect to the financial statements of EG&G Technical Services, Inc. and Subsidiary included in this Form 8-K/A and incorporated by reference in the Registration Statements (Forms S-8 No. 333-91053, 33-61230, 333-24063, 333-48791 and Form S-3 No. 333-59203). /s/ Ernst & Young LLP McLean, Virginia November 4, 2002