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Exhibit 10(q)

MANAGEMENT AGREEMENT

AGREEMENT made as of this 1st day of September, 1996 by and between Minntech Corporation, a Minnesota corporation, with its principal executive office at
Plymouth, Minnesota ("Company") and Robert W. Johnson residing at 5332 Matterhorn Drive, Fridley, Minnesota 55421 (the "Executive").

WHEREAS,
Company considers the establishment and maintenance of a sound and vital management to be essential to protecting and enhancing the best interests of Company and its
shareholders; and

WHEREAS,
the Executive is expected to continue to make a significant contribution to the profitability, growth and financial strength of Company; and

WHEREAS,
Company, as a publicly held corporation, recognizes that the possibility of a Change in Control may exist and that such possibility, and the uncertainty and questions which
it may raise among management, may result in the departure or distraction of the Executive in the performance of the Executive's duties to the detriment of Company and its shareholders; and

WHEREAS,
the Executive is willing to continue to be an employee of Company upon the understanding that Company will provide income security if the Executive's employment is terminated
under certain terms and conditions; and

WHEREAS,
it is in the best interests of Company and its shareholders to reinforce and encourage the continued attention and dedication of management personnel, including the
Executive, to their assigned duties without distraction and to increase the likelihood of the continued availability to Company of the Executive in the event of a Change in Control.

THEREFORE,
in consideration of the foregoing and other respective covenants and agreements of the parties herein contained, the parties hereto agree as follows:

1.Term of Agreement.This Agreement shall commence on the date hereof and shall continue in effect
until such time as Company notifies the Executive or the Executive notifies Company of termination of this Agreement; provided, however, that in no event may this Agreement be terminated prior to two
years from the date hereof, and notice of termination on the second or any subsequent anniversary date hereof must be given by Company in writing mailed to the Executive at his or her last known
address within 60 days prior to such anniversary date or by the Executive by notice in writing mailed to Company at the principal executive office of Company within 60 days prior to such
anniversary date. If no such notice is given, then the term of this Agreement shall be extended for additional periods of one year. Notwithstanding the preceding sentence, if a Change in Control
occurs during the term of this Agreement (including any extension hereof), this Agreement shall continue in effect for a period of 36 months from the date of the occurrence of a Change in
Control. Except as provided in Section 2(b) or Section 3(e) of this Agreement, nothing stated herein shall limit the right of the Executive or Company to terminate the employment of the
Executive with Company at any time prior to the expiration of the term of this Agreement, with or without Cause (as defined in Section 3(b) of this Agreement) and for any reason whatsoever,
subject to the right of the Executive to receive any payment and other benefits that may be due pursuant to the terms and conditions of Section 4 of this Agreement.

2.Change in Control.No amounts shall be payable hereunder unless a Change in Control, as set forth
below, shall occur during the term of this Agreement.



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3.Termination Following Change in Control.If a Change in Control shall occur during the term of this
Agreement, the Executive shall be entitled to the payments and other benefits provided in subsection 4(d) in the event of the termination of the Executive's employment with Company unless the
Executive's termination is (A) because of the Executive's death, (B) by Company for Cause or Disability, or (C) by the Executive other than for Good Reason.



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4.Compensation Upon Termination or During Disability.Upon termination of the Executive's employment
(or, with respect to Section 4(a), during a period of Disability) following a Change in Control, as defined in Section 2(a), of Company or if there shall be a termination by Company of
the Executive's employment prior to a Change in Control, or the Executive shall terminate employment with Company for Good Reason prior to a Change in Control (for which purpose the references in
Section 3(c) to changes from circumstances existing immediately prior to or at the time of a Change in Control that constitute Good Reason for termination shall instead be deemed to be
references to circumstances existing immediately prior to or at the time that the Change in Control is first anticipated), and the Executive reasonably demonstrates that such termination by Company or
event constituting Good Reason for termination by the Executive (x) was requested by a third party that had previously taken other steps reasonably calculated to result in a Change in Control
described in Section 2(a)(i), 2(a)(ii), 2(a)(iii) or 2(a)(iv) and ultimately resulting in such a Change in Control following termination of the Executive's employment or
(y) otherwise arose in connection with or in anticipation of a Change in Control described in Section 2(a)(i), 2(a)(ii), 2(a)(iii) or 2(a)(iv) that ultimately occurs
following termination of the Executive's employment, the Executive shall be entitled to the following benefits:



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5.Funding of Payments.In order to assure the performance of Company or its successor of its
obligations under this Agreement, Company may deposit in trust an amount equal to the maximum payment that will be due the Executive under the terms hereof. Under a written trust instrument, the
Trustee shall be instructed to pay to the Executive (or the Executive's legal representative, as the case may be) the amount to which the Executive shall be entitled under the terms hereof, and the
balance, if any, of the trust not so paid or reserved for payment shall be repaid to Company. If Company deposits funds in trust, payment shall be made no later than the occurrence of the first Change
in Control described in Section 2(a)(i), 2(a)(ii), 2(a)(iii) or 2(a)(iv). Company shall give notice of such a Change in Control to any such trustee upon any occurrence as defined herein.
If and to the extent that the Executive becomes a beneficiary of any such funds deposited in trust, Company shall give prompt notice to the Executive, which shall include a copy of the trust
instrument and amendments from time to time. The rights of the Executive under such trust instrument shall be enforceable against Company and any trustees named therein, as though the provisions of
said trust were incorporated into this

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Agreement. If and to the extent there are not amounts in trust sufficient to pay the Executive under this Agreement, Company shall remain liable for any and all payments due to the Executive. In
accordance with the terms of such trust, at all times during the term of this Agreement, the Executive shall have no rights, other than as an unsecured general creditor of Company, to any amounts held
in trust and all trust assets shall be general assets of Company and subject to the claims of creditors of Company.

6.Successors; Binding Agreement.



7.Notice.For the purpose of this Agreement, notices and all other communications provided for in the
Agreement shall be in writing and shall be deemed to have been duly given when delivered or mailed by United States registered or certified mail, return receipt requested, postage
pre-paid, addressed to the last known residence address of the Executive or in the case of Company, to its principal executive office to the attention of each of the then directors of
Company with a copy to its Secretary, or to such other address as either party may have furnished to the other in writing in accordance herewith, except that notice of change of address shall be
effective only upon receipt.

8.Miscellaneous.No provision of this Agreement may be modified, waived or discharged unless such
waiver, modification or discharge is agreed to in writing and signed by the parties. No waiver by either party hereto at any time of any breach by the other party to this Agreement 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 or at any prior to similar
time. No legally binding or enforceable agreements or representations, oral or otherwise, express or implied, with respect to the subject matter hereof that remain in effect have been made by either
party which are not expressly set forth in this Agreement. The validity, interpretation, construction and performance of this Agreement shall be governed by the laws of the State of Minnesota.

9.Validity.The invalidity or unenforceability or 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.

|MINNTECH CORPORATION |  | EXECUTIVE:            
|-------------------- |  | ----------------------
|By                   |  | /s/ Louis C. Cosentino
|                     |  |                       
|                     |  | Its President         

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AMENDMENT TO MANAGEMENT AGREEMENT

This AMENDMENT made as of this 1st day of April, 1997, by and between Minntech Corporation, a Minnesota corporation (the "Company") and Robert W. Johnson, a
Minnesota resident (the "Executive"), as an amendment to the Management Agreement dated as of September 1, 1996, between the Company and the Executive.

WHEREAS,
the Company and the Executive entered into the Management Agreement for the reasons set forth in the recitals to the Management Agreement; and

WHEREAS,
for the reasons set forth in the recitals to the Management Agreement, the Company has determined that it is in the best interests of the Company and its shareholders to
provide for increased payments to the Executive upon the termination of the Executive's employment in certain circumstances following a Change in Control of the Company or as otherwise set forth in
the lead-in sentence to Section 4 of the Management Agreement.

THEREFORE,
in consideration of the foregoing, the parties hereto agree to amend Section 4(d)(ii) of the Management Agreement in its entirety to read as follows:



The
Management Agreement, subject only to this Amendment and any other amendments entered into in accordance with Section 8 of the Management Agreement, shall remain in full
force and effect without modification. All references in the Management Agreement to "this Agreement" shall be deemed to be references to the Management Agreement as amended by this Amendment. All
terms used in this Amendment which are not defined in this Amendment shall have the meanings set forth in the Management Agreement.

IN
WITNESS WHEREOF, the parties hereto have signed this Amendment as of the date above written.

|MINNTECH CORPORATION |  | EXECUTIVE:              
|-------------------- |  | ------------------------
|By                   |  | /s/ Thomas J. McGoldrick
|                     |  |                         
|                     |  | Its President           

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