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                           SYSTEMONE TECHNOLOGIES INC.

                                 PROMISSORY NOTE

$__________________                                             August 7, 2000
                                                              New York, New York

         SECTION 1. GENERAL. SYSTEMONE TECHNOLOGIES INC., a Florida corporation
(hereinafter referred to as the "Borrower"), with offices at 8305 N.W. 27th
Street, Miami, Florida 33122, for value received, hereby promises to pay to
_________________, or order, the principal amount of $______________, on the
Maturity Date (as defined in the Loan Agreement hereinafter described), in such
coin or currency of the United States of America as at the time of payment shall
be legal tender therein for the payment of public and private debts and to pay
interest on such principal amount at the rates and on the dates described in
Section 2.3 of the Loan Agreement hereinafter described. The Borrower further
agrees to pay interest at such rates described in Section 2.5 of the Loan
Agreement hereinafter described on any overdue principal and (to the extent
permitted by law) on any overdue interest, from the due date thereof until the
obligation of the Borrower with respect to the payment thereof shall be
discharged; all payments and prepayments of principal of this Note and all
payments of the interest on this Note to be made at ____________, or such other
location as shall be specified in writing by the holder of this Note to the
Borrower.

         SECTION 2. GOVERNING LAW. This Note shall be governed by and construed
in accordance with the laws of the State of New York applicable to agreements
made and to be performed entirely within such state.

         SECTION 3. RELATED AGREEMENTS. This Note is issued pursuant to, and is
one of the Notes referred to in, the Loan Agreement dated as of August 7, 2000
(herein referred to as the "Loan Agreement") among the Borrower, Hanseatic
Americas LDC, Environmental Opportunities Fund II, L.P. and Environmental
Opportunities Fund II (Institutional), L.P., and is entitled to the benefits and
is subject to the provisions thereof( including, without limitation, those
providing for the optional and mandatory prepayment of this Note and the
acceleration of the maturity hereof), and to the benefits of the Security
Agreement, dated the date hereof, among the Borrower, Hanseatic Americas LDC,
Environmental Opportunities Fund II, L.P. and Environmental Opportunities Fund
II (Institutional), L.P. Copies of such agreements may be obtained by any holder
of this Note at the principal executive offices of the Borrower.
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         SECTION 4. SUBORDINATION. THE RIGHTS AND REMEDIES OF THE HOLDER HEREOF
ARE SUBJECT TO AND SUBORDINATED TO THE TERMS AND PROVISIONS OF A SUBORDINATION
AGREEMENT, DATED OF EVEN DATE HEREOF, ENTERED INTO WITH CAPITAL BUSINESS CREDIT,
A DIVISION OF CAPITAL FACTORS, INC.

         IN WITNESS WHEREOF, the undersigned has executed this Note as of the
date first-above written.

ATTEST:                                SYSTEMONE TECHNOLOGIES INC.

                                       By
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