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EXHIBIT 10.3

                                 TRANCHE B NOTE

  $43,125,000                                                    Cleveland, Ohio
                                                          As of January 24, 2000

         FOR VALUE RECEIVED, the undersigned, STERIS CORPORATION, an Ohio
  corporation ("Borrower"), promises to pay on the last day of the Commitment
  Period, as defined in the Credit Agreement (as hereinafter defined), to the
  order of KEYBANK NATIONAL ASSOCIATION ("Bank") at the Main Office of KEYBANK
  NATIONAL ASSOCIATION, as Agent, 127 Public Square, Cleveland, Ohio 44114-1306
  the principal sum of

   FORTY-THREE MILLION ONE HUNDRED TWENTY-FIVE
   THOUSAND AND 00/100................................................   DOLLARS

  or the aggregate unpaid principal amount of all Tranche B Loans made by Bank
  to Borrower pursuant to Section 2.1B of the Credit Agreement, whichever is
  less, in lawful money of the United States of America. As used herein,"Credit
  Agreement" means the Credit Agreement dated as of January 26, 1999, among
  Borrower, the banks named therein and KeyBank National Association, as Agent,
  as amended and as the same may from time to time be further amended, restated
  or otherwise modified. Capitalized terms used herein shall have the meanings
  ascribed to them in the Credit Agreement.

         Borrower also promises to pay interest on the unpaid principal amount
  of each Tranche B Loan from time to time outstanding, from the date of such
  Tranche B Loan until the payment in full thereof, at the rates per annum which
  shall be determined in accordance with the provisions of Section 2.1B of the
  Credit Agreement. Such interest shall be payable on each date provided for in
  such Section 2.1B; provided, however, that interest on any principal portion
  which is not paid when due shall be payable on demand.

         The portions of the principal sum hereof from time to time representing
  Prime Rate Loans and LIBOR Loans, and payments of principal of any thereof,
  shall be shown on the records of Bank by such method as Bank may generally
  employ; provided, however, that failure to make any such entry shall in no way
  detract from Borrower's obligations under this Note.

         If this Note shall not be paid at maturity, whether such maturity
  occurs by reason of lapse of time or by operation of any provision for
  acceleration of maturity contained in the Credit Agreement, the principal
  hereof and the unpaid interest thereon shall bear interest, until paid, at a
  rate per annum equal to the Default Rate. All payments of principal of and
  interest on this Note shall be made in immediately available funds.

         This Note is one of the Tranche B Notes referred to in the Credit
  Agreement. Reference is made to the Credit Agreement for a description of the
  right of the undersigned to anticipate payments hereof, the right of the
  holder hereof to declare this Note due prior to its stated maturity, and other
  terms and conditions upon which this Note is issued.

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         Except as expressly provided in the Credit Agreement, Borrower
  expressly waives presentment, demand, protest and notice of any kind.

         JURY TRIAL WAIVER. BORROWER, AGENT AND EACH OF THE BANKS WAIVE ANY
  RIGHT TO HAVE A JURY PARTICIPATE IN RESOLVING ANY DISPUTE, WHETHER SOUNDING IN
  CONTRACT, TORT OR OTHERWISE, AMONG BORROWER, AGENT AND THE BANKS, OR ANY
  THEREOF, ARISING OUT OF, IN CONNECTION WITH, RELATED TO, OR INCIDENTAL TO THE
  RELATIONSHIP ESTABLISHED AMONG THEM IN CONNECTION WITH THIS NOTE OR ANY OTHER
  NOTE OR OTHER INSTRUMENT, DOCUMENT OR AGREEMENT EXECUTED OR DELIVERED IN
  CONNECTION HEREWITH OR THE TRANSACTIONS RELATED THERETO.

                                   STERIS CORPORATION

                                   By: /s/ Bill R. Sanford
                                        ----------------------------------------
                                           Bill R. Sanford, Chairman of the
                                           Board, President, and Chief
                                           Executive Officer

                                   and: /s/ Les C. Vinney
                                        ----------------------------------------
                                            Les C. Vinney, Senior Vice President
                                            Finance and Operations, and Chief
                                            Financial Officer


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