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EXHIBIT 15.1 LETTER RE: UNAUDITED INTERIM FINANCIAL INFORMATION
Board of Directors and Shareholders
STERIS Corporation
We are aware of the incorporation by reference in the following Registration
Statements and related Prospectuses of our report dated July 17, 2000, relating
to the unaudited consolidated interim financial statements of STERIS Corporation
and Subsidiaries that are included in its Form 10-Q for the quarter ended June
30, 2000:
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Registration
Number Description Filing Date
------------ ---------------------------------------------------------- -----------------
<C> <S> <C>
333-40082 Form S-8 Registration Statement --Nonqualified Stock June 26, 2000
Option Agreement between STERIS Corporation and Laurie
Brlas and the Nonqualified Stock Option Agreement
between STERIS Corporation and David L. Crandall
333-40058 Form S-8 Registration Statement --Nonqualified Stock June 23, 2000
Option Agreement between STERIS Corporation and
Les C. Vinney
333-65155 Form S-8 Registration Statement -- STERIS Corporation October 1, 1998
Long Term Incentive Stock Plan
333-55839 Form S-8 Registration Statement -- Nonqualified Stock June 2, 1998
Option Agreement between STERIS Corporation and John
Masefield and the Nonqualified Stock Option Agreement
between STERIS Corporation and Thomas J. DeAngelo
333-32005 Form S-8 Registration Statement -- STERIS Corporation July 24, 1997
1997 Stock Option Plan
333-06529 Form S-3 Registration Statement -- STERIS Corporation June 21, 1996
333-01610 Post-effective Amendment to Form S-4 on Form S-8 -- May 16, 1996
STERIS Corporation
33-91444 Form S-8 Registration Statement -- STERIS Corporation April 24, 1995
1994 Equity Compensation Plan
33-91442 Form S-8 Registration Statement -- STERIS Corporation April 24, 1995
1994 Nonemployee Directors Equity Compensation Plan
33-55976 Form S-8 Registration Statement -- STERIS Corporation December 21, 1992
401(k)Plan
33-55258 Form S-8 Registration Statement -- STERIS Corporation December 4, 1992
Amended and Restated Non-Qualified Stock Option Plan
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/s/ Ernst & Young LLP
Cleveland, Ohio
August 10, 2000
