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                          AMENDMENT NO. 1 TO AGREEMENT
                               AND PLAN OF MERGER

         THIS AMENDMENT NO. 1 TO AGREEMENT AND PLAN OF MERGER (this "AMENDMENT")
is dated as of November 14, 2000 and is by and among Hanover Compressor Company,
a Delaware corporation ("PARENT"), Caddo Acquisition Corporation, an Oklahoma
corporation and a direct, wholly owned subsidiary of Parent ("MERGER SUB"), and
OEC Compression Corporation, an Oklahoma corporation (the "COMPANY"). Terms used
and not defined herein shall have the meanings assigned to them in the Agreement
and Plan of Merger dated as of July 13, 2000 by and among the Parent, Merger Sub
and the Company (the "MERGER AGREEMENT").

                                    RECITALS:

         A.   Parent, Merger Sub and the Company entered into the Merger
Agreement as of July 13, 2000; and

         B.   Parent, Merger Sub and the Company desire to amend the Merger
Agreement as set forth in this Amendment.

                                   AGREEMENT:

         NOW, THEREFORE, in consideration of the foregoing and the mutual
covenants and agreements herein contained, and intending to be legally bound
hereby, Parent, Merger Sub and the Company hereby agree as follows:

         1.   The second sentence of Section 3.2 of the Merger Agreement is
amended to read in its entirety as follows: "As of the date hereof, (i)
37,060,776 shares of Company Common Stock are issued and outstanding, all of
which are validly issued, fully paid and nonassessable, (ii) 320,445 shares of
Company Common Stock are held in the treasury of the Company or by Subsidiaries
of the Company, and (iii) no shares of Company Preferred Stock are issued and
outstanding."

         2.   Sections 5.11 and 6.3(g) of the Merger Agreement are deleted in
their entirety. Parent and Merger Sub hereby waive any rights they may have as a
result of the breach or non-fulfillment of the requirements of such Sections
prior to the date of this Amendment.

         3.   Section 6.3(d) of the Merger Agreement is amended to read in its
entirety as follows:

              (d) ABSENCE OF CERTAIN CHANGES OR EVENTS. Since the date of this
         Agreement there shall not have been any event, development or change
         of circumstance that constitutes, has had, or, individually or in the
         aggregate, could be expected to have a Company Material Adverse Effect.
         Solely for purposes of this Section 6.3(d), a Company Material Adverse
         Effect shall have been deemed to occur only if it results from:
         (i) natural disasters or acts of God; (ii) war, terrorism or civil
         strife; (iii) criminal acts or civil fraud; or (iv) willful misconduct
         of the Company's officers.

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         4.   Section 7.1(b) of the Merger Agreement is amended to read in its
entirety as follows:

              (b) by either Parent or the Company if the Merger shall not
         have been consummated by March 1, 2001 (the "OUTSIDE DATE"), provided
         that the right to terminate this Agreement under this Section 7.1(b)
         shall not be available to any party whose failure to fulfill any
         obligation under this Agreement has been the cause of or resulted in
         the failure of the Merger to occur on or before such date); or

         5.   The following is added as the last sentence of Section 8.3 of the
Merger Agreement: "KNOWLEDGE" or "TO THE KNOWLEDGE OF" Parent or Merger Sub
means the actual knowledge of Michael J. McGhan, William S. Goldberg and Charles
A. Erwin.

         6.   As of the date of this Amendment, to the knowledge of Parent and
Merger Sub, there has not been any event, development or change of circumstance
that constitutes, has had, or, individually or in the aggregate, could be
expected to have a Company Material Adverse Effect (as such term is used in
Section 6.3(d) of the Merger Agreement, as amended by this Amendment).

         7.   As of the date of this Amendment, to the knowledge of Parent and
Merger Sub, the Company has not breached any of the representations and
warranties contained in Article III of the Merger Agreement.

         8.   The Merger Agreement, as amended by this Amendment, and all
documents and instruments referred to in the Merger Agreement (a) constitute the
entire agreement and supersede all prior agreements and understandings, both
written and oral, among the parties with respect to the subject matter hereof,
and (b) except as provided in Section 5.12 of the Merger Agreement, are not
intended to confer upon any person other than the parties hereto any rights or
remedies hereunder; provided that the Confidentiality Agreements shall remain in
full force and effect until the Effective Time.

         9.   The laws of the State of Oklahoma shall govern the interpretation,
validity and performance of the terms of this Amendment, regardless of the law
that might be applied under principles of conflicts of law.

         10.  This Amendment may be executed in two or more counterparts, all of
which shall be considered one and the same agreement and shall become effective
when two or more counterparts have been signed by each of the parties and
delivered to the other parties, it being understood that all parties need not
sign the same counterpart.

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         IN WITNESS WHEREOF, each of the parties hereto has executed this
Amendment or caused this Amendment to be duly executed on its behalf by its
officer thereunto duly authorized, as of the day and year first above written.

                                       HANOVER COMPRESSOR COMPANY
                                       a Delaware corporation


                                       By:
                                          -------------------------------------
                                       Name:  Michael J. McGhan
                                       Title:  Chief Executive Officer

                                       CADDO ACQUISITION CORPORATION
                                       an Oklahoma corporation


                                       By:
                                          -------------------------------------
                                       Name:  Michael J. McGhan
                                       Title:  Chief Executive Officer

                                       OEC COMPRESSION CORPORATION
                                       an Oklahoma corporation


                                       By:
                                          -------------------------------------
                                       Name:
                                            -----------------------------------
                                       Title:
                                             ----------------------------------