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EXHIBIT 10.18

                           CHANGE OF CONTROL AGREEMENT


THIS CHANGE OF CONTROL AGREEMENT ("Agreement") is made as of the 18th day of
March, 2000, between STERIS Corporation, an Ohio corporation ("STERIS"), and LES
C. VINNEY ("Executive"), and supercedes the prior such change of control
agreement dated July 16, 1999.

STERIS is entering into this Agreement in recognition of the importance of
Executive's services to the continuity of management of STERIS and based upon
its determination that it will be in the best interests of STERIS to encourage
Executive's continued attention and dedication to Executive's duties in the
potentially disruptive circumstances of a possible Change of Control of STERIS.
(As used in this Agreement, the term "Change of Control" and certain other
capitalized terms have the meanings ascribed to them in Section 7, at the end of
this Agreement.)

STERIS and Executive agree, effective as of the date first set forth above (the
"Effective Date"), as follows:

1.   Basic Severance Benefits. The benefits described in the subsections of this
Section 1 are subject to the limitations set forth in Subsections 4.1 (regarding
withholding) and 4.2 (requiring the execution of a waiver and release by
Executive).

     1.1 Lump Sum Severance Benefit if Employment is Terminated in Certain
Circumstances Within Two Years of a Change of Control. If, within two years
following the occurrence of a Change of Control, Executive's employment with
STERIS is terminated

     (a) by STERIS for any reason other than Cause, Disability, or death,

     (b) by Executive after a Reduction of Compensation or a Mandatory
     Relocation has occurred, or

     (c) by Executive following a determination in good faith by Executive that
     as a result of a Change of Control he is unable to carry out the
     authorities, power, functions, responsibilities, or duties that he had in
     the positions and offices of STERIS held by Executive before the Change of
     Control in the same manner, with the same discretion, and to the same
     extent as he was able to carry out the authorities, powers, functions,
     responsibilities, or duties attached to those positions as in effect before
     the Change of Control.

STERIS shall pay to Executive, within 30 days after the Termination Date, a
lump sum severance benefit equal to three times the sum of

     (x) one year's Base Salary (at the highest rate in effect at any time
     during the one year period ending on the date of the Change of Control),
     plus

     (y) Executive's Average Annual Incentive Compensation.

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     1.2 Accrued Base Salary and Vacation Pay. If Executive becomes entitled to
payment of a lump sum severance benefit under Subsection 1.1 above, STERIS
shall, within 10 days after the Termination Date, pay to Executive (a) all Base
Salary accrued through the Termination Date but not previously paid and (b) a
cash payment equal to the value of any vacation time accrued through the
Termination Date but not used by Executive (valued at a rate equal to
Executive's Base Salary at the highest rate in effect at any time during the one
year period ending on the date of the Change of Control).

     1.3 Special Prior Year MICP Payments. If Executive becomes entitled to
payment of a lump sum severance benefit under Subsection 1.1 above and the
Termination Date occurs on the last day of or after the end of a Fiscal Year but
before STERIS makes final MICP payments with respect to that Fiscal Year, STERIS
shall pay to Executive, at the regularly scheduled time for such final MICP
payments (the "Regular Payment Date"), but in any event not later than 60 days
after the end of the Fiscal Year, as incentive compensation, the same amount or
amounts that STERIS would have paid to Executive as incentive compensation with
respect to that Fiscal Year at the Regular Payment Date if Executive's
employment had continued through the Regular Payment Date. This Subsection 1.4
is intended to override any provision of the MICP that would otherwise cause
Executive to forfeit any incentive compensation with respect to any Fiscal Year
that ends on or before the Termination Date because Executive does not remain in
the employ of STERIS through the Regular Payment Date with respect to that
Fiscal Year.

     1.4 Special Pro-Rata MICP Payment. If Executive becomes entitled to payment
of a lump sum severance benefit under Subsection 1.1 above and the Termination
Date occurs on other than the last day of a Fiscal Year, in addition to the
payment, if any, provided for in Subsection 1.3 above, STERIS shall, within 60
days after the end of the calendar quarter in which the Termination Date occurs,
pay to Executive, as additional incentive compensation for the period from the
first day of the Fiscal Year in which the Termination Date occurs through the
Termination Date (the "Pre-Termination Part Year"), an amount equal to the
excess of:

     (a) the product of the fraction specified in the last sentence of this
     Subsection 1.4 and the higher of (i) Executive's Target Annual Incentive
     Compensation and (ii) the dollar amount of the cumulative award that would
     have been payable to Executive under the MICP for that entire Fiscal Year
     had the level of relevant performance through the end of the Fiscal Year
     equaled the level of relevant performance through the last calendar
     quarter, if any, in that Fiscal Year that ended before the Termination
     Date, over

     (b) the amount of incentive compensation previously paid to Executive with
     respect to that Fiscal Year.

The fraction to be used in calculating the amount to be paid under this
Subsection 1.4 shall have a numerator equal to the number of days in the
Pre-Termination Part Year and a denominator of 365.

     1.5 Continued Health, Dental, and Lift Insurance Coverage. If Executive
becomes entitled to payment of a lump sump severance benefit under Subsection
1.1 above, STERIS shall, during the period from the Termination Date through the
third anniversary of the Termination Date, continue to provide Executive with
the same health, dental, and life insurance coverage and benefits that were
being provided to Executive immediately before the Change of Control. If

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Executive becomes entitled to payment of a lump sum severance benefit under
Subsection 1.2 above, STERIS shall, during the period from the Termination Date
through the second anniversary of the Termination Date, continue to provide
Executive with the same health. dental, and life insurance coverage and benefits
that were being provided to Executive immediately before the Change of Control.
Coverage and benefits to be provided under this Subsection 1.5 shall be provided
to Executive at the same cost, if any, to Executive as they were provided to
Executive immediately before the Change of Control.

2.   Other Benefits.

     2.1  Reimbursement of Certain Expenses After a Change of Control.

     (a) From and after a Change of Control, STERIS shall pay, as incurred, all
     expenses of Executive, including the reasonable fees of counsel engaged by
     Executive, of defending any action brought to have this agreement declared
     invalid or unenforceable.

     (b) From and after a Change of Control, STERIS shall pay, as incurred, all
     expenses of Executive, including the reasonable fees of counsel engaged by
     Executive, of prosecuting any action to compel STERIS to comply with the
     terms of this Agreement upon receipt from Executive of an undertaking to
     repay STERIS for such expenses if, and only if, it is ultimately determined
     by a court of competent jurisdiction that Executive had no reasonable
     grounds for bringing that action (which determination need not be made
     simply because Executive fails to succeed in the action).

     (c) From and after a Change of Control, expenses (including attorney's
     fees) incurred by Executive in defending any action, suit, or proceeding
     commenced or threatened (whether before or after the Change of Control)
     against Executive for any action or failure to act as an employee, officer,
     or director of STERIS or any Subsidiary shall be paid by STERIS, as they
     are incurred, in advance of final disposition of the action suit, or
     proceeding upon receipt of an undertaking by or on behalf of Executive in
     which Executive agrees to reasonably cooperate with STERIS or the
     Subsidiary, as the case may be, concerning the action, suit, or proceeding
     and (i) if the action, suit, or proceeding is commenced or threatened
     against Executive for any action or failure to act as a director, to repay
     the amount if it is proved by clear and convincing evidence in a court of
     competent jurisdiction that Executive's action or failure to act involved
     an act or omission undertaken with deliberate intent to cause injury to
     STERIS or a Subsidiary or undertaken with reckless disregard for the best
     interests of STERIS or a Subsidiary, or (ii) if the action, suit, or
     proceeding is commenced or threatened against Executive for any action or
     failure to act as an officer or employee, to repay the amount if it is
     ultimately determined that Executive is not entitled to be indemnified.

     2.2 Indemnification. From and after a Change of Control, STERIS shall
indemnify Executive, to the full extent permitted or authorized by the Ohio
General Corporation Law as it may from time to time be amended, if Executive is
(whether before or after the Change of Control) made or threatened to be made a
party to any threatened, pending, or completed action, suit, or proceeding,
whether civil, criminal, administrative, or investigative, by reason of the fact
that Executive is or was a director, officer, or employee of STERIS or any
subsidiary, or is or was serving at the request of STERIS or any subsidiary as a
director, trustee, officer, or

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employee of a corporation, partnership, joint venture, trust, or other
enterprise. The indemnification provided by this Subsection 2.2 shall not be
deemed exclusive of any other rights to which Executive may be entitled under
the articles of incorporation or the regulations of STERIS or of any Subsidiary,
or any agreement, vote of shareholders or disinterested directors, or otherwise,
both as to action in Executive's official capacity and as to action in another
capacity while holding such office, and shall continue as to Executive after
Executive has ceased to be a director, trustee, officer, or employee and shall
inure to the benefit of the heirs, executors. and administrators of Executive.

     2.3 Disability. If, after a Change of Control and prior to the Termination
Date. Executive is unable to perform services for STERIS for any period by
reason of disability. STERIS will pay and provide to Executive all compensation
and benefits to which Executive would have been entitled had Executive continued
to be actively employed by STERIS through the earliest of the following dates:
(a) the first date on which Executive is no longer so disabled to such an extent
that Executive is unable to perform services for STERIS, (b) the date on which
Executive becomes eligible for payment of long term disability benefits under a
long term disability plan generally applicable to executives of STERIS, (c) the
date on which STERIS has paid and provided 24 months of compensation and
benefits to Executive during Executive's disability, or (d) the date of
Executive's death.

     2.4 Gross-Up of Payments Deemed to be Excess Parachute Payments.

     (a) STERIS and Executive acknowledge that, following a Change of Control,
     one or more payments or distributions to be made by STERIS to or for the
     benefit of Executive (whether paid or payable or distributed or
     distributable pursuant to the terms of this Agreement, under some other
     plan, agreement, or arrangement, or otherwise, and including, without
     limitation, any income recognized by Executive upon exercise of an option
     granted by STERIS to acquire Common Shares issued by STERIS) (a "Payment")
     may be determined to be an "excess parachute payment" that is not
     deductible by STERIS for federal income tax purposes and with respect to
     which Executive will be subject to an excise tax because of Sections 280G
     and 4999, respectively, of the Internal Revenue Code (hereinafter referred
     to respectively as "Section 280G" and "Section 4999"). If Executive's
     employment is terminated after a Change of Control occurs, the Accounting
     Firm, which, subject to any inconsistent position asserted by the Internal
     Revenue Service, shall make all determinations required to be made under
     this Subsection 2.4, shall determine whether any Payment would be an excess
     parachute payment and shall communicate its determination, together with
     detailed supporting calculations, to STERIS and to Executive within 30 days
     after the Termination Date or such earlier time as is requested by STERIS.
     STERIS and Executive shall cooperate with each other and the accounting
     Firm and shall provide necessary information so that the Accounting Firm
     may make all such determinations. STERIS shall pay all of the fees of the
     Accounting Firm for services performed by the Accounting Firm as
     contemplated in this Subsection 2.4.

     (b) If the Accounting Firm determines that any Payment gives rise, directly
     or indirectly, to liability on the part of Executive for excise tax under
     Section 4999 (and/or any penalties and/or interest with respect to any such
     excise tax), STERIS shall make additional cash payments to Executive, from
     time to time and at the same time as any

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     Payment constituting an excess parachute payment is paid or provided to
     Executive, in such amounts as are necessary to put Executive in the same
     position, after payment of all federal, state, and local taxes (whether
     income taxes, excise taxes under Section 4999, or otherwise, or other
     taxes) and any and all penalties and interest with respect to any such
     excise tax, as Executive would have been in after payment of all federal,
     state, and local income taxes if the Payments had not given rise to an
     excise tax under Section 4999 and no such penalties or interest had been
     imposed.

     (c) If the Internal Revenue Service determines that any Payment gives rise,
     directly or indirectly, to liability on the part of Executive for excise
     tax under Section 4999 (and/or any penalties and/or interest with respect
     to any such excise tax) in excess of the amount, if any, previously
     determined by the Accounting Firm, STERIS shall make further additional
     cash payments to Executive not later than the due date of any payment
     indicated by the Internal Revenue Service with respect to these matters, in
     such amounts as are necessary to put Executive in the same position, after
     payment of all federal, state, and local taxes (whether income taxes,
     excise taxes under Section 4999, or otherwise, or other taxes) and any and
     all penalties and interest with respect to any such excise tax, as
     Executive would have been in after payment of all federal, state, and local
     income taxes if the Payments had not given rise to an excise tax under
     Section 4999 and no such penalties or interest had been imposed.

     (d) If STERIS desires to contest any determination by the Internal Revenue
     Service with respect to the amount of excise tax under Section 4999,
     Executive shall, upon receipt from STERIS of an unconditional written
     undertaking to indemnify and hold Executive harmless (on an after tax
     basis) from any and all adverse consequences that might arise from the
     contesting of that determination, cooperate with STERIS in that contest at
     STERIS's sole expense. Nothing in this Paragraph (d) shall require
     Executive to incur any expense other than expenses with respect to which
     STERIS has paid to Executive sufficient sums so that after the payment of
     the expense by Executive and taking into account the payment by STERIS with
     respect to that expense and any and all taxes that may be imposed upon
     Executive as a result of Executive's receipt of that payment. the net
     effect is no cost to Executive. Nothing in this Paragraph (d) shall require
     Executive to extend the statute of limitations with respect to any item or
     issue in Executive's tax returns other than, exclusively, the excise tax
     under Section 4999. If, as the result of the contest of any assertion by
     the Internal Revenue Service with respect to excise tax under Section 4999,
     Executive receives a refund of a Section 4999 excise tax previously paid
     and/or any interest with respect thereto, Executive shall promptly pay to
     STERIS such amount as will leave Executive, net of the repayment and all
     tax effects, in the same position, after all taxes and interest, that he
     would have been in if the refunded excise tax had never been paid.

3. No Set-Off No Obligation to Seek Other Employment or to Otherwise Mitigate
Damages; No Effect Upon Other Plans. STERIS's obligation to make the payments
provided for in this Agreement and otherwise to perform its obligations
hereunder shall not be affected by any set-off, counterclaim, recoupment,
defense, or other claim whatsoever that STERIS or any of its Subsidiaries may
have against Executive. Executive shall not be required to mitigate damages or
the amount of any payment provided for under this Agreement by seeking other
employment or


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otherwise. Except as provided in the last sentence of this Section 3, neither
the amount of any payment provided for under this Agreement nor Executive's
right to any other benefit under this Agreement shall be reduced by any
compensation or benefits earned by Executive as the result of employment by
another employer or otherwise after the termination of Executive1s employment.
Neither the provisions of this Agreement, nor the execution of the waiver and
release referred to in Subsection 4.2 below, nor the making of any payment
provided for hereunder shall reduce any amounts otherwise payable, or in any way
diminish Executive's rights, under any incentive compensation plan, stock option
plan, retirement plan, disability or insurance plan, or other similar contract,
plan, or arrangement of STERIS, except that the payment of a pro-rata incentive
compensation benefit under Subsection 1.4 shall satisfy, to the extent of that
payment, any obligation STERIS might have to Executive for payments under the
MICP for the year in which the Termination Date occurs. STERIS's obligation to
provide continuing health, dental, and/or life insurance coverage and benefits,
as the case may be, shall be discontinued before the time otherwise specified in
Subsection 1.5 if, as, and when Executive becomes eligible to receive roughly
comparable health, dental, and/or life insurance coverage and benefits, as the
case may be, from a subsequent employer.

4.   Certain Limitations on Benefits.

     4.1 Taxes; Withholding of Taxes. Without limiting either the right of
STERIS to withhold taxes pursuant to this Subsection 4.1 or the obligation of
STERIS to make gross-up payments pursuant to Subsection 2.4, Executive shall be
responsible for all income, excise, and other taxes (federal, state, city, or
other) imposed on or incurred by Executive as a result of receiving the payments
provided in this Agreement, including, without limitation, the payments provided
under Section 1 of this Agreement. STERIS may withhold from any amounts payable
under this Agreement all federal, state, city, or other taxes as STERIS shall
determine to be required pursuant to any law or government regulation or ruling.

     4.2 Waiver and Release. STERIS may condition the payment of any amounts
otherwise due under Section 1 of this Agreement upon (a) the execution by
Executive of a waiver and release in the form attached to this Agreement as
Exhibit A, with blanks appropriately filled and, in the case of clause (e)
contained therein, completed with the number of days that STERIS determines is
required under applicable law, but in no event more than 45 days, and (b) the
observation of such waiting periods, if any, before and after execution of the
waiver and release by Executive as are required by law, such as, for example,
the waiting periods required for a waiver and release to be effective with
respect to claims under the Age Discrimination in Employment Act, provided that
STERIS delivers to Executive such a waiver and release, appropriately completed,
within seven days of the Termination Date.

5. Term of this Agreement. This Agreement shall be effective as of the Effective
Date and shall thereafter apply to any Change of Control occurring on or before
March 31, 2002. Unless this Agreement is terminated earlier pursuant to
Subsection 5.1, on March 31, 2002 and on March 31 of each succeeding year
thereafter (a "Renewal Date"), the term of this Agreement shall be automatically
extended for an additional year unless either party has given notice to the
other, at least one year in advance of that Renewal Date, that the Agreement
shall not apply to any Change of Control occurring after that Renewal Date.


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     5.1 Termination of Agreement Upon Termination of Employment Before a Change
of Control. This Agreement shall automatically terminate and cease to be of any
further effect on the first date occurring before a Change of Control on which
Executive is no longer employed by STERIS, except that, for purposes of this
Agreement, any termination of employment of Executive that is effected both (a)
during the one year period ending on the date of a Change of Control and (b) in
contemplation of a Change of Control shall be deemed to be a termination of
Executive's employment as of immediately after that Change of Control becomes
irrevocable (as provided in Subsection 7.4) and Executive shall be entitled to
payments and benefits under this Agreement as if Executive's employment had
continued through the day after the Change of Control became irrevocable and had
then been terminated.

     5.2 No Termination of Agreement During Two Year Period Beginning on Date of
a Change of Control. After a Change of Control, this Agreement may not be
terminated. However, if Executive's employment with STERIS continues for more
than two years following the occurrence of a Change of Control, then, for all
purposes of this Agreement other than Subsections 2.1 and 2.2, that particular
Change of Control shall thereafter be treated as if it never occurred.

6.   Miscellaneous.

     6.1 Successor to STERIS. STERIS shall not consolidate with or merge into
any other corporation, or transfer all or substantially all of its assets to
another corporation or other entity, unless such other corporation or other
entity shall assume this Agreement in a signed writing and deliver a copy
thereof to Executive. Upon such assumption the successor corporation or other
entity shall become obligated to perform the obligations of STERIS under this
Agreement and the term "STERIS" as used in this Agreement shall be deemed to
refer to such successor corporation or other entity.

     6.2 Notices. For purposes of this Agreement, notices and all other
communications provided for in this Agreement shall be in writing and shall be
deemed to have been duly given (a) when delivered in person (to Executive in the
case of notices to Executive and to the Secretary of STERIS in the case of
notices to STERIS) or (b) on the date actually received when sent by United
States registered mail, return receipt requested, postage prepaid, and
addressed, in the case of notices to STERIS, as follows:

                 STERIS Corporation
                 5960 Heisley Road
                 Mentor, Ohio 44060
                 Attention:   Secretary

and, in the case of notices to Executive, properly addressed to Executive at
Executive's most recent home address as shown on the records of STERIS, or such
other address as either party may have furnished to the other in writing in
accordance herewith, except that notices of change of address shall be effective
only upon receipt.

     6.3 Employment Rights. Nothing expressed or implied in this Agreement shall
create any right or duty on the part of STERIS or Executive to have Executive
continue as an officer of STERIS or to remain in the employment of STERIS.

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     6.4 Administration. STERIS shall be responsible for the general
administration of this Agreement and for making payments under this Agreement.
All fees and expenses billed by the Accounting Firm for services contemplated
under this Agreement shall be the responsibility of STERIS.

     6.5 Source of Payments. All payments under this Agreement shall be made
solely from the general assets of STERIS (or from a grantor trust, if any,
established by STERIS for purposes of making payments under this Agreement and
other similar agreements), and Executive shall have the rights of an unsecured
general creditor of STERIS with respect thereto.

     6.6 Validity. The invalidity or unenforceability of any provision of this
Agreement shall not affect the validity or enforceability of any other provision
of this Agreement which shall remain in full force and effect.

     6.7 Modification, Waiver, Etc. No provision of this Agreement may be
modified, waived, or discharged unless such waiver, modification, or discharge
is agreed to in a writing signed by Executive and STERIS. No waiver by either
party hereto at any time of any breach by the other party of, or compliance
with, any condition or provision of this Agreement to be performed by such other
party shall be deemed a waiver of similar or dissimilar provisions or conditions
at the same time or at any prior or subsequent time. No agreement or
representation, oral or otherwise, express or implied, with respect to the
subject matter hereof has been made by either party that is not set forth
expressly in this Agreement. This Agreement supercedes and replaces in its
entirety the Agreement, dated July 16, 1999, between STERIS and Executive (the
"Early Agreement") and such Early Agreement is hereby terminated and of no
further force or effect. This Agreement shall inure to the benefit of and be
enforceable by Executive's personal representatives, executors, administrators,
successors, heirs, and designees. This Agreement shall be governed by and
construed in accordance with the laws of the State of Ohio.

7.   Definitions.

     7.1 Accounting Firm. The term "Accounting Firm" means the independent
auditors of STERIS for the Fiscal Year preceding the year in which the Change of
Control occurred and such firm's successor or successors; provided, however, if
such firm is unable or unwilling to serve and perform in the capacity
contemplated by this Agreement, STERIS shall select another national accounting
firm of recognized standing to serve and perform in that capacity under this
Agreement, except that such other accounting firm shall not be the then
independent auditors for STERIS or any of its affiliates (as defined in Rule
12b-2 promulgated under the Securities Exchange Act of 1934, as amended).

     7.2 Base Salary. The term "Base Salary" means the salary payable to
Executive from time to time before any reduction for voluntary contributions to
any 401(k) plan or any other voluntary deferral. Base Salary does not include
imputed income from any payment by STERIS of any noncash benefits.

     7.3 Cause. The employment of Executive by STERIS or any of its Subsidiaries
shall have been terminated for "Cause" if the Executive's employment is
terminated and, prior to that termination of employment, any of the following
has occurred:

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     (a) Executive shall have been convicted of a felony,

     (b) Executive commits an act or series of acts of dishonesty in the course
     of Executive's employment which are materially inimical to the best
     interests of STERIS, all as determined in good faith by the vote of three
     fourths of all of the members of the Board of Directors of STERIS (other
     than Executive, if Executive is a Director of STERIS).

     (c) after being notified in writing by the Board of Directors of STERIS of
     the failure and having been given at least 30 days in which to cure the
     failure, Executive continues to unreasonably neglect Executive's duties and
     responsibilities as an executive of STERIS,

     (d) after being notified in writing by the Board of Directors of STERIS to
     cease any particular Competitive Activity, Executive intentionally
     continues to engage in that Competitive Activity while Executive remains in
     the employ of STERIS.

     7.4 Change of Control. A "Change of Control" shall be deemed to have
     occurred if at any time or from time to time while this Agreement is in
     effect:

     (a) any person (other than STERIS, any of its Subsidiaries, any employee
     benefit plan or employee stock ownership plan of STERIS, or any person
     organized, appointed, or established by STERIS for or pursuant to the terms
     of any such plan), alone or together with any of its affiliates, becomes
     the beneficial owner of 15% or more (but less than 50%) of the Common
     Shares then outstanding;

     (b) Any person (other than STERIS, any of its Subsidiaries, any employee
     benefit plan or employee stock ownership plan of STERIS, or any person
     organized, appointed, or established by STERIS for or pursuant to the terms
     of any such plan), alone or together with any of its affiliates, becomes
     the beneficial owner of 50% or more of the Common Shares then outstanding;

     (c) Any person commences or publicly announces an intention to commence a
     tender offer or exchange offer the consummation of which would result in
     the person becoming the beneficial owner of 15% or more of the Common
     Shares then outstanding;

     (d) At any time during any period of 24 consecutive months, individuals who
     were directors at the beginning of the 24-month period no longer constitute
     a majority of the members of the Board of Directors of STERIS, unless the
     election, or the nomination for election by STERIS's shareholders, of each
     director who was not a director at the beginning of the period is approved
     by at least a majority of the directors who (i) are in office at the time
     of the election or nomination and (ii) were directors at the beginning of
     the period;

     (e) A record date is established for determining shareholders entitled to
     vote upon (i) a merger or consolidation of STERIS with another corporation
     in which those persons who are shareholders of STERIS immediately before
     the merger or consolidation are to

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     receive or retain less than 60% of the stock of the surviving or continuing
     corporation, (ii) a sale or other disposition of all or substantially all
     of the assets of STERIS, or (iii) the dissolution of STERIS;

     (f) (i) STERIS is merged or consolidated with another corporation and those
     persons who were shareholders of STERIS immediately before the merger or
     consolidation receive or retain less than 60% of the stock of the surviving
     or continuing corporation, (ii) there occurs a sale or other disposition of
     all or substantially all of the assets of STERIS, or (iii) STERIS is
     dissolved; or

     (g) Any person who proposes to make a "control share acquisition" of
     STERIS, within the meaning of Section 1701.01(Z) of the Ohio General
     Corporation Law, submits or is required to submit an acquiring person
     statement to STERIS.

Notwithstanding anything herein to the contrary, if an event described in clause
(b), clause (d), or clause (f) above occurs, the occurrence of that event will
constitute an irrevocable Change of Control. Furthermore, notwithstanding
anything herein to the contrary, if an event described in clause (c) occurs, and
the Board of Directors either approves such offer or takes no action with
respect to such offer, then the occurrence of that event will constitute an
irrevocable Change of Control. On the other hand, notwithstanding anything
herein to the contrary, if an event described in clause (a), clause (e), or
clause (g) above occurs, or if an event described in clause (c) occurs and the
Board of Directors does not either approve such offer or take no action with
respect to such offer as described in the preceding sentence, and a majority of
those members of the Board of Directors who were Directors prior to such event
determine, within the 90-day period beginning on the date such event occurs,
that the event should not be treated as a Change of Control, then, from and
after the date that determination is made, that event will be treated as not
having occurred. If no such determination is made, a Change of Control resulting
from any of the events described in the immediately preceding sentence will
constitute an irrevocable Change of Control on the 91st day alter the occurrence
of the event.

     7.5 Competitive Activity. Executive shall be deemed to have engaged in
"Competitive Activity" if Executive engages, directly or indirectly and whether
as a director, officer, employee, agent, or independent contractor, in any
business or business activity in which STERIS or any of its Subsidiaries engages
(other than as a director, officer, or employee of STERIS or any of its
Subsidiaries).

     7.6 Disability. For purposes of this Agreement, Executive's employment will
have been terminated by STERIS by reason of "Disability" of Executive only if
(a) as a result of bodily injury or sickness, Executive has been unable to
perform Executive's normal duties for STERIS for a period of 180 consecutive
days, and (b) Executive begins to receive payments under a long term disability
plan sponsored by STERIS not later than 30 days after the Termination Date.

     7.7 Executive's Average Annual Incentive Compensation. Subject to the last
four sentences of this Subsection 7.7, the term "Executive's Average Annual
Incentive Compensation" means the highest of:

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     (a) the average of the dollar amounts of incentive compensation paid or
     payable to Executive under the MICP for each of the two Fiscal Years most
     recently ended before the first Change of Control occurring after execution
     of this Agreement,

     (b) the average of the dollar amounts of incentive compensation paid or
     payable to Executive under the MICP for each of the two Fiscal Years most
     recently ended before the Termination Date, and

     (c) the average dollar amount obtained by adding together (i) the amount of
     incentive compensation paid or payable to Executive under the MICP for the
     Fiscal Year most recently ended before the Termination Date and (ii)
     Executive's Target Annual Incentive Compensation and dividing the sum so
     obtained by two.

If Executive was not a participant in the MICP for any one or more of the Fiscal
Years referred to in this Subsection 7.7, the reference to that year shall be
ignored in determining the average under clause (a), (b), and/or (c) above, as
the case may be, and the "average," if any, determined under that clause shall
be the dollar amount of incentive compensation paid or payable to Executive
under the MICP for the other Fiscal Year referred to in that clause (or, in the
case of clause (c), the dollar amount of Executive's Target Annual Incentive
Compensation). Thus, for example, if Executive was not a participant in the MICP
for the second year preceding a Change of Control but was a participant in the
MICP for the year immediately preceding a Change of Control, the average
determined under clause (a) would be equal to the amount of incentive
compensation paid or payable to Executive under the MICP for the single year
immediately preceding the Change of Control. If Executive was a participant in
the MICP for only a part of one or more Fiscal Years referred to in this
Subsection 7.7, the dollar amount of incentive compensation paid or payable to
Executive under the MICP for that year, for purposes of determining the averages
referred to in clauses (a), (b), and/or (c), as the case may be, shall be
annualized. Thus, for example, if Executive was a participant in the MICP for
only three months of a particular Fiscal Year and was paid incentive
compensation under the MICP for that period equal to $3X, the annualized amount
of $12X would be used in determining the averages referred to in clauses (a),
(b), and/or (c), as the case may be.

     7.8  Executive's Target Annual Incentive Compensation. The term
"Executive's Target Annual Incentive Compensation" means the higher of (a) the
dollar amount that would have been payable to Executive under the MICP or the
Fiscal Year in which the Termination Date occurs had all relevant levels of
performance (whether corporate, personal, or other) been exactly at target
levels and had Executive remained in the employ of STERIS through the date on
which incentive compensation for that Fiscal Year was paid in full, or (b) the
dollar amount that would have been payable to Executive under the MICP for the
last Fiscal Year that ended before the occurrence of a Change of Control had all
relevant levels of performance for that Fiscal Year been exactly at target
levels.

     7.9  Fiscal Year. The term "Fiscal Year" means STERIS's fiscal year as in
effect from time to time.

     7.10 Mandatory Relocation. A "Mandatory Relocation" shall have occurred if,
at any time after a Change of Control, Executive is notified that Executive's
principal place of employment for STERIS is to be relocated, without Executive's
written consent, more than 50

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miles from where Executive's principal place of employment was located
immediately before the Change of Control.

     7.11 MICP. The term "MICP" means STERIS's Management Incentive Compensation
Plan as in effect for STERIS's 2000 Fiscal Year and any earlier or later year
and any similar plan in which Executive may have participated or that may be
implemented in place of the plan from time to time thereafter.

     7.12 Reduction of Compensation. A "Reduction of Compensation" shall have
occurred if either or both of the following occur at any time after a Change of
Control:

     (a)  Executive's Base Salary is reduced or

     (b)  either

          (i)  the MICP, and/or Executive's level of participation in the MICP,
          is altered for any year in such a way as to reduce Executive's
          opportunity to earn incentive compensation under the MICP for that
          year below the level of that opportunity as it existed immediately
          before the Change of Control, or

          (ii) the amount of incentive compensation paid to Executive for any
          period after the Change of Control is below Executive's Target Annual
          Incentive Compensation.

     7.13 Subsidiary. A "Subsidiary" means any corporation, partnership, or
other entity a majority of the voting control of which is directly or indirectly
owned or controlled at the time in question by STERIS.

     7.14 Termination Date. The term "Termination Date" means the date on which
Executive's employment with STERIS terminates.

IN WITNESS WHEREOF, the parties have executed this Agreement as of the date
first written above.

                                           STERIS Corporation


                                           By  /s/ David C. Dvorak
                                             -----------------------------------
                                             Title:   Senior Vice President and
                                                      General Counsel

                                           "EXECUTIVE"


                                           /s/ Les C. Vinney
                                           -------------------------------------
                                           LES C. VINNEY

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