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                              MINNTECH CORPORATION
                           BOARD OF DIRECTORS MEETING
                                SEPTEMBER 26,1996



     RESOLVED that the 1989 Stock Plan (the "1989 Plan") of the Company, as
previously amended, is hereby further amended effective as of September 26,
1996, as follows, provided that no such amendment shall impair the rights of an
optionee (unless consent of such optionee shall have been obtained) under a
Stock Option that was previously granted to such optionee.

          1.   Paragraph h. of Section 1 of the 1989 Plan is deleted.

          2.   A new Paragraph v. is hereby added to Section 1 of the 1989 Plan
to read as follows:

          v.   "EXCHANGE ACT" means the Securities Exchange Act of 1934, as
     amended, or any successor statute thereto.

          3.   Paragraph 1. of Section 1 of the 1989 Plan is amended in its
entirety to read as follows:

          1."NON-EMPLOYEE DIRECTOR" shall have the meaning set forth in Rule
     16b-3(b)(3) under the Exchange Act, or any successor rule thereto.

          4.   The first paragraph of Section 2 of the 1989 Plan is amended in
its entirety to read as follows:

          The Plan shall be administered by the Board of Directors or a
     Committee of not less than three Non-Employee Directors, who shall be
     appointed by the Board of directors of the Company and who shall serve at
     the pleasure of the Board.

          5.   Paragraph (c) of Section 5 of the 1989 Plan is amended in its
entirety to read as follows:

          (c)  EXERCISABILITY.  Stock Options shall be exercisable at such 
     time or times as determined by the Committee at or after grant.  If the 
     Committee provides, in its discretion, that any option is exercisable 
     only in installments, the Committee may waive such installment exercise 
     provisions at any time.  Notwithstanding the foregoing or any other 
     provision of this Plan, unless the Stock Option Agreement provides 
     otherwise, (1) any Stock Option granted under this Plan on or prior to 
     September 26, 1996 (including options granted to Non-Employee 
     Directors), that shall not have

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     previously expired shall be immediately exercisable in full, without regard
     to any installment exercise provisions, for a period specified by the
     Company, but not to exceed sixty (60) days, prior to the occurrence of any
     of the following events: (i) dissolution or liquidation of the Company
     other than in conjunction with a bankruptcy of the Company or any similar
     occurrence, (ii any merger, consolidation, acquisition, separation,
     reorganization, or similar occurrence, where the Company will not be the
     surviving entity or (iii) the transfer of substantially all of the assets
     of the Company or 75% or more of the outstanding Stock of the Company and,
     in addition, (2) any Stock Option granted under this Plan, whether prior
     to, on or after September 26, 1996 (including options granted to Non-
     Employee Directors), that shall not have previously expired shall be
     immediately exercisable in full, without regard to any installment exercise
     provisions, upon the occurrence of a Change in Control.  For purposes of
     this Plan, a "Change in Control" of the Company shall be deemed to occur if
     any of the following occur:

               (1)  Any "person" (as such term is used in Sections 13(d) and
          14(d) of the Exchange Act) acquires or becomes a "beneficial owner"
          (as defined in Rule 13d-3 or any successor rule under the Exchange
          Act), directly or indirectly, of securities of the Company
          representing 30% or more of the combined voting power of the Company's
          then outstanding securities entitled to vote generally in the election
          of directors ("Voting Securities"), provided, however, that the
          following shall not constitute a Change in Control pursuant to this
          paragraph (c)(1):

                    (A)  any acquisition or beneficial ownership by the Company
               or a Subsidiary;

                    (B)  any acquisition or beneficial ownership by any employee
               benefit plan (or related trust) sponsored or maintained by the
               Company or one or more of its Subsidiaries;

                    (C)  any acquisition or beneficial ownership by any
               corporation with respect to which, immediately following such
               acquisition, more than 70% of both the combined voting power of
               the Company's then outstanding Voting Securities and the Stock of
               the Company is then beneficially owned, directly or indirectly,
               by all or substantially all of the persons who beneficially owned
               Voting Securities and Stock of the Company immediately prior to
               such acquisition in substantially the same proportions as their
               ownership of such Voting Securities and Stock, as the case may
               be, immediately prior to such acquisition;


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               (2)  A majority of the members of the Board of Directors of the
          Company shall not be Continuing Directors.  "Continuing Directors"
          shall mean: (A) individuals who, on the date hereof, are directors of
          the Company, (B) individuals elected as directors of the Company
          subsequent to the date hereof for whose election proxies shall have
          been solicited by the Board of Directors of the Company or (C) any
          individual elected or appointed by the Board of Directors of the
          Company to fill vacancies on the Board of Directors of the Company
          caused by death or resignation (but not by removal) or to fill newly-
          created directorships;

               (3)  Approval by the shareholders of the Company of a
          reorganization, merger or consolidation of the Company (other than a
          merger or consolidation with a subsidiary of the Company) or a
          statutory exchange of outstanding Voting Securities of the Company,
          unless immediately following such reorganization, merger,
          consolidation or exchange, all or substantially all of the persons who
          were the beneficial owners, respectively, of Voting Securities and
          Stock of the Company immediately prior to such reorganization, merger,
          consolidation or exchange beneficially own, directly or indirectly,
          more than 70% of, respectively, the combined voting power of the then
          outstanding voting securities entitled to vote generally in the
          election of directors and the then outstanding shares of common stock,
          as the case may be, of the corporation resulting from such
          reorganization, merger, consolidation or exchange in substantially the
          same proportions as their ownership, immediately prior to such
          reorganization, merger, consolidation or exchange, of the Voting
          Securities and Stock of the Company, as the case may be; or

               (4)  Approval by the shareholders of the Company of (x) a
          complete liquidation or dissolution of the Company or (y) the sale or
          other disposition of all or substantially all of the assets of the
          Company (in one or a series of transactions), other than to a
          corporation with respect to which, immediately following such sale or
          other disposition, more than 70% of, respectively, the combined voting
          power of the then outstanding voting securities of such coporation 
          entitled to vote generally in the election of directors and the then 
          outstanding shares of common stock of such corporation is then
          beneficially owned, directly or indirectly, by all or substantially
          all of the persons who were the beneficial owners, respectively, of
          the Voting Securities and Stock of the Company immediately prior to
          such sale or other disposition in substantially the same proportions
          as their ownership, immediately prior to such sale or other
          disposition, of the Voting Securities and Stock of the Company, as the
          case may be.


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          6.   Paragraph (e) of Section 5 of the 1989 Plan is amended in its
entirety to read as follows:

          (e)  NON-TRANSFERABILITY OF OPTIONS. No Stock Options shall be 
     transferable by the optionee otherwise than by will or by the laws of 
     descent and distribution, and all Stock Options shall be exercisable 
     during the optionee's lifetime, only by the optionee; provided, however, 
     that any optionee may transfer any Non-Qualified Stock Option, whether 
     granted prior to, on or after September 26, 1996 (including any such 
     options granted to Non-Employee Directors), to members of his or her 
     immediate family (i.e., his or her children, grandchildren and spouse) 
     or to one or more trusts for the benefit of such family members or 
     partnerships in which such family members are the only partners, if the 
     optionee does not receive any consideration for the transfer.  Any 
     Non-Qualified Stock Options held by any such transferee shall continue 
     to be subject to the same terms and conditions that were applicable to 
     such Non-Qualified Stock Options immediately prior to their transfer.

          7.   Paragraph (c)(i) of Section 7 of the 1989 Plan is amended in its
entirety to read as follows:

          (i)  Subject to the provisions of this Plan and the award agreement,
     during a period set by the Committee commencing with the date of such award
     (the "Restriction Period"), the participant shall not be permitted to sell,
     transfer, pledge or assign shares of Restricted Stock awarded under the
     Plan; provided, however, that the participant may transfer any Restricted
     Stock, whether granted prior to, on or after September 26, 1996, to members
     of his or her immediate family (i.e., his or her children, grandchildren
     and spouse) or to one or more trusts for the benefit of such family members
     or partnerships in which such family members are the only partners, if the
     participant does not receive any consideration for the transfer. Any
     Restricted Stock held by any such transferee shall continue to be subject
     to the same terms and conditions that were applicable to such Restricted
     Stock immediately prior to its transfer. In no event shall the Restriction
     Period be less than one (1) year. Within these limits, the Committee may
     provide for the lapse of such restrictions in installments where deemed
     appropriate.

          8.   Paragraph (c)(v) of Section 7 of the 1989 Plan is hereby amended
in its entirety to read as follows:

          (v)  Notwithstanding the foregoing, all restrictions with respect to
     any participant's shares of Restricted Stock that shall not previously have
     been forfeited shall lapse immediately upon the occurrence of a Change in
     Control.

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          9.   Paragraph (b)(i) Of Section 8 of the 1989 Plan is amended in its
entirety to read as follows:

          (i)  Subject to the provisions of this Plan and the award agreement,
     Deferred Stock awards may not be sold, assigned, transferred, pledged or
     otherwise encumbered during the Deferral Period; provided, however, that
     any participant may transfer any Deferred Stock, whether granted prior to,
     on or after September 26, 1996, to members of his or her immediate family
     (i.e., his or her children, grandchildren and spouse) or to one or more
     trusts for the benefit of such family members or partnerships in which such
     family members are the only partners if the participant does not receive
     any consideration for the transfer.  Any Deferred Stock held by any such
     transferee shall continue to be subject to the same terms and conditions
     that were applicable to such Deferred Stock immediately prior to its
     transfer and the transferee shall be deemed to be the participant for
     purposes of making the election referred to in paragraph (b)(v) of this
     Section 8. In no event shall the Deferral Period be less than one (1) year.
     At the expiration of the Deferral Period (or elective Deferral Period,
     where applicable), share certificates shall be delivered to the
     participant, transferee, or their respective legal representative, in a
     number equal to the shares covered by the Deferred Stock award.

          10.  A new paragraph (b)(vii) is hereby added to Section 8 of the 1989
Plan to read as follows:

          (vii)     Notwithstanding the foregoing, the Deferral Period (or
     Elective Deferred Period, where applicable) with respect to a participant's
     Deferred Stock that shall not previously have been forfeited shall expire
     and share certificates shall be delivered to the participant, or his legal
     representative, in a number equal to the shares covered by the Deferred
     Stock award upon the occurrence of a Change in Control.

          11.  A new paragraph (g) is hereby added to Section 12 of the 1989
Plan to read as follows:

          (g)  In the event of (a) the proposed dissolution or liquidation of
     the Company, (b) a proposed sale of substantially all of the assets of the
     Company or (c) a proposed merger or consolidation of the Company with or
     into any other entity, regardless of whether the Company is the surviving
     corporation, or a proposed statutory share exchange with any other entity
     (the actual effective date of the dissolution, liquidation, sale, merger,
     consolidation or exchange being herein called an "Event"), the Committee
     may, but shall not be obligated to, either (i) if the Event is a merger,
     consolidation or statutory share exchange, make appropriate provision for
     the protection of outstanding Stock Options, Stock Appreciation Rights,
     Restricted Stock and Deferred Stock awards granted under this Plan by the
     substitution, in lieu of such Stock Options, Stock Appreciation Rights,
     Restricted Stock or Deferred Stock awards,

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     of options to purchase, or stock appreciation rights with respect to, 
     appropriate voting common stock (or of restricted voting common stock 
     or, with respect to Deferred Stock Awards, voting common stock), as the 
     case may be (the "Survivor's Stock") of the corporation surviving any 
     such merger or consolidation or, if appropriate, the parent corporation 
     of the Company or such surviving corporation, or, alternatively with 
     respect to Stock Options or Stock Appreciation Rights, by the delivery 
     of a number of shares of the Survivor's Stock which has a Fair Market 
     Value as of the effective date of such merger, consolidation or 
     statutory share exchange equal to the product of (x) the excess of (A) 
     the Event Proceeds per Share (as hereinafter defined) covered by the 
     Stock Options or Stock Appreciation Rights as of such effective date 
     over (B) the exercise price per share of the shares of Stock subject to 
     such Stock Options or used to measure the value of such Stock 
     Appreciation Rights, times (y) the number of shares covered by such 
     Stock Options or Stock Appreciation Rights, as the case may be, or (ii) 
     declare, at least twenty days prior to the Event, and provide written 
     notice to each optionee of the declaration, that each outstanding Stock 
     Option and Stock Appreciation Right, whether or not then exercisable, 
     shall be canceled at the time of, or immediately prior to the occurrence 
     of, the Event (unless it shall have been exercised prior to the 
     occurrence of the Event).  In connection with any declaration pursuant 
     to clause (ii) of the preceding sentence, the Committee may, but shall 
     not be obligated to, cause payment to be made, within twenty days after 
     the Event in exchange for each canceled Stock Option and Stock 
     Appreciation Right, of cash equal to the amount (if any), for each share 
     of Stock covered by the canceled option or used to measure the value of 
     a Stock Appreciation Right, by which the Event Proceeds per share of 
     Stock (as hereinafter defined) exceeds the exercise price per Share 
     covered by such Stock Option or used to measure the value of a Stock 
     Appreciation Right.  At the time of any declaration pursuant to clause 
     (ii) of the first sentence of this paragraph (g), each Stock Option and 
     Stock Appreciation Right that has not previously expired or have been 
     terminated or canceled pursuant to this Plan shall immediately become 
     exercisable in full and each optionee or holder of a stock appreciation 
     right shall have the right, during the period preceding the time of 
     cancellation of the Stock Option or Stock Appreciation Right, to 
     exercise his or her Stock Option or Stock Appreciation Right as to all 
     or any part of the Shares covered thereby or used to measure the value 
     thereof.  In the event of a declaration pursuant to clause (ii) of the 
     first sentence of this paragraph (g), each outstanding Stock Option and 
     Stock Appreciation Right granted pursuant to this Plan that shall not 
     have been exercised prior to the Event shall be canceled at the time of, 
     or immediately prior to, the Event, as provided in the declaration, 
     subject to the payment obligations of the Company, if any, provided in 
     this paragraph (g). Notwithstanding the foregoing, no person holding a 
     Stock Option or Stock Appreciation Right shall be entitled to the 
     payment provided in this paragraph (g) if a Stock Option or Stock 
     Appreciation Right shall have expired pursuant to this Plan.  For 
     purposes of this paragraph (g), "Event Proceeds per Share" shall mean 
     the cash plus the fair market value, as determined in good faith by the 
     Committee, of the non-cash consideration to be received per share of 
     Stock by the

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     shareholders of the Company upon the occurrence of the Event.  Nothing
     stated in this paragraph (g) shall impair the rights of an optionee (unless
     the consent of the optionee shall have been obtained) under a Stock Option
     granted to such optionee on or prior to September 26, 1996, the date of
     adoption of the Amendment to this Plan to add paragraph (g).


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