1 EXHIBIT 16 ARTHUR ANDERSEN (Logo) Arthur Andersen LLP 8000 Towers Crescent Drive Vienna VA 22182-2725 (703) 734-7300 March 9, 1998 Office of the Chief Accountant Securities and Exchange Commission 450 Fifth Street, N.W. Washington, DC 20549 Dear Sir/Madam: We have read Item 4 included in the Form 8-K dated March 4, 1998 of Fusion Systems Corporation to be filed with the Securities and Exchange Commission and are in agreement with the statements contained therein. Very truly yours, /s/ Arthur Andersen LLP - ----------------------- ARTHUR ANDERSEN LLP tlm cc: David M. O'Loughlin, Corporate Counsel, Eaton Corporation 5