<Page>

EXHIBIT 10(a)

EXECUTION COPY

FIFTH AMENDMENT TO
AMENDED AND RESTATED LOAN AGREEMENT

THIS FIFTH AMENDMENT TO AMENDED AND RESTATED LOAN AGREEMENT (this
"FIFTH AMENDMENT"), dated as of December 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"), SURFACE SYSTEMS, INC., a Missouri corporation ("SSI"), 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, QTS
Australia, QTS Europe, National Signal, EAS Europe, TranSafe and SSI are
individually and collectively referred to herein as "BORROWER." This Fifth
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, that certain Third Amendment
and Waiver to Amended and Restated Loan Agreement dated as of May 17, 2000 and
that certain Fourth Amendment and Waiver to Amended and Restated Loan Agreement
dated as of January 31, 2001 (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, on August 31, 2001, Transportation acquired all of the
outstanding capital stock of SSI and SSI became and remains a wholly-owned
Subsidiary of Transportation;

WHEREAS, each Borrower desires to make SSI a Borrower under the Loan
Agreement;

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

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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, 2003" and
"October 31, 2007" in the definition of "Commitment
Termination Date" and replacing them with the dates "October
31, 2004" and "October 31, 2008" respectively; and

(b) deleting the reference to the date "November 1, 2003" in the
definition of "Conversion Date" and replacing it with the
date "November 1, 2004".

1.3 SECTION 6.3. SECTION 6.3(d) of the Loan Agreement is hereby deleted
in its entirety and replaced with the following:

"(d) at the end of each of the following periods, a Net
Consolidated Funded Debt to EBITDA Ratio (which shall be certified
by Quixote at the end of such period):

<Table>
<Caption>
---------------------------------------- ---------------------------------------
Maximum Funded
Period Debt to EBITDA
---------------------------------------- ---------------------------------------

---------------------------------------- ---------------------------------------
June 30, 1997 to December 31, 1997 less than or equal to 4.0 to 1.0
---------------------------------------- ---------------------------------------
January 1, 1998 to December 31, 1998 less than or equal to 3.75 to 1.0
---------------------------------------- ---------------------------------------
January 1, 1999 to December 31, 2001 less than or equal to 3.5 to 1.0
---------------------------------------- ---------------------------------------
January 1, 2002 and thereafter less than or equal to 3.0 to 1.0"
---------------------------------------- ---------------------------------------
</Table>

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 SSI
will henceforth be a "Borrower" under the Loan Agreement and, together with
Quixote, EAS, Transportation, Spin-Cast, E-Tech, Safe-Hit, HIS, Nu-Metrics, QTS
Australia, QTS Europe, National Signal, 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.

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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. 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
Fifth Amendment and the performance by the Borrower of its obligations under
this Fifth 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 SSI 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.

3. CONDITIONS OF EFFECTIVENESS.

The effectiveness of this Fifth Amendment is subject to the conditions
precedent that the Agent shall have received all of the following, in form and
substance satisfactory to the 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) FIFTH AMENDMENT. This Fifth 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 Fifth Amendment and the other documents provided
for in this Fifth 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 Fifth Amendment,
the Loan Agreement as amended hereby, the Amended and
Restated Revolving Credit Notes and other documents provided
for in this Fifth Amendment, (iii) for each of the
certificates of each Borrower other than SSI, there has been
no change in the Certificate of Incorporation or

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Bylaws for such Borrower since January 31, 2001 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) for
the certificate of SSI, true and correct copies of (A) the
Certificate of Incorporation of such corporation and all
amendments thereto, as certified by the secretary of state of
its jurisdiction of incorporation and (B) 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 January 31, 2001 pursuant to SECTION 2.1(b)
of the Loan Agreement;

(e) GOOD STANDING CERTIFICATE. A Good Standing Certificate for
SSI 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.

4. MISCELLANEOUS.

4.1 COUNTERPARTS. This Fifth 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.

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

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4.3 SUCCESSORS AND ASSIGNS. This Fifth 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.

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

4.5 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
Fifth 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).

4.6 CONSTRUCTION. THIS FIFTH 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, 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.

4.7 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 ACTON,
SUIT OR PROCEEDING BROUGHT TO ENFORCE OR DEFEND ANY RIGHTS OR REMEDIES UNDER
THIS FIFTH AMENDMENT, ANY OF THE OTHER LOAN DOCUMENTS OR ANY OF THE OTHER
AGREEMENTS.

4.8 AMENDMENT TO LOAN AGREEMENT. This Fifth 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]

5
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IN WITNESS WHEREOF, the parties hereto have caused this Fifth 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/ Greta Satek
---------------------------
Name: Greta Satek
Title: Vice President

LASALLE BANK NATIONAL ASSOCIATION,
as Lender

By: /s/ Stephanie Kline
---------------------------
Name: Stephanie Kline
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

<Page>

<Table>

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.

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

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

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

TRANSAFE CORPORATION QUIXOTE TRANSPORTATION SAFETY (EUROPE), INC.

NATIONAL SIGNAL, INC. SURFACE SYSTEMS, INC.

<Page>

EXHIBIT 10(a)

AMENDED AND RESTATED
REVOLVING CREDIT NOTE

$13,334,000 Chicago, Illinois
December 31, 2001

FOR VALUE RECEIVED, the undersigned, QUIXOTE CORPORATION,
ENERGY ABSORPTION SYSTEMS, INC. (f/k/a Quixote Laser Corporation and successor
by merger to Energy Absorption Systems, Inc. and Roadway Safety Service, Inc.),
TRANSAFE CORPORATION, SPIN-CAST PLASTICS, INC., E-TECH TESTING SERVICES, INC.,
SAFE-HIT CORPORATION, HIGHWAY INFORMATION SYSTEMS, INC., NU-METRICS, INC.,
QUIXOTE TRANSPORTATION SAFETY (ASIA PACIFIC) PTY LIMITED (f/k/a Energy
Absorption Systems Pty Limited), ENERGY ABSORPTION SYSTEMS (EUROPE), INC.,
QUIXOTE TRANSPORTATION SAFETY, INC. (f/k/a TranSafe Corporation), QUIXOTE
TRANSPORTATION SAFETY (EUROPE), INC., NATIONAL SIGNAL, INC. AND SURFACE SYSTEMS,
INC. (each individually a "Borrower" and collectively, the "Borrowers") hereby
JOINTLY AND SEVERALLY PROMISE TO PAY to the order of THE NORTHERN TRUST COMPANY
("Lender"), or its registered assigns, at 50 South LaSalle Street, Chicago,
Illinois 60675, or at such other place as the holder of this Note may designate
from time to time in writing, in lawful money of the United States of America
and in immediately available funds, the principal amount of THIRTEEN MILLION
THREE HUNDRED AND THIRTY-FOUR THOUSAND DOLLARS ($13,334,000), or such lesser
principal amount as may be outstanding pursuant to the Loan Agreement (as
hereinafter defined) with respect to the Revolving Credit Loan, together with
interest on the unpaid principal amount of this note outstanding from time to
time.

This Note is the Revolving Credit Note referred to in, and
evidences certain indebtedness incurred under, the Amended and Restated Loan
Agreement dated as of June 30, 1997 (herein as it may be amended, modified or
supplemented from time to time, the "Loan Agreement"), among each Borrower,
"Lenders" (as defined therein) and The Northern Trust Company, as agent for such
Lenders, and is entitled to the benefit and security of the "Loan Documents" (as
defined in the Loan Agreement) provided for therein, to which reference is
hereby made for a statement of all of the terms and conditions under which the
loan evidenced hereby is made. All capitalized terms herein, unless otherwise
defined, shall have the meanings ascribed to them in the Loan Agreement.

The principal amount of the indebtedness evidenced hereby
shall be payable in the amounts and on the dates specified in the Loan
Agreement. Interest thereon, less any taxes payable by withholding, shall be
paid until such principal amount is paid in full at such interest rates and at
such times as are specified in the Loan Agreement.

If any payment on this Note becomes due and payable on a
day other than a Business Day, the maturity thereof shall be extended to the
next succeeding Business Day and,

<Page>

with respect to payments of principal, interest thereon shall be payable at
the then applicable rate during such extension.

Upon and after the occurrence of an Event of Default, this
Note shall or may, as provided in the Loan Agreement, and without demand, notice
or legal process of any kind, become or be declared immediately due and payable.

The right to receive principal of, and stated interest on,
this Note may only be transferred through Borrower's book entry system.

Demand, presentment, protest and notice of nonpayment and
protest are hereby waived by Borrower.

This Note shall be interpreted, governed by, and construed in
accordance with the internal laws of the State of Illinois.

THIS NOTE, ISSUED AND DELIVERED ON THE DATE HEREOF TO THE
AGENT, ON BEHALF OF THE LENDERS, IS ISSUED IN REPLACEMENT AND SUBSTITUTION FOR,
AND NOT IN PAYMENT OF THAT CERTAIN AMENDED AND RESTATED REVOLVING CREDIT NOTE IN
THE ORIGINAL PRINCIPAL AMOUNT OF $13,334,000 DATED JANUARY 31, 2001 (WHICH IN
TURN WAS ISSUED IN SUBSTITUTION AND REPLACEMENT OF THAT CERTAIN AMENDED AND
RESTATED REVOLVING CREDIT NOTE IN THE ORIGINAL PRINCIPAL AMOUNT OF $13,334,000
DATED MAY 17, 2000 WHICH IN TURN WAS ISSUED IN SUBSTITUTION AND REPLACEMENT OF
THAT CERTAIN AMENDED AND RESTATED REVOLVING CREDIT NOTE IN THE ORIGINAL
PRINCIPAL AMOUNT OF $13,334,000 DATED MARCH 15, 1999 WHICH IN TURN WAS ISSUED IN
SUBSTITUTION AND REPLACEMENT OF THAT CERTAIN AMENDED AND RESTATED REVOLVING
CREDIT NOTE IN THE ORIGINAL PRINCIPAL AMOUNT OF $13,334,000 DATED JUNE 30, 1997
WHICH IN TURN WAS ISSUED IN SUBSTITUTION AND REPLACEMENT OF THAT CERTAIN
REVOLVING CREDIT NOTE IN THE ORIGINAL PRINCIPAL AMOUNT OF $21,666,668 DATED
MARCH 31, 1996 WHICH IN TURN WAS ISSUED IN SUBSTITUTION AND REPLACEMENT OF THAT
CERTAIN REVOLVING CREDIT NOTE IN THE PRINCIPAL AMOUNT OF $23,333,334 DATED
NOVEMBER 10, 1995) AND NOTHING CONTAINED HEREIN SHALL BE CONSTRUED TO DEEM PAID
OR FORGIVEN THE UNPAID PRINCIPAL AMOUNT OF, OR UNPAID ACCRUED INTEREST ON, SAID
NOTE AT THE TIME OF ITS REPLACEMENT BY THIS NOTE.

* * *

<Page>
IN WITNESS WHEREOF, the parties hereto have caused this Amended
and Restated Revolving Credit Note to be executed by their duly authorized
officers as of the day and year first written above.

<Table>

QUIXOTE CORPORATION ENERGY ABSORPTION SYSTEMS, INC.

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

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

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

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

TRANSAFE CORPORATION QUIXOTE TRANSPORTATION SAFETY (EUROPE), INC.

NATIONAL SIGNAL, INC. SURFACE SYSTEMS, INC.

<Page>

AMENDED AND RESTATED
REVOLVING CREDIT NOTE

$13,333,000 Chicago, Illinois
December 31, 2001

FOR VALUE RECEIVED, the undersigned, QUIXOTE CORPORATION,
ENERGY ABSORPTION SYSTEMS, INC. (f/k/a Quixote Laser Corporation and
successor by merger to Energy Absorption Systems, Inc. and Roadway Safety
Service, Inc.), TRANSAFE CORPORATION, SPIN-CAST PLASTICS, INC., E-TECH
TESTING SERVICES, INC., SAFE-HIT CORPORATION, HIGHWAY INFORMATION SYSTEMS,
INC., NU-METRICS, INC., QUIXOTE TRANSPORTATION SAFETY (ASIA PACIFIC) PTY
LIMITED (f/k/a Energy Absorption Systems Pty Limited), ENERGY ABSORPTION
SYSTEMS (EUROPE), INC., QUIXOTE TRANSPORTATION SAFETY, INC. (f/k/a TranSafe
Corporation), QUIXOTE TRANSPORTATION SAFETY (EUROPE), INC., NATIONAL SIGNAL,
INC. AND SURFACE SYSTEMS, INC. (each individually a "Borrower" and
collectively, the "Borrowers") hereby JOINTLY AND SEVERALLY PROMISE TO PAY to
the order of AMERICAN NATIONAL BANK AND TRUST COMPANY OF CHICAGO ("Lender"),
or its registered assigns, at 30 South Wacker Drive, Chicago, Illinois
60606, or at such other place as the holder of this Note may designate from
time to time in writing, in lawful money of the United States of America and
in immediately available funds, the principal amount of THIRTEEN MILLION
THREE HUNDRED AND THIRTY-THREE THOUSAND DOLLARS ($13,333,000), or such lesser
principal amount as may be outstanding pursuant to the Loan Agreement (as
hereinafter defined) with respect to the Revolving Credit Loan, together with
interest on the unpaid principal amount of this note outstanding from time to
time.

If any payment on this Note becomes due and payable on a
day other than a Business Day, the maturity thereof shall be extended to the
next succeeding Business Day and, with respect to payments of principal,
interest thereon shall be payable at the then applicable rate during such
extension.

<Page>

The right to receive principal of, and stated interest on,
this Note may only be transferred through Borrower's book entry system.

Demand, presentment, protest and notice of nonpayment and
protest are hereby waived by Borrower.

This Note shall be interpreted, governed by, and construed in
accordance with the internal laws of the State of Illinois.

THIS NOTE, ISSUED AND DELIVERED ON THE DATE HEREOF TO THE
AGENT, ON BEHALF OF THE LENDERS, IS ISSUED IN REPLACEMENT AND SUBSTITUTION FOR,
AND NOT IN PAYMENT OF THAT CERTAIN AMENDED AND RESTATED REVOLVING CREDIT NOTE IN
THE ORIGINAL PRINCIPAL AMOUNT OF $13,333,000 DATED JANUARY 31, 2001 (WHICH IN
TURN WAS ISSUED IN SUBSTITUTION AND REPLACEMENT OF THAT CERTAIN AMENDED AND
RESTATED REVOLVING CREDIT NOTE IN THE ORIGINAL PRINCIPAL AMOUNT OF $13,333,000
DATED MAY 17, 2000 WHICH IN TURN WAS ISSUED IN SUBSTITUTION AND REPLACEMENT OF
THAT CERTAIN AMENDED AND RESTATED REVOLVING CREDIT NOTE IN THE ORIGINAL
PRINCIPAL AMOUNT OF $13,333,000 DATED MARCH 15, 1999 WHICH IN TURN WAS ISSUED IN
SUBSTITUTION AND REPLACEMENT OF THAT CERTAIN AMENDED AND RESTATED REVOLVING
CREDIT NOTE IN THE ORIGINAL PRINCIPAL AMOUNT OF $13,333,000 DATED JUNE 30, 1997
WHICH IN TURN WAS ISSUED IN SUBSTITUTION AND REPLACEMENT OF THAT CERTAIN
REVOLVING CREDIT NOTE IN THE ORIGINAL PRINCIPAL AMOUNT OF $21,666,666 DATED
MARCH 31, 1996 WHICH IN TURN WAS ISSUED IN SUBSTITUTION AND REPLACEMENT OF THAT
CERTAIN REVOLVING CREDIT NOTE IN THE PRINCIPAL AMOUNT OF $23,333,333 DATED
NOVEMBER 10, 1995) AND NOTHING CONTAINED HEREIN SHALL BE CONSTRUED TO DEEM PAID
OR FORGIVEN THE UNPAID PRINCIPAL AMOUNT OF, OR UNPAID ACCRUED INTEREST ON, SAID
NOTE AT THE TIME OF ITS REPLACEMENT BY THIS NOTE.

* * *

<Page>

IN WITNESS WHEREOF, the parties hereto have caused this Amended
and Restated Revolving Credit Note to be executed by their duly authorized
officers as of the day and year first written above.

<Table>

QUIXOTE CORPORATION ENERGY ABSORPTION SYSTEMS, INC.

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

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

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

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

TRANSAFE CORPORATION QUIXOTE TRANSPORTATION SAFETY (EUROPE), INC.

NATIONAL SIGNAL, INC. SURFACE SYSTEMS, INC.

<Page>

AMENDED AND RESTATED
REVOLVING CREDIT NOTE

$13,333,000 Chicago, Illinois
December 31, 2001

FOR VALUE RECEIVED, the undersigned, QUIXOTE CORPORATION,
ENERGY ABSORPTION SYSTEMS, INC. (f/k/a Quixote Laser Corporation and
successor by merger to Energy Absorption Systems, Inc. and Roadway Safety
Service, Inc.), TRANSAFE CORPORATION, SPIN-CAST PLASTICS, INC., E-TECH
TESTING SERVICES, INC., SAFE-HIT CORPORATION, HIGHWAY INFORMATION SYSTEMS,
INC., NU-METRICS, INC., QUIXOTE TRANSPORTATION SAFETY (ASIA PACIFIC) PTY
LIMITED (f/k/a Energy Absorption Systems Pty Limited), ENERGY ABSORPTION
SYSTEMS (EUROPE), INC., QUIXOTE TRANSPORTATION SAFETY, INC. (f/k/a TranSafe
Corporation), QUIXOTE TRANSPORTATION SAFETY (EUROPE), INC., NATIONAL SIGNAL,
INC. AND SURFACE SYSTEMS, INC. (each individually a "Borrower" and
collectively, the "Borrowers") hereby JOINTLY AND SEVERALLY PROMISE TO PAY to
the order of LASALLE BANK NATIONAL ASSOCIATION ("Lender"), or its registered
assigns, at 135 South LaSalle Street, Chicago, Illinois 60603, or at such
other place as the holder of this Note may designate from time to time in
writing, in lawful money of the United States of America and in immediately
available funds, the principal amount of THIRTEEN MILLION THREE HUNDRED AND
THIRTY-THREE THOUSAND DOLLARS ($13,333,000), or such lesser principal amount
as may be outstanding pursuant to the Loan Agreement (as hereinafter defined)
with respect to the Revolving Credit Loan, together with interest on the
unpaid principal amount of this note outstanding from time to time.

If any payment on this Note becomes due and payable on a day
other than a Business Day, the maturity thereof shall be extended to the next
succeeding Business Day and, with respect to payments of principal, interest
thereon shall be payable at the then applicable rate during such extension.

<Page>

The right to receive principal of, and stated interest on,
this Note may only be transferred through Borrower's book entry system.

Demand, presentment, protest and notice of nonpayment and
protest are hereby waived by Borrower.

This Note shall be interpreted, governed by, and construed in
accordance with the internal laws of the State of Illinois.

THIS NOTE, ISSUED AND DELIVERED ON THE DATE HEREOF TO THE
AGENT, ON BEHALF OF THE LENDERS, IS ISSUED IN REPLACEMENT AND SUBSTITUTION FOR,
AND NOT IN PAYMENT OF THAT CERTAIN AMENDED AND RESTATED REVOLVING CREDIT NOTE IN
THE ORIGINAL PRINCIPAL AMOUNT OF $13,333,000 DATED JANUARY 31, 2001 (WHICH IN
TURN WAS ISSUED IN SUBSTITUTION AND REPLACEMENT OF THAT CERTAIN AMENDED AND
RESTATED REVOLVING CREDIT NOTE IN THE ORIGINAL PRINCIPAL AMOUNT OF $13,333,000
DATED MAY 17, 2000 WHICH IN TURN WAS ISSUED IN SUBSTITUTION AND REPLACEMENT OF
THAT CERTAIN AMENDED AND RESTATED REVOLVING CREDIT NOTE IN THE ORIGINAL
PRINCIPAL AMOUNT OF $13,333,000 DATED MARCH 15, 1999 WHICH IN TURN WAS ISSUED IN
SUBSTITUTION AND REPLACEMENT OF THAT CERTAIN AMENDED AND RESTATED REVOLVING
CREDIT NOTE IN THE ORIGINAL PRINCIPAL AMOUNT OF $13,333,000 DATED JUNE 30, 1997
WHICH IN TURN WAS ISSUED IN SUBSTITUTION AND REPLACEMENT OF THAT CERTAIN
REVOLVING CREDIT NOTE IN THE ORIGINAL PRINCIPAL AMOUNT OF $21,666,666 DATED
MARCH 31, 1996 WHICH IN TURN WAS ISSUED IN SUBSTITUTION AND REPLACEMENT OF THAT
CERTAIN REVOLVING CREDIT NOTE IN THE PRINCIPAL AMOUNT OF $23,333,333 DATED
NOVEMBER 10, 1995) AND NOTHING CONTAINED HEREIN SHALL BE CONSTRUED TO DEEM PAID
OR FORGIVEN THE UNPAID PRINCIPAL AMOUNT OF, OR UNPAID ACCRUED INTEREST ON, SAID
NOTE AT THE TIME OF ITS REPLACEMENT BY THIS NOTE.

* * *
<Page>

IN WITNESS WHEREOF, the parties hereto have caused this Amended
and Restated Revolving Credit Note to be executed by their duly authorized
officers as of the day and year first written above.

<Table>

QUIXOTE CORPORATION ENERGY ABSORPTION SYSTEMS, INC.

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

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

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

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

TRANSAFE CORPORATION QUIXOTE TRANSPORTATION SAFETY (EUROPE), INC.

NATIONAL SIGNAL, INC. SURFACE SYSTEMS, INC.