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                                                                    EXHIBIT 31.1

                        CERTIFICATION OF PERIODIC REPORT

I, Charles D. Johnston, certify that:

   1. I have reviewed this quarterly report on Form 10-QSB of QualMark
      Corporation (the "small business issuer");

   2. Based on my knowledge, this report does not contain any untrue statements
      of material fact or omit to state a material fact necessary to make the
      statements made, in light of the circumstances under which such statements
      were made, not misleading with respect to the period covered by this
      report;

   3. Based on my knowledge, the financial statements, and other financial
      information included in this report, fairly present in all material
      respects the financial condition, results of operations and cash flows of
      the small business issuer as of, and for, the periods presented in this
      report;

   4. The small business issuer's other certifying officer and I are responsible
      for establishing and maintaining disclosure controls and procedures (as
      defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the small
      business issuer and have:

      a) Designed such disclosure controls and procedures, or caused such
      disclosure controls and procedures to be designed under our supervision,
      to ensure that material information relating to the small business issuer,
      including its consolidated subsidiaries, is made known to us by others
      within those entities, particularly during the period in which this report
      is being prepared;

      b) [Paragraph omitted in accordance with SEC transition instructions
      contained in SEC release 34-47986.]

      c) Evaluated the effectiveness of the small business issuer's disclosure
      controls and procedures and presented in this report our conclusions about
      the effectiveness of the disclosure controls and procedures, as of the end
      of the period covered by this report based on such evaluation; and

      d) Disclosed in this report any change in the small business issuer's
      internal control over financial reporting that occurred during the small
      business issuer's most recent fiscal quarter that has materially affected,
      or is reasonably likely to materially affect, the small business issuer's
      internal control over financial reporting; and

   5. The small business issuer's other certifying officer and I have disclosed,
      based on our most recent evaluation of internal control over financial
      reporting, to the small business issuer's auditors and the audit committee
      of small business issuer's board of directors (or persons performing the
      equivalent function):

      a) All significant deficiencies and material weaknesses in the design or
      operation of internal control over financial reporting which are
      reasonably likely to adversely affect the small business issuer's ability
      to record, process, summarize and report financial information; and

      b) Any fraud, whether or not material, that involves management or other
      employees who have a significant role in the small business issuer's
      internal control over financial reporting.

Date: May 13, 2005

                                   /s/ Charles D. Johnston
                                   -----------------------------------
                                   Charles D. Johnston
                                   President & Chief Executive Officer

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