<PAGE>
                                                                    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 14, 2004

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