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                                                                    Exhibit 3(k)
                            CERTIFICATE OF AMENDMENT
                         OF CERTIFICATE OF INCORPORATION
                             OF CANTEL MEDICAL CORP.

                    -----------------------------------------

                    Adopted in accordance with the provisions
                          of Section 242 of the General
                    Corporation Law of the State of Delaware
                    -----------------------------------------







         We, James P. Reilly, President, and Darwin C. Dornbush, Secretary of
Cantel Medical Corp., a corporation existing under the laws of the State of
Delaware, do hereby certify as follows:

         FIRST:      That the Certificate of Incorporation of said corporation
has been amended as follows:

               By striking out Article THIRTEENTH, as it now exists and
         inserting in lieu and instead thereof the following:

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               "THIRTEENTH: The Corporation shall, to the fullest extent
         permitted by Section 145 of the General Corporation Law of the State of
         Delaware, as the same may be amended and supplemented, or by any
         successor thereto, indemnify any and all persons whom it shall have
         power to indemnify under said section from and against any and all of
         the expenses, liabilities, or other matters referred to in or covered
         by said section. Such right to indemnification shall continue as to a
         person who has ceased to be a director, officer, employee or agent and
         shall inure to the benefit of heirs, executors and administrators of
         such a person. The indemnification provided for herein shall not be
         deemed exclusive of any other rights of which those seeking
         indemnification may be entitled under any By-law, agreement, vote of
         stockholders or disinterested directors or otherwise."

         SECOND: That such amendment has been duly adopted in accordance with
the provisions of Section 242(b)(1) of the General Corporation Law of the State
of Delaware by the affirmative vote of the holders of a majority of the
outstanding common stock entitled to vote thereon at a meeting of holders of
common stock.

         IN WITNESS WHEREOF, we have signed this Certificate this 6th day of
September, 2001.

                                          CANTEL MEDICAL CORP.



                                          /s/ JAMES P. REILLY
                                          ------------------------------
                                          James P. Reilly, President



                                  ATTEST: /s/ DARWIN C. DORNBUSH
                                          -----------------------------
                                          Darwin C. Dornbush, Secretary