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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:  August 13, 2004

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