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                                 FIRST AMENDMENT
                               TO CREDIT AGREEMENT



     This First Amendment ("Amendment") is made as of the 5th day of April,
2000, by and between IRI INTERNATIONAL CORPORATION (the "Borrower") and BANK
ONE, TEXAS, N.A. (the "Lender").

     WHEREAS, the Borrower and the Lender entered into a Loan Agreement dated
December 29, 1999, as amended (if applicable) (the "Credit Agreement"); and

     WHEREAS, the parties hereto desire to amend the Credit Agreement as set
forth below:

     NOW, THEREFORE, the parties hereto agree as follows:

                                   ARTICLE I

     Section 1.01  Capitalized terms not defined herein shall have the meaning
ascribed in the Credit Agreement.

                                   ARTICLE II

     Section 2.01  Section 7.13 of the Credit Agreement is hereby amended in its
entirety as follows:

               Section 7.13 Accounts with Lender. Borrower shall transfer all of
               its primary operating accounts and treasury management to Lender
               by June 30, 2000.


                                  ARTICLE III

     Section 3.01  This Amendment shall become effective only after it is fully
executed by the Borrower and the Lender and the Lender shall have received from
the Borrower the following documents: First Amendment to Credit Agreement.
Except as amended by this Amendment, the Credit Agreement shall remain in full
force and effect in accordance with its terms.


                                   ARTICLE IV

     Section 4.01 The Borrower represents and warrants that (a) the
representations and warranties contained in the Credit Agreement are true and
correct in all material respects as of the date of this Amendment, (b) no
condition, act or event which could constitute an Event of

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Default under the Credit Agreement exists, and (c) no condition, event, act or
omission has occurred, which, with the giving of notice or passage of time,
would constitute an Event of Default under the Credit Agreement.

     Section 4.02 The Borrower agrees to pay all fees and out-of-pocket
disbursements incurred by the Lender in connection with this Amendment,
including legal fees incurred by the Lender in the preparation, consummation,
administration and enforcement of this Amendment.

     Section 4.03 This Amendment is a modification only and not a novation.
Except for the above-quoted modification(s), the Credit Agreement, any agreement
or security document, and all the terms and conditions thereof, shall be and
remain in full force and effect with the changes herein deemed to be
incorporated therein. This Amendment is to be considered attached to the Credit
Agreement and made a part thereof. This Amendment shall not release or affect
the liability of any guarantor, surety or endorser of the Credit Agreement or
release any owner of collateral securing the Credit Agreement. The validity,
priority and enforceability of the Credit Agreement shall not be impaired
hereby. To the extent that any provision of this Amendment conflicts with any
term or condition set forth in the Credit Agreement, or any agreement or
security document executed in conjunction therewith, the provisions of this
Amendment shall supersede and control. Borrower acknowledges that as of the date
of this Amendment it has no offsets with respect to all amounts owed by Borrower
to Lender and Borrower waives and releases all claims which it may have against
Lender arising under the Credit Agreement on or prior to the date of this
Amendment.

     Section 4.05 The Borrower acknowledges and agrees that this Amendment is
limited to the terms outlined above, and shall not be construed as an amendment
of any other terms or provisions of the Credit Agreement; The Borrower hereby
specifically ratifies and affirms the terms and provisions of the Credit
Agreement. Borrower releases Lender from any and all claims which may have
arisen, known or unknown, in connection with the Credit Agreement on or prior to
the date hereof. This Amendment shall not establish a course of dealing or be
construed as evidence of any willingness on the Lender's part to grant other or
future amendments, should any be requested.

     IN WITNESS WHEREOF, the parties have entered into this Amendment as of the
day and year first above written.



LENDER:                                     BORROWER:

BANK ONE, TEXAS, N.A.                       IRI INTERNATIONAL CORPORATION

By: /s/ Karen S. Shouse                     By: /s/ Robert L. Hargrave
    ----------------------------                ----------------------------
        Karen S. Shouse
        First Vice President


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