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                                                                    EXHIBIT 10.8

                                    EXHIBIT B

                      FORM OF REGISTRATION RIGHTS AGREEMENT



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                          REGISTRATION RIGHTS AGREEMENT

      REGISTRATION RIGHTS AGREEMENT (this "Agreement"), dated as of June 1,
2000, between eMissions Testing, Inc., a Georgia corporation (the "Company"),
and GCA Strategic Investment Fund Limited (the "Fund") a Bermuda corporation.

      1. INTRODUCTION.

            1.1 SECURITIES PURCHASE AGREEMENT. The Company and the Fund has
today executed that certain Securities Purchase Agreement (the "Securities
Purchase Agreement"), pursuant to which the Company has agreed, among other
things, to issue up to an aggregate of One Million Dollars ($1,000,000.00)
(U.S.) principal amount of 7% Convertible Debentures of the Company (the
"Debentures") to the Fund or its successors, assigns or transferees
(collectively, the "Holders"). The Debentures are convertible into an
indeterminable number of shares (the "Debenture Conversion Shares") of the
Company's common stock, no par value per share (the "Common Stock") pursuant to
the terms of the Debentures. In addition, pursuant to the terms of the
Securities Purchase Agreement and the transactions contemplated thereby, the
Company has agreed to issue to the Fund Common Stock Purchase Warrants
exercisable for up to an aggregate of 500,000 shares of the Company's Common
Stock (the "Warrant Shares"). The number of Debenture Conversion Shares and
Warrant Shares is subject to adjustment upon the occurrence of stock splits,
recapitalizations and similar events occurring after the date hereof.

            1.2 DEFINITION OF SECURITIES. The Debenture Conversion Shares and
the Warrant Shares are herein referred to as the "Securities."

      2. REGISTRATION UNDER SECURITIES ACT, ETC.

            2.1 MANDATORY REGISTRATION.

                  (a) REGISTRATION OF REGISTRABLE SECURITIES. The Company shall
prepare and file within five (5) days following the date hereof a registration
statement (the "Registration Statement") covering the resale of the Registrable
Securities. The Company shall use its best efforts to cause the Registration
Statement to be declared effective by the Commission on the earlier of (i) 90
days following the date hereof with respect to the Registration Statement, (ii)
five (5) days following the receipt of a "No Review" or similar letter from the
Commission or (iii) the first day following the day the Commission determines
the Registration Statement eligible to be declared effective (the "Required
Effectiveness Date"). Nothing contained herein shall be deemed to limit the
number of Registrable Securities to be registered by the Company hereunder. As a
result, should the Registration Statement not relate to the maximum number of
Registrable Securities acquired by (or potentially acquirable by) the holders
thereof upon conversion of the Debentures, or exercise of the Common Stock
Purchase Warrants described in Section 1 above, the Company shall be required to
promptly file a separate registration statement (utilizing Rule 462 promulgated
under the Exchange Act, where applicable) relating to such Registrable
Securities which then remain unregistered. The


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provisions of this Agreement shall relate to any such separate registration
statement as if it were an amendment to the Registration Statement.

                  (b) REGISTRATION STATEMENT FORM. Registrations under this
Section 2.1 shall be on Form S-1 or such other appropriate registration form of
the Commission as shall permit the disposition of such Registrable Securities in
accordance with the intended method or methods of disposition specified by the
Fund; provided, however, such intended method of disposition shall not include
an underwritten offering of the Registrable Securities.

                  (c) EXPENSES. The Company will pay all Registration Expenses
in connection with any registration required by this Section 2.1.

                  (d) EFFECTIVE REGISTRATION STATEMENT. A registration requested
pursuant to this Section 2.1 shall not be deemed to have been effected (i)
unless a registration statement with respect thereto has become effective within
the time period specified herein, provided that a registration which does not
become effective after the Company filed a registration statement with respect
thereto solely by reason of the refusal to proceed of any holder of Registrable
Securities (other than a refusal to proceed based upon the advice of counsel in
the form of a letter signed by such counsel and provided to the Company relating
to a disclosure matter unrelated to such holder) shall be deemed to have been
effected by the Company unless the holders of the Registrable Securities shall
have elected to pay all Registration Expenses in connection with such
registration, (ii) if, after it has become effective, such registration becomes
subject to any stop order, injunction or other order or extraordinary
requirement of the Commission or other governmental agency or court for any
reason or (iii) if, after it has become effective, such registration ceases to
be effective for more than an aggregate of twenty (20) days.

                  (e) PLAN OF DISTRIBUTION. The Company hereby agrees that the
Registration Statement shall include a plan of distribution section reasonably
acceptable to the Fund; provided, however, such plan of distribution section
shall be modified by the Company so as to not provide for the disposition of the
Registrable Securities on the basis of an underwritten offering.

            2.2 INCIDENTAL REGISTRATION.

                  (A) RIGHT TO INCLUDE REGISTRABLE SECURITIES. If at any time
after the date hereof but before the third anniversary of the date hereof, the
Company proposes to register any of its securities under the Securities Act
(other than by a registration in connection with an acquisition in a manner
which would not permit registration of Registrable Securities for sale to the
public, on Form S-8, or any successor form thereto, on Form S-4, or any
successor form thereto and other than pursuant to Section 2.1), on an
underwritten basis (either best-efforts or firm-commitment), then, the Company
will each such time give prompt written notice to all Holders of its intention
to do so and of such Holders' rights under this Section 2.2. Upon the written
request of any such Holder made within twenty (20) days after the receipt of any
such notice (which request shall specify the Registrable Securities intended to
be disposed of by such


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Holder and the intended method of disposition thereof), the Company will,
subject to the terms of this Agreement, use its commercially reasonable best
efforts to effect the registration under the Securities Act of the Registrable
Securities, to the extent requisite to permit the disposition (in accordance
with the intended methods thereof as aforesaid) of such Registrable Securities
so to be registered, by inclusion of such Registrable Securities in the
registration statement which covers the securities which the Company proposes to
register, provided that if, at any time after written notice of its intention to
register any securities and prior to the effective date of the registration
statement filed in connection with such registration, the Company shall
determine for any reason either not to register or to delay registration of such
securities, the Company may, at its election, give written notice of such
determination to each Holder and, thereupon, (i) in the case of a determination
not to register, shall be relieved of this obligation to register any
Registrable Securities in connection with such registration (but not from its
obligation to pay the Registration Expenses in connection therewith), without
prejudice, however, to the rights of any holder or holders of Registrable
Securities entitled to do so to request that such registration be effected as a
registration under Section 2.1, and (ii) in the case of a determination to delay
registering, shall be permitted to delay registering any Registrable Securities,
for the same period as the delay in registering such other securities. No
registration effected under this Section 2.2 shall relieve the Company of its
obligation to effect any registration upon request under Section 2.1, nor shall
any such registration hereunder be deemed to have been effected pursuant to
Section 2.1. The Company will pay all Registration Expenses in connection with
each registration of Registrable Securities requested pursuant to this Section
2.2. The right provided the Holders of the Registrable Securities pursuant to
this Section shall be exercisable at their sole discretion and will in no way
limit any of the Company's obligations to pay the Securities according to their
terms.

                  (b) PRIORITY IN INCIDENTAL REGISTRATIONS. If the managing
underwriter of the underwritten offering contemplated by this Section 2.2 shall
inform the Company and holders of the Registrable Securities requesting such
registration by letter of its belief that the number of securities requested to
be included in such registration exceeds the number which can be sold in such
offering, then the Company will include in such registration, to the extent of
the number which the Company is so advised can be sold in such offering, (i)
first securities proposed by the Company to be sold for its own account, and
(ii) second Registrable Securities and securities of other selling security
holders requested to be included in such registration pro rata on the basis of
the number of shares of such securities so proposed to be sold and so requested
to be included; provided, however, the holders of Registrable Securities shall
have priority to all shares sought to be included by officers and directors of
the Company as well as holders of ten percent (10%) or more of the Company's
Common Stock.

            2.3 REGISTRATION PROCEDURES. If and whenever the Company is required
to effect the registration of any Registrable Securities under the Securities
Act as provided in Section 2.1 and, as applicable, 2.2, the Company shall, as
expeditiously as possible:

                  (i) prepare and file with the Commission the Registration
Statement, or amendments thereto, to effect such registration (including such
audited financial statements as may be required by the Securities Act or the
rules and regulations promulgated thereunder) and


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thereafter use its commercially reasonable best efforts to cause such
registration statement to be declared effective by the Commission, as soon as
practicable, but in any event no later than the Required Effectiveness Date
(with respect to a registration pursuant to Section 2.1); provided, however,
that before filing such registration statement or any amendments thereto, the
Company will furnish to the counsel selected by the holders of Registrable
Securities which are to be included in such registration, copies of all such
documents proposed to be filed;

                  (ii) with respect to any registration statement pursuant to
Section 2.1, prepare and file with the Commission such amendments and
supplements to such registration statement and the Prospectus used in connection
therewith as may be necessary to keep such registration statement effective and
to comply with the provisions of the Securities Act with respect to the
disposition of all Registrable Securities covered by such registration statement
until the earlier to occur of six (6) years after the date of this
Agreement(subject to the right of the Company to suspend the effectiveness
thereof for not more than 10 consecutive days or an aggregate of 30 days in such
six (6) years period) or such time as all of the securities which are the
subject of such registration statement cease to be Registrable Securities (such
period, in each case, the "Registration Maintenance Period");

                  (iii) furnish to each seller of Registrable Securities covered
by such registration statement such number of conformed copies of such
registration statement and of each such amendment and supplement thereto (in
each case including all exhibits), such number of copies of the Prospectus
contained in such registration statement (including each preliminary Prospectus
and any summary Prospectus) and any other Prospectus filed under Rule 424 under
the Securities Act, in conformity with the requirements of the Securities Act,
and such other documents, as such seller and underwriter, if any, may reasonably
request in order to facilitate the public sale or other disposition of the
Registrable Securities owned by such seller;

                  (iv) use its commercially reasonable best efforts to register
or qualify all Registrable Securities and other securities covered by such
registration statement under such other securities laws or blue sky laws as any
seller thereof shall reasonably request, to keep such registrations or
qualifications in effect for so long as such registration statement remains in
effect, and take any other action which may be reasonably necessary to enable
such seller to consummate the disposition in such jurisdictions of the
securities owned by such seller, except that the Company shall not for any such
purpose be required to qualify generally to do business as a foreign corporation
in any jurisdiction wherein it would not but for the requirements of this
subdivision (iv) be obligated to be so qualified or to consent to general
service of process in any such jurisdiction;

                  (v) use its commercially reasonable best efforts to cause all
Registrable Securities covered by such registration statement to be registered
with or approved by such other governmental agencies or authorities as may be
necessary to enable the seller or sellers thereof to consummate the disposition
of such Registrable Securities;

                  (vi) furnish to each seller of Registrable Securities a signed
counterpart, addressed to such seller, and the underwriters, if any, of:


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                        (A) an opinion of counsel for the Company, dated the
effective date of such registration statement (or, if such registration includes
an underwritten public offering, an opinion dated the date of the closing under
the underwriting agreement),reasonably satisfactory in form and substance to
such seller) including that the Prospectus and any Prospectus supplement forming
a part of the Registration Statement does not contain an untrue statement of a
material fact or omits a material fact required to be stated therein or
necessary in order to make the statements therein, in light of the circumstances
under which they were made, not misleading, and

                        (B) a "comfort" letter (or, in the case of any Person
which does not satisfy the conditions for receipt of a "comfort" letter
specified in Statement on Auditing Standards No. 72, an "agreed upon procedures"
letter), dated the effective date of such registration statement (and, if such
registration includes an underwritten public offering, a letter of like kind
dated the date of the closing under the underwriting agreement), signed by the
independent public accountants who have certified the Company's financial
statement included in such registration statement, covering substantially the
same matters with respect to such registration statement (and the Prospectus
included therein) and, in the case of the accountants' letter, with respect to
events subsequent to the date of such financial statements, as are customarily
covered in opinions of issuer's counsel and in accountants' letters delivered to
the underwriters in underwritten public offerings of securities (with, in the
case of an "agreed upon procedures" letter, such modifications or deletions as
may be required under Statement on Auditing Standards No. 35) and, in the case
of the accountants' letter, such other financial matters, and, in the case of
the legal opinion, such other legal matters, as such seller (or the
underwriters, if any) may reasonably request;

                  (vii) notify the Sellers' Representative and its counsel
promptly and confirm such advice in writing promptly after the Company has
knowledge thereof:

                        (A) when the Registration Statement, the Prospectus or
any Prospectus supplement related thereto or post-effective amendment to the
Registration Statement has been filed, and, with respect to the Registration
Statement or any post-effective amendment thereto, when the same has become
effective;

                        (B) of any request by the Commission for amendments or
supplements to the Registration Statement or the Prospectus or for additional
information;

                        (C) of  the issuance by the Commission of any stop order
suspending the effectiveness of the Registration Statement or the initiation of
any proceedings by any Person for that purpose; and

                        (D) of the receipt by the Company of any notification
with respect to the suspension of the qualification of any Registrable
Securities for sale under the securities or blue sky laws of any jurisdiction or
the initiation or threat of any proceeding for such purpose;


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                  (viii) notify each seller of Registrable Securities covered by
such registration statement, at any time when a Prospectus relating thereto is
required to be delivered under the Securities Act, upon discovery that, or upon
the happening of any event as a result of which, the Prospectus included in such
registration statement, as then in effect, includes an untrue statement of a
material fact or omits to state any material facts required to be stated therein
or necessary to make the statements therein not misleading in the light of the
circumstances then existing, and at the request of any such seller promptly
prepare and furnish to such seller a reasonable number of copies of a supplement
to or an amendment of such Prospectus as may be necessary so that, as thereafter
delivered to the purchasers of such securities, such Prospectus shall not
include an untrue statement of a material fact or omit to state a material fact
required to be stated therein or necessary to make the statements therein not
misleading in the light of the circumstances then existing;

                  (ix) use its best efforts to obtain the withdrawal of any
order suspending the effectiveness of the Registration Statement at the earliest
possible moment;

                  (x) otherwise use its commercially reasonable best efforts to
comply with all applicable rules and regulations of the Commission, and make
available to its security holders, as soon as reasonably practicable, an
earnings statement covering the period of at least twelve months, but not more
than eighteen months, beginning with the first full calendar month after the
effective date of such registration statement, which earnings statement shall
satisfy the provisions of Section 11(a) of the Securities Act and Rule 158
thereunder;

                  (xi) enter into such agreements and take such other actions as
the Sellers' Representative shall reasonably request in writing (at the expense
of the requesting or benefiting sellers) in order to expedite or facilitate the
disposition of such Registrable Securities; and

                  (xii) use its commercially reasonable best efforts to list all
Registrable Securities covered by such registration statement on any securities
exchange on which any of the Registrable Securities are then listed.

      The Company may require each seller of Registrable Securities as to which
any registration is being effected to furnish the Company such information
regarding such seller and the distribution of such securities as the Company may
from time to time reasonably request in writing.

      The Company will not file any registration statement pursuant to Section
2.1, or amendment thereto or any Prospectus or any supplement thereto (including
such documents incorporated by reference and proposed to be filed after the
initial filing of the Registration Statement) to which the Sellers'
Representative shall reasonably object, provided that the Company may file such
documents in a form required by law or upon the advice of its counsel.


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      The Company represents and warrants to each holder of Registrable
Securities that it has obtained all necessary waivers, consents and
authorizations necessary to execute this Agreement and consummate the
transactions contemplated hereby other than such waivers, consents and/or
authorizations specifically contemplated by the Securities Purchase Agreement.

      Each Fund agrees that, upon receipt of any notice from the Company of the
occurrence of any event of the kind described in subdivision (viii) of this
Section 2.3, such Fund will forthwith discontinue such Fund's disposition of
Registrable Securities pursuant to the Registration Statement relating to such
Registrable Securities until such Fund's receipt of the copies of the
supplemented or amended Prospectus contemplated by subdivision (viii) of this
Section 2.3 and, if so directed by the Company, will deliver to the Company (at
the Company's expense) all copies, other than permanent file copies, then in
such Fund's possession of the Prospectus relating to such Registrable Securities
current at the time of receipt of such notice.

            2.4 UNDERWRITTEN OFFERINGS.

                  (a) INCIDENTAL UNDERWRITTEN OFFERINGS. If the Company at any
time proposes to register any of its securities under the Securities Act as
contemplated by Section 2.2 and such securities are to be distributed by or
through one or more underwriters, the Company will, if requested by any holder
of Registrable Securities as provided in Section 2.2 and subject to the
provisions of Section 2.2(a), use its commercially reasonable best efforts to
arrange for such underwriters to include all the Registrable Securities to be
offered and sold by such holder among the securities to be distributed by such
underwriters.

                  (b) HOLDBACK AGREEMENTS. Subject to such other reasonable
requirements as may be imposed by the underwriter as a condition of inclusion of
a Fund's Registrable Securities in the registration statement, each Fund agrees
by acquisition of Registrable Securities, if so required by the managing
underwriter, not to sell, make any short sale of, loan, grant any option for the
purchase of, effect any public sale or distribution of or otherwise dispose of,
except as part of such underwritten registration, any equity securities of the
Company, during such reasonable period of time requested by the underwriter;
provided however, such period shall not exceed the 120 day period commencing 30
days prior to the commencement of such underwritten offering and ending 90 days
following the completion of such underwritten offering.

                  (c) PARTICIPATION IN UNDERWRITTEN OFFERINGS. No holder of
Registrable Securities may participate in any underwritten offering under
Section 2.2 unless such holder of Registrable Securities (i) agrees to sell such
Person's securities on the basis provided in any underwriting arrangements
approved, subject to the terms and conditions hereof, by the holders of a
majority of Registrable Securities to be included in such underwritten offering
and (ii) completes and executes all questionnaires, indemnities, underwriting
agreements and other documents (other than powers of attorney) required under
the terms of such underwriting arrangements. Notwithstanding the foregoing, no
underwriting agreement (or other agreement in connection with such offering)
shall require any holder of Registrable Securities to make an representations or
warranties to or agreements with the Company or the underwriters other than


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representations and warranties contained in a writing furnished by such holder
expressly for use in the related registration statement or representations,
warranties or agreements regarding such holder, such holder's Registrable
Securities and such holder's intended method of distribution and any other
representation required by law.

            2.5 PREPARATION; REASONABLE INVESTIGATION. In connection with the
preparation and filing of each registration statement under the Securities Act
pursuant to this Agreement, the Company will give the holders of Registrable
Securities registered under such registration statement, and their respective
counsel and accountants, the opportunity to participate in the preparation of
such registration statement, each Prospectus included therein or filed with the
Commission, and each amendment thereof or supplement thereto, and will give each
of them such access to its books and records and such opportunities to discuss
the business of the Company with its officers and the independent public
accountants who have certified its financial statements as shall be necessary,
in the reasonable opinion of such holders' and such underwriters' respective
counsel, to conduct a reasonable investigation within the meaning of the
Securities Act.

            2.6 REGISTRATION DEFAULT FEE. If the Registration Statement
contemplated in Section 2.1 is (x) not declared effective by the Required
Effectiveness Date or (y) such effectiveness is not maintained for the
Registration Maintenance Period, then the Company shall pay to the Fund the
Default Fee specified in Section 10.4 of the Securities Purchase Agreement.


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            2.7 INDEMNIFICATION.

                  (a) INDEMNIFICATION BY THE COMPANY. In the event of any
registration of any securities of the Company under the Securities Act, the
Company will, and hereby does agree to indemnify and hold harmless the holder of
any Registrable Securities covered by such registration statement, its directors
and officers, each other Person who participates as an underwriter in the
offering or sale of such securities and each other Person, if any, who controls
such holder or any such underwriter within the meaning of the Securities Act
against any losses, claims, damages or liabilities, joint or several, to which
such holder or any such director or officer or underwriter or controlling person
may become subject under the Securities Act or otherwise, insofar as such
losses, claims, damages or liabilities (or actions or proceedings, whether
commenced or threatened, in respect thereof) arise out of or are based upon any
untrue statement or alleged untrue statement of any material fact contained in
any registration statement under which such securities were registered under the
Securities Act, any preliminary Prospectus, final Prospectus or summary
Prospectus contained therein, or any amendment or supplement thereto, or any
omission or alleged omission to state therein a material fact required to be
stated therein or necessary to make the statements therein not misleading, and
the Company will reimburse such holder and each such director, officer,
underwriter and controlling person for any legal or any other expenses
reasonably incurred by them in connection with investigating or defending any
such loss, claim, liability, action or proceeding, provided that the Company
shall not be liable in any such case to the extent that any such loss, claim,
damage, liability, (or action or proceeding in respect thereof) or expense
arises out of or is based upon an untrue statement or alleged untrue statement
or omission or alleged omission made in such registration statement, any such
preliminary Prospectus, final Prospectus, summary Prospectus, amendment or
supplement in reliance upon and in conformity with written information furnished
to the Company by such holder or underwriter stating that it is for use in the
preparation thereof and, provided further that the Company shall not be liable
to any Person who participates as an underwriter in the offering or sale of
Registrable Securities or to any other Person, if any, who controls such
underwriter within the meaning of the Securities Act, in any such case to the
extent that any such loss, claim, damage, liability (or action or proceeding in
respect thereof) or expense arises out of such Person's failure to send or give
a copy of the final Prospectus, as the same may be then supplemented or amended,
within the time required by the Securities Act to the Person asserting the
existence of an untrue statement or alleged untrue statement or omission or
alleged omission at or prior to the written confirmation of the sale of
Registrable Securities to such Person if such statement or omission was
corrected in such final Prospectus or an amendment or supplement thereto. Such
indemnity shall remain in full force and effect regardless of any investigation
made by or on behalf of such holder or any such director, officer, underwriter
or controlling person and shall survive the transfer of such securities by such
holder.

                  (b) INDEMNIFICATION BY THE SELLERS. The Company may require,
as a condition to including any Registrable Securities in any registration
statement filed pursuant to this Agreement, that the Company shall have received
an undertaking satisfactory to it from the prospective seller of such
Registrable Securities, to indemnify and hold harmless (in the same manner and
to the same extent as set forth in subdivision (a) of this Section 2.7) the
Company, each director of the Company, each officer of the Company and each
other Person, if any, who


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controls the Company within the meaning of the Securities Act, with respect to
any statement or alleged statement in or omission or alleged omission from such
registration statement, any preliminary Prospectus, final Prospectus or summary
Prospectus contained therein, or any amendment or supplement thereto, if such
statement or alleged statement or omission or alleged omission was made in
reliance upon and in conformity with written information furnished to the
Company through an instrument duly executed by such seller specifically stating
that it is for use in the preparation of such registration statement,
preliminary Prospectus, final Prospectus, summary Prospectus, amendment or
supplement. Any such indemnity shall remain in full force and effect, regardless
of any investigation made by or on behalf of the Company or any such director,
officer or controlling person and shall survive the transfer of such securities
by such seller.

                  (c) NOTICES OF CLAIMS, ETC. Promptly after receipt by an
indemnified party of notice of the commencement of any action or proceeding
involving a claim referred to in the preceding subdivisions of this Section 2.7,
such indemnified party will, if a claim in respect thereof is to be made against
an indemnifying party, give written notice to the latter of the commencement of
such action, provided that the failure of any indemnified party to give notice
as provided herein shall not relieve the indemnifying party of its obligations
under the preceding subdivisions of this Section 2.7, except to the extent that
the indemnifying party is actually prejudiced by such failure to give notice. In
case any such action is brought against an indemnified party, unless in such
indemnified party's reasonable judgment a conflict of interest between such
indemnified and indemnifying parties may exist in respect of such claim, the
indemnifying party shall be entitled to participate in and to assume the defense
thereof, jointly with any other indemnifying party similarly notified, to the
extent that the indemnifying party may wish, with counsel reasonably
satisfactory to such indemnified party, and after notice from the indemnifying
party to such indemnified party of its election so to assume the defense
thereof, the indemnifying party shall not be liable to such indemnified party
for any legal or other expenses subsequently incurred by the latter in
connection with the defense thereof other than reasonable costs of
investigation. No indemnifying party shall, without the consent of the
indemnified party, consent to entry of any judgment or enter into any settlement
of any such action which does not include as an unconditional term thereof the
giving by the claimant or plaintiff to such indemnified party of a release from
all liability, or a covenant not to sue, in respect to such claim or litigation.
No indemnified party shall consent to entry of any judgment or enter into any
settlement of any such action the defense of which has been assumed by an
indemnifying party without the consent of such indemnifying party.

                  (d) OTHER INDEMNIFICATION. Indemnification similar to that
specified in the preceding subdivisions of this Section 2.7 (with appropriate
modifications) shall be given by the Company and each seller of Registrable
Securities (but only if and to the extent required pursuant to the terms of
Section 2.7(b)) with respect to any required registration or other qualification
of securities under any Federal or state law or regulation of any governmental
authority, other than the Securities Act.

                  (e) INDEMNIFICATION PAYMENTS. The indemnification required by
this Section 2.7 shall be made by periodic payments of the amount thereof during
the course of the


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investigation or defense, as and when bills are received or expense, loss,
damage or liability is incurred.

                  (f) CONTRIBUTION. If the indemnification provided for in the
preceding subdivision of this Section 2.7 is unavailable to an indemnified party
in respect of any expense, loss, claim, damage or liability referred to therein,
then each indemnifying party, in lieu of indemnifying such indemnified party,
shall contribute to the amount paid or payable by such indemnified party as a
result of such expense, loss, claim, damage or liability (i) in such proportion
as is appropriate to reflect the relative benefits received by the Company on
the one hand and the holder or underwriter, as the case may be, on the other
from the distribution of the Registrable Securities or (ii) if the allocation
provided by clause (i) above is not permitted by applicable law, in such
proportion as is appropriate to reflect not only the relative benefits referred
to in clause (i) above but also the relative fault of the Company on the one
hand and of the holder or underwriter, as the case may be, on the other in
connection with the statements or omissions which resulted in such expense,
loss, damage or liability, as well as any other relevant equitable
considerations. The relative benefits received by the Company on the one hand
and the holder or underwriter, as the case may be, on the other in connection
with the distribution of the Registrable Securities shall be deemed to be in the
same proportion as the total net proceeds received by the Company from the
initial sale of the Registrable Securities by the Company to the purchasers bear
to the gain, if any, realized by all selling holders participating in such
offering or the underwriting discounts and commissions received by the
underwriter, as the case may be. The relative fault of the Company on the one
hand and of the holder or underwriter, as the case may be, on the other shall be
determined by reference to, among other things, whether the untrue or alleged
untrue statement of a material fact or omission to state a material fact relates
to information supplied by the Company, by the holder or by the underwriter and
the parties' relative intent, knowledge, access to information supplied by the
Company, by the holder or by the underwriter and the parties' relative intent,
knowledge, access to information and opportunity to correct or prevent such
statement or omission, provided that the foregoing contribution agreement shall
not inure to the benefit of any indemnified party if indemnification would be
unavailable to such indemnified party by reason of the provisions contained in
the first sentence of subdivision (a) of this Section 2.7, and in no event shall
the obligation of any indemnifying party to contribute under this subdivision
(f) exceed the amount that such indemnifying party would have been obligated to
pay by way of indemnification if the indemnification provided for under
subdivisions (b) of this Section 2.7 had been available under the circumstances.

      The Company and the holders of Registrable Securities agree that it would
not be just and equitable if contribution pursuant to this subdivision (f) were
determined by pro rata allocation (even if the holders and any underwriters were
treated as one entity for such purpose) or by any other method of allocation
that does not take account of the equitable considerations referred to in the
immediately preceding paragraph. The amount paid or payable by an indemnified
party as a result of the losses, claims, damages and liabilities referred to in
the immediately preceding paragraph shall be deemed to include, subject to the
limitations set forth in the preceding sentence and subdivision (c) of this
Section 2.7, any legal or other expenses reasonably incurred


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by such indemnified party in connection with investigating or defending any such
action or claim.

      Notwithstanding the provisions of this subdivision (f), no holder of
Registrable Securities or underwriter shall be required to contribute any amount
in excess of the amount by which (i) in the case of any such holder, the net
proceeds received by such holder from the sale of Registrable Securities or (ii)
in the case of an underwriter, the total price at which the Registrable
Securities purchased by it and distributed to the public were offered to the
public exceeds, in any such case, the amount of any damages that such holder or
underwriter has otherwise been required to pay by reason of such untrue or
alleged untrue statement or omission. No Person guilty of fraudulent
misrepresentation (within the meaning of Section 11(f) of the Securities Act)
shall be entitled to contribution from any person who was not guilty of such
fraudulent misrepresentation.

      3. DEFINITIONS. As used herein, unless the context otherwise requires, the
following terms have the following respective meanings:

            "AGREEMENT": As defined in Section 1.

            "COMMISSION": The Securities and Exchange Commission or any other
Federal agency at the time administering the Securities Act.

            "COMMON STOCK": As defined in Section 1.

            "COMPANY": As defined in the introductory paragraph of this
Agreement.

            "CONVERSION SHARES": As defined in Section 1.

            "DEBENTURES": As defined in Section 1, such term to include any
securities issued in substitution of or in addition to such Debentures.

            "EXCHANGE ACT": The Securities Exchange Act of 1934, as amended, and
the rules and regulations of the Commission thereunder.

            "OTC BULLETIN BOARD": As defined in Section 1.

            "PERSON": A corporation, association, partnership, organization,
business,individual, governmental or political subdivision thereof or a
governmental agency.

            "REGISTRABLE SECURITIES": The Securities and any securities issued
or issuable with respect to such Securities by way of stock dividend or stock
split or in connection with a combination of shares, recapitalization, merger,
consolidation or other reorganization or otherwise. Once issued such securities
shall cease to be Registrable Securities when (a) a registration statement with
respect to the sale of such securities shall have become effective under the
Securities Act and such securities shall have been disposed of in accordance
with such registration statement, (b) they shall have been distributed to the
public pursuant to Rule 144 (or


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any successor provision) under the Securities Act, (c) they shall have been
otherwise transferred, new certificates for them not bearing a legend
restricting further transfer shall have been delivered by the Company and
subsequent disposition of them shall not require registration or qualification
of them under the Securities Act or any similar state law then in force, (d)
they shall have ceased to be outstanding, (e) on the expiration of the
applicable Registration Maintenance Period or (f) any and all legends
restricting transfer thereof have been removed in accordance with the provisions
of Rule 144(k) (or any successor provision) under the Securities Act.

            "REGISTRATION EXPENSES": All expenses incident to the Company's
performance of or compliance with this Agreement, including, without limitation,
all registration, filing and NASD fees, all stock exchange and OTC Bulletin
Board or other NASD or stock exchange listing fees, all fees and expenses of
complying with securities or blue sky laws, all word processing, duplicating and
printing expenses, messenger and delivery expenses, the fees and disbursements
of counsel for the Company and of its independent public accountants, including
the expenses of any special audits or "cold comfort" letters required by or
incident to such performance and compliance, the reasonable fees and
disbursements of not more than one law firm (not to exceed $20,000) retained by
the holder or holders of more than 50% of the Registrable Securities, premiums
and other costs of policies of insurance of the Company against liabilities
arising out of the public offering of the Registrable Securities being
registered and any fees and disbursements of underwriters customarily paid by
issuers or sellers of securities, but excluding underwriting discounts and
commissions and transfer taxes, if any, provided that, in any case where
Registration Expenses are not to be borne by the Company, such expenses shall
not include salaries of Company personnel or general overhead expenses of the
Company, auditing fees, premiums or other expenses relating to liability
insurance required by underwriters of the Company or other expenses for the
preparation of financial statements or other data normally prepared by the
Company in the ordinary course of its business or which the Company would have
incurred in any event.

            "REGISTRATION MAINTENANCE PERIOD": As defined in Section 2.3.

            "REQUIRED EFFECTIVENESS DATE": As defined in Section 2.1.

            "SECURITIES ACT": The Securities Act of 1933, as amended, and the
rules and regulations of the Commission thereunder.

            "SECURITIES PURCHASE AGREEMENT": As defined in Section 1.

            "SELLERS' REPRESENTATIVE": Global Capital Advisors Ltd. or such
Person designated by Global Capital Advisors Ltd. as of the time of disposition
of the last of the Debentures held by the Fund (or subsequent Sellers'
Representative).

            "WARRANT SHARES": As defined in Section 1.

      4. RULE 144. The Company shall timely file the reports required to be
filed by it under the Securities Act and the Exchange Act (including but not
limited to the reports under


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Sections 13 and 15(d) of the Exchange Act referred to in subparagraph (c) of
Rule 144 adopted by the Commission under the Securities Act) and the rules and
regulations adopted by the Commission thereunder (or, if the Company is not
required to file such reports, will, upon the request of any holder of
Registrable Securities, make publicly available other information) and will take
such further action as any holder of Registrable Securities may reasonably
request, all to the extent required from time to time to enable such holder to
sell Registrable Securities without registration under the Securities Act within
the limitation of the exemptions provided by (a) Rule 144 under the Securities
Act, as such Rule may be amended from time to time, or (b) any similar rule or
regulation hereafter adopted by the Commission. Upon the request of any holder
of Registrable Securities, the Company will deliver to such holder a written
statement as to whether it has complied with the requirements of this Section 4.

      5 AMENDMENTS AND WAIVERS. This Agreement may be amended and the Company
may take any action herein prohibited, or omit to perform any act herein
required to be performed by it, only if the Company shall have obtained the
written consent to such amendment, action or omission to act, of the holder or
holders of the sum of the 51% or more of the shares of (i) Registrable
Securities issued at such time, plus (ii) Registrable Securities issuable upon
exercise or conversion of the Securities then constituting derivative securities
(if such Securities were not fully exchanged or converted in full as of the date
such consent if sought). Each holder of any Registrable Securities at the time
or thereafter outstanding shall be bound by any consent authorized by this
Section 5, whether or not such Registrable Securities shall have been marked to
indicate such consent.

      6 NOMINEES FOR BENEFICIAL OWNERS. In the event that any Registrable
Securities are held by a nominee for the beneficial owner thereof, the
beneficial owner thereof may, at its election, be treated as the holder of such
Registrable Securities for purposes of any request or other action by any holder
or holders of Registrable Securities pursuant to this Agreement or any
determination of any number of percentage of shares of Registrable Securities
held by a holder or holders of Registrable Securities contemplated by this
Agreement. If the beneficial owner of any Registrable Securities so elects, the
Company may require assurances reasonably satisfactory to it of such owner's
beneficial ownership or such Registrable Securities.

      7 NOTICES. Except as otherwise provided in this Agreement, all notices,
requests and other communications to any Person provided for hereunder shall be
in writing and shall be given to such Person (a) in the case of a party hereto
other than the Company, addressed to such party in the manner set forth in the
Securities Purchase Agreement or at such other address as such party shall have
furnished to the Company in writing, or (b) in the case of any other holder of
Registrable Securities, at the address that such holder shall have furnished to
the Company in writing, or, until any such other holder so furnishes to the
Company an address, then to and at the address of the last holder of such
Registrable Securities who has furnished an address to the Company, or (c) in
the case of the Company, at the address set forth on the signature page hereto,
to the attention of its President, or at such other address, or to the attention
of such other officer, as the Company shall have furnished to each holder of
Registrable Securities at the time outstanding. Each such notice, request or
other communication shall be effective (i) if given by mail, 72 hours after such
communication is deposited in the mail with first class postage prepaid,


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addressed as aforesaid or (ii) if given by any other means (including, without
limitation, by fax or air courier), when delivered at the address specified
above, provided that any such notice, request or communication shall not be
effective until received.

      8 ASSIGNMENT. This Agreement shall be binding upon and inure to the
benefit of and be enforceable by the parties hereto. In addition, and whether or
not any express assignment shall have been made, the provisions of this
Agreement which are for the benefit of the parties hereto other than the Company
shall also be for the benefit of and enforceable by any subsequent holder of any
Registrable Securities. Each of the Holders of the Registrable Securities
agrees, by accepting any portion of the Registrable Securities after the date
hereof, to the provisions of this Agreement including, without limitation,
appointment of the Sellers' Representative to act on behalf of such Holder
pursuant to the terms hereof which such actions shall be made in the good faith
discretion of the Sellers' Representative and be binding on all persons for all
purposes.

      9 DESCRIPTIVE HEADINGS. The descriptive headings of the several sections
and paragraphs of this Agreement are inserted for reference only and shall not
limit or otherwise affect the meaning hereof.

      107 GOVERNING LAW. THIS AGREEMENT SHALL BE CONSTRUED AND ENFORCED IN
ACCORDANCE WITH, AND THE RIGHTS OF THE PARTIES SHALL BE GOVERNED BY, THE LAWS OF
THE STATE OF GEORGIA WITHOUT REFERENCE TO THE PRINCIPLES OF CONFLICTS OF LAWS.

      11 COUNTERPARTS. This Agreement may be executed by facsimile and may be
signed simultaneously in any number of counterparts, each of which shall be
deemed an original, but all such counterparts shall together constitute one and
the same instrument.

      12 ENTIRE AGREEMENT. This Agreement embodies the entire agreement and
understanding between the Company and each other party hereto relating to the
subject matter hereof and supercedes all prior agreements and understandings
relating to such subject matter.

      13 SEVERABILITY. If any provision of this Agreement, or the application of
such provisions to any Person or circumstance, shall be held invalid, the
remainder of this Agreement, or the application of such provision to Persons or
circumstances other than those to which it is held invalid, shall not be
affected thereby.


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      IN WITNESS WHEREOF, the parties have caused this Agreement to be executed
and delivered by their respective officers thereunto duly authorized as of the
date first above written.

                                        eMISSIONS TESTING, INC.


                                        By:
                                           -------------------------------------
                                        Name: William Estroff
                                        Title: President and Chief Executive
                                               Officer


                                        Address: 104 Colony Park Drive
                                                 Suite 600
                                                 Cumming, GA 30040

                                                 Fax:
                                                     ---------------------------
                                                 Tel.:
                                                      --------------------------


                                        GCA STRATEGIC INVESTMENT FUND LIMITED


                                        By:
                                           -------------------------------------
                                        Name: Lewis N. Lester
                                        Title: Director

                                        Address: c/o Prime Management Limited
                                                 Mechanics Building
                                                 12 Church Street
                                                 Hamilton HM-11, Bermuda

                                                 Fax: 441-295-3926
                                                 Tel.: 441-295-0329


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