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                                                                  EXECUTION COPY

                         FOURTH AMENDMENT AND WAIVER TO
                       AMENDED AND RESTATED LOAN AGREEMENT

         THIS FOURTH AMENDMENT AND WAIVER TO AMENDED AND RESTATED LOAN
AGREEMENT (this "FOURTH AMENDMENT"), dated as of January 31, 2001, is among
QUIXOTE CORPORATION, a Delaware corporation ("QUIXOTE"), ENERGY ABSORPTION
SYSTEMS, INC., a Delaware corporation (f/k/a Quixote Laser Corporation and
successor by merger to Energy Absorption Systems, Inc., a Delaware
corporation and Roadway Safety Service, Inc., a Delaware corporation)
("EAS"), QUIXOTE TRANSPORTATION SAFETY, INC., a Delaware corporation (f/k/a
TranSafe Corporation) ("TRANSPORTATION"), SPIN-CAST PLASTICS, INC., an
Indiana corporation ("SPIN-CAST"), E-TECH TESTING SERVICES, INC., a Delaware
corporation ("E-Tech"), SAFE-HIT CORPORATION, a Nevada corporation
("SAFE-HIT"), HIGHWAY INFORMATION SYSTEMS, INC., a Delaware corporation
("HIS"), NU-METRICS, INC., a Pennsylvania corporation ("NU-METRICS"), QUIXOTE
TRANSPORTATION SAFETY (ASIA PACIFIC) PTY LIMITED (f/k/a Energy Absorption
Systems PTY Limited), an Australian corporation ("QTS AUSTRALIA"), QUIXOTE
TRANSPORTATION SAFETY (EUROPE), INC., a Delaware corporation ("QTS EUROPE"),
NATIONAL SIGNAL, INC., a California corporation ("NATIONAL SIGNAL"), ENERGY
ABSORPTION SYSTEMS (EUROPE), INC., a Delaware corporation ("EAS EUROPE"),
TRANSAFE CORPORATION, a Delaware corporation ("TRANSAFE") certain lenders
signatory hereto ("LENDERS"), and THE NORTHERN TRUST COMPANY, an Illinois
banking corporation, as agent for the Lenders hereunder ("AGENT"). Quixote,
EAS, Transportation, Spin-Cast, E-Tech, Safe-Hit, HIS, Nu-Metrics, EAS
Australia, EAS Europe and TranSafe are individually and collectively referred
to herein as "BORROWER." This Fourth Amendment shall amend that certain
Amended and Restated Loan Agreement dated as of June 30, 1997 among the
Borrower, the Lenders and the Agent, as previously amended by that certain
First Amendment to Revolving Credit Agreement dated as of May 31, 1998, that
certain Second Amendment and Waiver to Amended and Restated Loan Agreement
dated as of March 15, 1999 and that certain Third Amendment and Waiver to
Amended and Restated Loan Agreement dated as of May 17, 2000 (as amended,
restated, modified or supplemented, the "LOAN AGREEMENT").

                                   WITNESSETH:

         WHEREAS, the Borrower, the Lenders and the Agent are parties to the
Loan Agreement;

         WHEREAS, Energy Absorption Systems PTY Limited, an Australian
corporation, and a Borrower hereunder changed its name to Quixote
Transportation Safety (Asia Pacific) PTY Limited, an Australian corporation;

         WHEREAS, on January 16, 2001, Transportation acquired all of the
outstanding capital stock of National Signal and National Signal became and
remains a wholly-owned Subsidiary of Transportation;

         WHEREAS, QTS Europe was newly incorporated as a Delaware corporation
and is a wholly-owned Subsidiary of EAS;

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         WHEREAS, each Borrower desires to make National Signal and QTS
Europe a Borrower under the Loan Agreement;

         WHEREAS, the Borrower has requested that the Agent and the Lenders
waive any Default or Event of Default under SECTION 7.3 of the Loan Agreement
arising out of the Borrower's assumption and immediate repayment of
Indebtedness in the amount of approximately $1,700,000 in connection with the
acquisition of National Signal, as described herein;

         WHEREAS, the Borrower has, among other amendments, requested an
extension of one year on the maturity dates for the Revolving Credit Loans,
the Conversion Date, and the Term Loans, and the Lenders and the Agent have
agreed to amend the Loan Agreement in this and other respects as set forth
herein;

         NOW, THEREFORE, the parties hereto hereby agree as follows:

1.       AMENDMENTS TO THE LOAN AGREEMENT.

         1.1      TERMS USED.  Terms used but not otherwise defined herein
are used with the same meanings as provided therefor in the Loan Agreement.

         1.2      SECTION 1.  SECTION 1 of the Loan Agreement is hereby
amended as of the date hereof by:

                  (a)      deleting the references to the dates "October 31,
                           2002" and "October 31, 2006" in the definition of
                           "Commitment Termination Date" and replacing them with
                           the dates "October 31, 2003" and "October 31, 2007"
                           respectively; and

                  (b)      deleting the reference to the date "November 1, 2002"
                           in the definition of "Conversion Date" and replacing
                           it with the date "November 1, 2003".

         1.3      SECTION 7.3.  SECTION 7.3 of the Loan Agreement is hereby
amended by deleting the "." at the end thereof and replacing it with the
following:

                  "; and (xv) Indebtedness under that certain Promissory Note
                  dated January 16, 2001 in the original principal amount of
                  $900,000 by Quixote Transportation Safety, Inc. in favor of
                  Mark Fernandez and Indebtedness under that certain Promissory
                  Note dated as of January 16, 2001 in the original principal
                  amount of $600,000 by Quixote Transportation Safety, Inc. in
                  favor of Guadalupe Martinez."

         1.4 EXHIBITS. EXHIBITS A, B, C and E to the Loan Agreement are
deleted in their entirety and EXHIBITS A, B, C and E attached hereto are
substituted in lieu thereof.

         1.5 DEFINITION OF "BORROWER". The parties hereto hereby agree that
National Signal and QTS Europe will henceforth each individually be a
"Borrower" under the Loan Agreement and, together with Quixote, EAS,
Transportation, Spin-Cast, E-Tech, Safe-Hit, HIS, Nu-Metrics,

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QTS Australia, EAS Europe and TranSafe, shall collectively henceforth be the
"Borrower" under the terms of the Loan Agreement. The definition of
"Borrower" set forth in the preamble to the Loan Agreement is hereby amended
to mean the entities, individually and collectively, set forth in this
SECTION 1.5.

         1.6 SCHEDULE 1. SCHEDULE 1 is attached hereto and made a part hereof
and a part of the Loan Agreement. The Borrower has included the information
set forth in SCHEDULE 1 in order to amend and supplement the information
provided by the Borrower on the Closing Date in the various schedules to the
Loan Agreement and in order to make the information contained therein
accurate and complete as of the date hereof.

2.       WAIVER.

         The Agent and the Required Lenders hereby waive any Default or Event
of Default under SECTION 7.3 of the Loan Agreement arising out of the
Borrower's assumption of Indebtedness in the amount of approximately
$1,700,000 in connection with the acquisition of National Signal, which
Indebtedness was immediately repaid in full on the closing date of such
acquisition. The waiver by the Agent and the Required Lenders as described
above shall not operate as a consent or waiver of (i) any other right, power
or remedy of the Agent or the Lenders under the Loan Documents, or (ii) any
other Default or Event of Default under the Loan Agreement. Such waiver is
only applicable and shall only be effective in the specific instance and for
the specific purpose for which made or given.

3.       REPRESENTATIONS AND WARRANTIES.

         The Borrower hereby remakes, as at the date of execution hereof, all
of the representations and warranties set forth in SECTION 4 of the Loan
Agreement as amended hereby and as amended and supplemented by SCHEDULE 1
hereto, and additionally represents and warrants that: (a) the borrowings
under the Loan Agreement as amended hereby, the execution and delivery by the
Borrower of this Fourth Amendment and the performance by the Borrower of its
obligations under this Fourth Amendment and the Loan Agreement as amended
hereby are within the Borrower's corporate powers, have been authorized by
all necessary corporate action, have received all necessary governmental
approval (if any shall be required) and do not and will not contravene or
conflict with any provision of law or of the charter or by-laws of the
Borrower or any subsidiary or of any agreement binding upon the Borrower or
any subsidiary; (b) no Default or Event of Default under the Loan Agreement
as amended hereby has occurred and is continuing on the date of execution
hereof; and (c) the information provided herein and in SCHEDULE 1 hereto with
respect to QTS Australia, National Signal and QTS Europe and with respect to
all other matters contained herein and therein, is true and complete in all
respects and fully and completely amends and supplements all of the schedules
provided by the Borrower pursuant to the Loan Agreement as necessary to make
the information contained in such schedules accurate and complete as of the
date hereof.

4.       CONDITIONS OF EFFECTIVENESS.

         The effectiveness of this Fourth Amendment is subject to the
conditions precedent that the Agent shall have received all of the following,
in form and substance satisfactory to the

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Agent and its counsel, at the expense of the Borrower, and, as appropriate,
dated as of the date hereof and in such number of signed counterparts as the
Agent may request:

         (a)      FOURTH AMENDMENT.  This Fourth Amendment;

         (b)      RESOLUTIONS/INCUMBENCY.  A certificate from the Secretary
                  or Assistant Secretary of each Borrower certifying (i) the
                  name(s) of the officer or officers of the Borrower authorized
                  to sign this Fourth Amendment and the other documents provided
                  for in this Fourth Amendment, together with a sample of the
                  true signature of each such officer (the Agent may
                  conclusively rely on each such certificate until formally
                  advised by a like certificate of any changes therein),  (ii)
                  true and correct copies of any resolutions of the Board of
                  Directors of each Borrower authorizing or ratifying the
                  execution, delivery and performance of this Fourth Amendment,
                  the Loan Agreement as amended hereby, the Amended and Restated
                  Revolving Credit Notes and other documents provided for in
                  this Fourth Amendment, (iii) for each of the certificates of
                  each Borrower other than QTS Australia, National Signal and
                  QTS Europe, there has been no change in the Certificate of
                  Incorporation or Bylaws for such Borrower since June 22, 2000
                  and such Certificate of Incorporation and Bylaws are in full
                  force and effect as of the date hereof and no steps have been
                  taken by the directors or stockholders of such Borrower to
                  effect or authorize any amendment or modification thereto;
                  and (iv) (A) for the certificate of QTS Australia, true and
                  correct copies of (1) the Certificate of Registration for QTS
                  Australia and all amendments thereto, as certified by the
                  Australian Securities and Investment Commission, and (2) the
                  Constitution of QTS Australia and (B) for the certificates of
                  National Signal and QTS Europe, true and correct copies of
                  (1) the Certificate of Incorporation of such corporation and
                  all amendments thereto, as certified by the secretary of state
                  of its jurisdiction of incorporation and (2) the Bylaws of
                  such corporation.

         (c)      NO DEFAULT - REPRESENTATIONS ACCURATE. A certificate
                  of each Borrower, dated the date hereof, that (i) no
                  Default or Event of Default has occurred and is
                  continuing and (ii) all representations and
                  warranties contained in the Loan Agreement as further
                  amended hereby and as amended and supplemented by the
                  information set forth in SCHEDULE 1 attached hereto,
                  are true and complete as of the date hereof;

         (d)      AMENDED AND RESTATED REVOLVING CREDIT NOTES. An
                  original Amended and Restated Revolving Credit Note
                  dated as of the date hereof in the form of EXHIBIT B
                  attached hereto in favor of each Lender and executed
                  by each Borrower as replacements for the Amended and
                  Restated Revolving Credit Notes executed and
                  delivered on May 17, 2000 pursuant to SECTION 2.1(b)
                  of the Loan Agreement;

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         (e)      GOOD STANDING CERTIFICATE.  A Good Standing Certificate for
                  QTS Australia from the Australian Securities and Investments
                  Commission and good standing certificates for each of QTS
                  Europe and National Signal from the secretary of state of
                  its jurisdiction of incorporation;

         (f)      LEGAL OPINION.  The opinion of Joan R. Riley, General
                  Counsel of Borrower, addressed to the Lenders and the
                  Agent in the form of EXHIBIT D attached hereto and made
                  a part hereof;

         (g)      ACCOUNTANT'S LETTER. A letter to PricewaterhouseCoopers,
                  LLP, the independent accountants for Borrower, in
                  form and substance satisfactory to Agent, executed by
                  the Borrower; and

         (h)      MISCELLANEOUS.  Such other documents as the Agent may request.

5.       MISCELLANEOUS.

         5.1 COUNTERPARTS. This Fourth Amendment may be executed by the
parties on any number of separate counterparts and by each party on separate
counterparts; each counterpart shall be deemed an original instrument; and
all of the counterparts taken together shall be deemed to constitute one and
the same instrument.

         5.2 EXHIBITS AND SCHEDULES. All exhibits and schedules attached
hereto are made a part hereof and incorporated herein as though fully set
forth herein.

         5.3 SUCCESSORS AND ASSIGNS. This Fourth Amendment and the Loan
Agreement as amended hereby shall be binding upon and inure to the benefit of
the Borrower, the Lenders, the Agent and their respective successors and
assigns.

         5.4 CAPTIONS. Captions in this Fourth Amendment are for convenience
of reference only and shall not define or limit any of the terms or
provisions hereof.

         5.5 FEES. The Borrower agrees to pay or reimburse the Agent for all
reasonable costs and expenses of preparing and seeking advice in regard to
this Fourth Amendment and any document or instrument executed in connection
herewith and therewith (including legal fees and reasonable time charges of
attorneys who may be employees of the Agent, whether in or out of court, in
original or appellate proceedings or in bankruptcy).

         5.6 CONSTRUCTION. THIS FOURTH AMENDMENT, THE LOAN AGREEMENT AS
AMENDED HEREBY AND ANY DOCUMENT OR INSTRUMENT EXECUTED IN CONNECTION HEREWITH
OR THEREWITH SHALL BE GOVERNED BY, AND CONSTRUED AND INTERPRETED IN
ACCORDANCE WITH, THE INTERNAL LAWS OF THE STATE OF ILLINOIS APPLICABLE TO
CONTRACTS MADE AND PERFORMED IN SUCH STATE, WITHOUT REGARD TO THE PRINCIPLES
THEREOF REGARDING CONFLICT OF LAWS, AND ANY APPLICABLE LAWS OF THE UNITED
STATES OF AMERICA. AGENT, EACH LENDER AND BORROWER AGREE TO SUBMIT TO
PERSONAL JURISDICTION AND TO WAIVE ANY OBJECTION AS TO VENUE IN THE COUNTY OF
COOK,

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STATE OF ILLINOIS. BORROWER AGREES NOTHING HEREIN SHALL PRECLUDE AGENT, ANY
LENDER OR BORROWER FROM BRINGING SUIT OR TAKING OTHER LEGAL ACTION IN ANY
OTHER JURISDICTION.

         5.7 MUTUAL WAIVER OF JURY TRIAL. BECAUSE DISPUTES ARISING IN
CONNECTION WITH COMPLEX FINANCIAL TRANSACTIONS ARE MOST QUICKLY AND
ECONOMICALLY RESOLVED BY AN EXPERIENCED AND EXPERT PERSON AND THE PARTIES
WISH APPLICABLE STATE AND FEDERAL LAWS TO APPLY (RATHER THAN ARBITRATION
RULES), THE PARTIES DESIRE THAT THEIR DISPUTES BE RESOLVED BY A JUDGE
APPLYING SUCH APPLICABLE LAWS. THEREFORE, TO ACHIEVE THE BEST COMBINATION OF
THE BENEFITS OF THE JUDICIAL SYSTEM AND OF ARBITRATION, THE PARTIES HERETO
WAIVE ALL RIGHT TO TRIAL BY JURY IN ANY ACTION, SUIT OR PROCEEDING BROUGHT TO
ENFORCE OR DEFEND ANY RIGHTS OR REMEDIES UNDER THIS FOURTH AMENDMENT, ANY OF
THE OTHER LOAN DOCUMENTS OR ANY OF THE OTHER AGREEMENTS.

         5.8 AMENDMENT TO LOAN AGREEMENT. This Fourth Amendment shall be
deemed to be an amendment to the Loan Agreement. All references to the Loan
Agreement in any other document or instrument shall be deemed to refer to the
Loan Agreement as amended hereby. As hereby amended, the Loan Agreement is
hereby ratified and confirmed in each and every respect.

                     [signature page to follow]

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         IN WITNESS WHEREOF, the parties hereto have caused this Fourth
Amendment to be executed by their duly authorized officers as of the day and
year first written above.


                                         THE NORTHERN TRUST COMPANY,
                                         as Agent and as Lender

                                         By:   /s/ Daniel A. Toll
                                            --------------------------------
                                         Name: Daniel A. Toll
                                         Title: Vice President


                                         LASALLE BANK NATIONAL ASSOCIATION,
                                         as Lender

                                         By:   /s/ Stephanie Patterson
                                            --------------------------------
                                         Name: Stephanie Patterson
                                         Title: Assistant Vice President


                                         AMERICAN NATIONAL BANK AND TRUST
                                         COMPANY OF CHICAGO, as Lender

                                         By:   /s/ Stacey J. Huels
                                            --------------------------------
                                         Name: Stacey J. Huels
                                         Title: First Vice President

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QUIXOTE CORPORATION                      ENERGY ABSORPTION SYSTEMS, INC.

By:  /s/ Daniel P. Gorey                 By:  /s/ Daniel P. Gorey
   -----------------------------            --------------------------------
Name: Daniel P. Gorey                    Name: Daniel P. Gorey
Title(s): Vice President and Treasurer   Title(s): Vice President and Treasurer


HIGHWAY INFORMATION SYSTEMS, INC.        NU-METRICS, INC.

By:  /s/ Daniel P. Gorey                 By:  /s/ Daniel P. Gorey
   -----------------------------            --------------------------------
Name: Daniel P. Gorey                    Name: Daniel P. Gorey
Title(s): Vice President and Treasurer   Title(s): Vice President and Treasurer


E-TECH TESTING SERVICES, INC.            SPIN-CAST PLASTICS, INC.

By:  /s/ Daniel P. Gorey                 By:  /s/ Daniel P. Gorey
   -----------------------------            --------------------------------
Name: Daniel P. Gorey                    Name: Daniel P. Gorey
Title(s): Vice President and Treasurer   Title(s): Vice President and Treasurer


ENERGY ABSORPTION SYSTEMS                SAFE-HIT CORPORATION
(EUROPE), INC.

By:  /s/ Daniel P. Gorey                 By:  /s/ Daniel P. Gorey
   -----------------------------            --------------------------------
Name: Daniel P. Gorey                    Name: Daniel P. Gorey
Title(s): Vice President and Treasurer   Title(s): Vice President and Treasurer


QUIXOTE TRANSPORTATION SAFETY, INC.      QUIXOTE TRANSPORTATION SAFETY (ASIA
                                         PACIFIC) PTY LIMITED

By:  /s/ Daniel P. Gorey                 By:  /s/ Daniel P. Gorey
   -----------------------------            --------------------------------
Name: Daniel P. Gorey                    Name:  Daniel P. Gorey
Title(s): Vice President and Treasurer   Title(s):  Vice President and Treasurer


TRANSAFE CORPORATION                     QUIXOTE TRANSPORTATION SAFETY (EUROPE),
                                         INC.

By:  /s/ Daniel P. Gorey                 By:  /s/ Daniel P. Gorey
   -----------------------------            --------------------------------
Name: Daniel P. Gorey                    Name: Daniel P. Gorey
Title(s): Vice President and Treasurer   Title(s): Vice President and Treasurer


NATIONAL SIGNAL, INC.

By:  /s/ Daniel P. Gorey
   -----------------------------
Name: Daniel P. Gorey
Title(s): Vice President and Treasurer