Exhibit 31.1
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                                  CERTIFICATION
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I, Brad A. Hummel, President and Chief Executive Officer of Prime Medical
Services, Inc., certify that:

  1.  I have reviewed this quarterly report on Form 10-Q of Prime Medical
      Services, Inc.;

  2.  Based on my knowledge, this report does not contain any untrue
      statement of a 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 registrant as of, and for, the periods presented in this report;

  4.  The registrant's other certifying officer(s) 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
      registrant 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
      registrant, 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) Evaluated the effectiveness of the registrant'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

      (c) Disclosed in this report any change in the registrant's internal
      control over financial reporting that occurred during the registrant's
      most recent fiscal quarter (the registrant's fourth fiscal quarter in
      the case of an annual report) that has materially affected, or is
      reasonably likely to materially affect, the registrant's internal
      control over financial reporting; and

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

      (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 registrant'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 registrant's
      internal control over financial reporting.


Date:  August 12, 2003                By:  /s/ Brad A. Hummel
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                                           Brad A. Hummel
                                           President and Chief Executive Officer