<PAGE>
 
                                                                   Exhibit 10.23
 
DRAFT DATED 12/1/98
 
 
 
                               CREDIT AGREEMENT



                                 By and Among



                             MASTECH CORPORATION,
                                  as Borrower

                                      and

                   THE FINANCIAL INSTITUTIONS PARTY HERETO,
                                 as Lenders

                                      and

                        PNC BANK, NATIONAL ASSOCIATION,
                          as Agent and as L/C Issuer



                          Dated as of December 3, 1998



<PAGE>
 
                               TABLE OF CONTENTS
                              -------------------
<TABLE>
<CAPTION>

<C>           <S>                                                                                       <C> 
SCHEDULES     ........................................................................................  iv

EXHIBITS      ........................................................................................   v
 
ARTICLE I     CERTAIN DEFINITIONS; CONSTRUCTION.......................................................   1
 
       1.01.  Certain Definitions.....................................................................   1
       1.02.  Construction............................................................................  18
       1.03.  Accounting Principles...................................................................  20
 
ARTICLE II    REVOLVING CREDIT FACILITY...............................................................  20
 
       2.01.  Revolving Credit Commitments............................................................  20
       2.02.  Nature of Lenders' Obligations with Respect to Loans....................................  20
       2.03.  Commitment Fees.........................................................................  21
       2.04.  Reduction of Revolving Credit Commitment................................................  21
       2.05.  Loan Requests...........................................................................  22
       2.06.  Making Loans............................................................................  22
       2.07.  Notes...................................................................................  22
       2.08.  Interest Payments, Interest Rates and Certain Related Payments Pertaining to the Loans..  23
       2.09.  Prepayments: Allocation of Repayments...................................................  26
       2.10.  Yield Protection........................................................................  27
       2.11.  Special Provisions Relating to the Euro-Rate Option.....................................  28
       2.12.  Capital Adequacy........................................................................  30
       2.13.  Utilization of Commitments in Optional Currencies.......................................  30
       2.14.  Interbank Market Presumption............................................................  34
       2.15.  Loan Account............................................................................  34
       2.16.  All Advances to Constitute One Loan.....................................................  34
       2.17.  Use of Proceeds.........................................................................  34
       2.18.  Letter of Credit Subfacility............................................................  34
       2.19.  Taxes...................................................................................  42
       2.20.  Payments................................................................................  43
       2.21.  Judgment Currency.......................................................................  44
 
ARTICLE III   LOAN DISBURSEMENT ACCOUNT, GUARANTEES, ETC..............................................  44
 
       3.01.  Loan Disbursement Account...............................................................  44
       3.02.  Designation of Subsidiary Guarantors....................................................  44
       3.03.  Foreign Subsidiaries....................................................................  45
       3.04.  Further Cooperation.....................................................................  45
 
ARTICLE IV    REPRESENTATIONS AND WARRANTIES..........................................................  45
 
       4.01.  Organization and Qualification..........................................................  45
       4.02.  Capitalization and Ownership............................................................  45
       4.03.  Subsidiaries............................................................................  46
       4.04.  Power and Authority.....................................................................  46
       4.05.  Validity and Binding Effect.............................................................  46
       4.06.  No Conflict.............................................................................  46
       4.07.  Litigation..............................................................................  47
       4.08.  Financial Statements....................................................................  47

</TABLE>

                                       i



<PAGE>

<TABLE> 

<C>           <S>                                                                                       <C>
       4.09.  Margin Stock; Section 20 Subsidiaries...................................................  47
       4.10.  Full Disclosure.........................................................................  47
       4.11.  Tax Returns and Payments................................................................  48
       4.12.  Consents and Approvals..................................................................  48
       4.13.  No Event of Default; Compliance with Instruments........................................  48
       4.14.  Compliance with Laws....................................................................  48
       4.15.  Investment Company; Public Utility Holding Company......................................  48
       4.16.  Plans and Benefit Arrangements..........................................................  49
       4.17.  Title to Properties.....................................................................  50
       4.18.  Insurance...............................................................................  50
       4.19.  Employment Matters......................................................................  50
       4.20.  Environmental Matters...................................................................  50
       4.21.  Senior Debt Status......................................................................  52
       4.22.  Solvency................................................................................  52
       4.23.  Material Contracts; Burdensome Restrictions.............................................  52
       4.24.  Patents, Trademarks, Copyrights, Licenses, etc..........................................  52
       4.25.  Year 2000 Problem.......................................................................  52
       4.26.  Brokers.................................................................................  53
       4.27.  No Material Adverse Change..............................................................  53
 
ARTICLE V     CONDITIONS OF LENDING OR ISSUANCE OF LETTER OF CREDIT...................................  53
 
       5.01.  Conditions to Initial Borrowings........................................................  53
       5.02.  Each Additional Loan or Issuance of a Letter of Credit..................................  55
       5.03.  Location of Closing.....................................................................  56
 
ARTICLE VI    AFFIRMATIVE COVENANTS...................................................................  56
 
       6.01.  Preservation of Existence, Etc..........................................................  56
       6.02.  Accounting System; Reporting Requirements...............................................  57
       6.03.  Notices Regarding Plans and Benefit Arrangements........................................  58
       6.04.  Payment of Liabilities, Including Taxes, etc............................................  60
       6.05.  Maintenance of Insurance................................................................  60
       6.06.  Maintenance of Properties and Leases....................................................  60
       6.07.  Maintenance of Permits and Franchises...................................................  60
       6.08.  Visitation Rights.......................................................................  60
       6.09.  Keeping of Records and Books of Account.................................................  61
       6.10.  Plans and Benefit Arrangements..........................................................  61
       6.11.  Compliance with Laws....................................................................  61
       6.12.  Use of Proceeds.........................................................................  61
       6.13.  Environmental Laws......................................................................  61
       6.14.  Senior Debt Status......................................................................  62
 
ARTICLE VII   NEGATIVE COVENANTS......................................................................  62
 
       7.01.  Indebtedness............................................................................  62
       7.02.  Liens...................................................................................  63
       7.03.  Loans, Acquisitions and Investments.....................................................  63
       7.04.  Liquidations, Mergers and Consolidations................................................  64
       7.05.  Dispositions of Assets or Subsidiaries..................................................  65
       7.06.  Affiliate Transactions..................................................................  65
       7.07.  Subsidiaries, Partnerships and Joint Ventures...........................................  66
       7.08.  Continuation of or Change in Business...................................................  66
</TABLE>

                                      ii
<PAGE>

<TABLE> 
 
<C>           <S>                                                                                       <C>
       7.09.  Plans and Benefit Arrangements..........................................................  66
       7.10.  Fiscal Year.............................................................................  67
       7.11.  Changes in Organizational Documents.....................................................  67
       7.12.  Financial Covenants.....................................................................  67
 
ARTICLE VIII  DEFAULT.................................................................................  67
 
       8.01.  Events of Default.......................................................................  67
       8.02.  Consequences of Event of Default........................................................  70
 
ARTICLE IX    THE AGENT...............................................................................  72
 
       9.01.  Appointment and Grant of Authority......................................................  72
       9.02.  Delegation of Duties....................................................................  72
       9.03.  Reliance by Agent on Lenders for Funding................................................  73
       9.04.  Non-Reliance on Agent...................................................................  73
       9.05.  Responsibility of Agents and Other Matters..............................................  73
       9.06.  Actions in Discretion of Agent; Instructions from the Lenders...........................  74
       9.07.  Indemnification.........................................................................  74
       9.08.  Agent's Rights as Lender................................................................  75
       9.09.  Notice of Default.......................................................................  75
       9.10.  Payment to Lenders......................................................................  75
       9.11.  Holders of Notes........................................................................  76
       9.12.  Equalization of Lenders.................................................................  76
       9.13.  Successor Agent.........................................................................  76
       9.14.  Calculations............................................................................  77
       9.15.  Beneficiaries...........................................................................  77
 
ARTICLE X     GENERAL PROVISIONS......................................................................  77
 
      10.01.  Amendments and Waivers..................................................................  77
      10.02.  Taxes...................................................................................  78
      10.03.  Costs and Expenses, etc.................................................................  78
      10.04.  Notices.................................................................................  78
      10.05.  Participation and Assignment............................................................  80
      10.06.  Successors and Assigns..................................................................  82
      10.07.  No Implied Waivers; Cumulative Remedies; Writing Required...............................  82
      10.08.  Severability............................................................................  83
      10.09.  Indemnity...............................................................................  83
      10.10.  Confidentiality.........................................................................  83
      10.11.  Survival................................................................................  84
      10.12.  GOVERNING LAW...........................................................................  84
      10.13.  FORUM...................................................................................  84
      10.14.  Non-Business Days.......................................................................  85
      10.15.  Integration.............................................................................  85
      10.16.  Counterparts............................................................................  85
      10.17.  Funding by Branch, Subsidiary or Affiliate..............................................  85
      10.18.  WAIVER OF JURY TRIAL....................................................................  86
</TABLE>

                                      iii
<PAGE>
 
                                   SCHEDULES
                                   ---------


     Schedule 1.01(a)  Lenders; Commitments
     Schedule 4.01     Jurisdictions of Incorporation and Qualification of
                       Borrower and Subsidiaries
     Schedule 4.02     Capital Stock Options
     Schedule 4.03     Interests in Subsidiaries and Other Entities
     Schedule 4.07     Litigation
     Schedule 4.11     Agreements Concerning Tax Returns
     Schedule 4.12     Consents and Approvals
     Schedule 4.16     Plans and Benefit Arrangements
     Schedule 4.20     Environmental Matters
     Schedule 7.01     Permitted Indebtedness
     Schedule 7.03     Other Investments
     Schedule 7.06     Affiliate Transactions

                                       iv
<PAGE>
 
                                 EXHIBITS
                                 --------


Exhibit "A"    Form of Note
Exhibit "B"    Form of Loan Request
Exhibit "C"    Form of Subsidiary Guaranty
Exhibit "D"    Form of Pledge Agreement
Exhibit "E"    Form of Compliance Certificate
Exhibit "F"    Form of Opinion of Counsel
Exhibit "G"    Form of Assignment and Assumption Agreement

                                       v
<PAGE>
 
                                 CREDIT AGREEMENT

          THIS CREDIT AGREEMENT, dated as of December 3, 1998, is made by and
among MASTECH CORPORATION, a Pennsylvania corporation (as more fully defined
below, the "Borrower"), the Lenders (as hereinafter defined), and PNC BANK,
NATIONAL ASSOCIATION, in its capacity as L/C Issuer (as hereinafter defined) and
as agent for the L/C Issuer and the Lenders under this Agreement (in such
capacity, as more fully defined below, the "Agent").

                                  WITNESSETH:

          WHEREAS, the Borrower has requested the Lenders to make available to
the Borrower Loans in an aggregate principal amount not exceeding Seventy-Five
Million Dollars ($75,000,000) at any one time outstanding; and the Borrower has
requested the Lenders to provide for the issuance for the account of the
Borrower Letters of Credit with an aggregate Stated Amount not exceeding Ten
Million Dollars ($10,000,000) at any one time outstanding; provided that at no
time will Total Utilization exceed Seventy-Five Million Dollars ($75,000,000);
and

          WHEREAS, the Lenders are willing to make the Loans available to the
Borrower upon the terms and conditions hereinafter set forth; and the L/C Issuer
is willing to issue Letters of Credit for the account of the Borrower and its
Subsidiaries upon the terms and conditions hereinafter set forth; and the
Lenders are willing to purchase risk participations with respect to each Letter
of Credit issued by the L/C Issuer hereunder upon the terms and conditions
hereinafter set forth.

          NOW, THEREFORE, in consideration of the premises (each of which is
incorporated herein by reference) and the mutual covenants and agreements
hereinafter set forth, and other valuable consideration, and intending to be
legally bound hereby, the parties hereto hereby covenant and agree as follows:

                                   ARTICLE I
                       CERTAIN DEFINITIONS; CONSTRUCTION
                       ---------------------------------

          1.01.  Certain Definitions. In addition to words and terms defined
                 -------------------                                          
elsewhere in this Agreement, the following words and terms shall have the
following meanings, respectively, unless the context hereof clearly requires
otherwise:

          Affiliate as to any Person shall mean any other Person (i) which
          ---------                                                       
directly or indirectly Controls, is Controlled by, or is under common Control
with such Person, (ii) which beneficially owns or holds 5 % or more of any class
of the voting or other equity interests of such Person, or (iii) 5 % or more of
any class of voting interests or other equity interests of which is beneficially
owned or held, directly or indirectly, by such Person.

          Agent shall mean PNC Bank, National Association, a national banking
          -----                                                              
association organized under the laws of the United States of America, in its
capacity as agent for the L/C Issuer and the Lenders pursuant to this Agreement,
and its successors and assigns in such capacity.
<PAGE>
 
          Agent's Fee shall mean the annual fee payable to the Agent for acting
          -----------                                                          
as Agent hereunder, all as more fully set forth in the Agent's Letter.

          Agent's Letter shall mean the letter from the Agent to the Borrower
          --------------                                                     
dated December 3, 1998, as the same may be amended from time to time or
otherwise modified or supplemented.

          Agreement shall mean this Credit Agreement, as the same may be
          ---------                                                     
supplemented or amended from time to time, including all schedules and exhibits
hereto.

          Applicable Commitment Fee shall have the meaning ascribed to it in
          ------------------------- 
Section 2.03 of this Agreement.

          Applicable Euro-Rate Margin shall have the meaning ascribed to it in
          ---------------------------
Section 2.08(b)(ii) of this Agreement.

          Applicable Standby Letter of Credit Fee shall have the meaning
          ---------------------------------------
ascribed to it in Section 2.18(b) of this Agreement.

          Application for Commercial Letter of Credit shall mean the then
          -------------------------------------------                    
current application for a commercial letter of credit used by the L/C Issuer.

          Application for Letter of Credit shall mean the then current
          --------------------------------                            
application for Standby Letter of Credit or Commercial Letter of Credit.

          Application for Standby Letter of Credit shall mean the then current
          ----------------------------------------                            
application for a standby letter of credit used by the L/C Issuer.

          Assignment and Assumption Agreement shall mean an Assignment and
          -----------------------------------                             
Assumption Agreement by and among a Purchasing Lender, a Transferor Lender and
the Agent, as the Agent and on behalf of the remaining Lenders, substantially in
the form of Exhibit "G" hereto.
            -----------        

          Arrangement Fee shall mean the arrangement fee set forth in the
          ---------------                                                
Agent's Letter.

          Assignment Fee shall mean the fee described in Section 10.05(b).
          --------------

          Authorized Officer shall mean those persons designated initially in
          ------------------                                                 
the several incumbency certificates delivered pursuant to Section 5.01 hereof by
the Borrower or a Subsidiary Guarantor, as the case may be. The Borrower, or a
Subsidiary Guarantor, as the case may be, may amend such list of persons from
time to time by giving written notice of such amendment to the Agent.

          Availability shall mean, as of any time of determination, the positive
          ------------                                                          
difference between the Revolving Credit Commitment and Total Utilization.
<PAGE>
 
          Base Rate shall mean the greater of (i) the Prime Rate, or (ii) the
          ---------                                                          
Federal Funds Effective Rate plus fifty basis points (1/2 of 1 %) per annum.

          Base Rate Option shall mean the interest rate option described in
          ---------------- 
Section 2.08(b)(i) hereof.

          Base Rate Portion shall mean the portion of the Loans which bears,
          -----------------
or is to bear, interest under the Base Rate Option.

          Benefit Arrangement shall mean at any time an "employee benefit plan",
          -------------------                                                   
within the meaning of Section 3(3) of ERISA, which is neither a Plan nor a
Multiemployer Plan and which is maintained, sponsored or otherwise contributed
to, by any member of the ERISA Group.

          Borrower shall mean Mastech Corporation, a corporation organized and
          --------                                                            
existing under the laws of the Commonwealth of Pennsylvania, and its successors
and permitted assigns.

          Borrowing Date shall mean, with respect to any Loan, the date for the
          --------------                                                       
making thereof, or the renewal or conversion thereof at or to the same or a
different Interest Rate Option, which shall be a Business Day.

          Business Day shall mean, (a) when used in any context other than in
          ------------                                                       
reference to or in connection with Euro-Rate, any day, other than a Saturday or
Sunday, on which the Lenders are open for business in Pittsburgh, Pennsylvania
and New York, New York, (b) when used in the context of a Euro-Rate, any day,
other than a Saturday or Sunday, on which (i) commercial banks are open for
business in Pittsburgh, Pennsylvania and New York, New York and (ii) dealings in
foreign currencies and exchange and eurodollar funding between banks may be
carried on at the location at which each of the Lenders transacts its eurodollar
funding, and (c) when used with respect to advances or payments of Loans or any
other matters relating to Loans denominated in an Optional Currency, such day
also shall be a day on which dealings in deposits in the relevant Optional
Currency are carried on in the applicable interbank market or on which all
applicable banks into which Loan proceeds may be deposited are open for business
and foreign exchange markets are open for business in the principal financial
center of the country of such currency.

          Capital Adequacy Event shall have the meaning ascribed to it in
          ----------------------
Section 2.12 hereof.

          Capital Compensation Amount shall have the meaning ascribed to it in
          ---------------------------
Section 2.12 hereof.

          Cash Collateral Account shall have the meaning ascribed to it in
          -----------------------
Section 8.02(e).


          Cash Equivalents shall mean (i) securities issued or directly and
          ----------------                                                 
fully guaranteed or insured by the United States Government or any agency or
instrumentality thereof, (ii) time deposits, certificates of deposit and
eurodollar time deposits, bankers' acceptances and overnight bank deposits, in
each case with any Lender or with any domestic commercial bank
<PAGE>
 
having capital and surplus in excess of $500,000,000 (iii) notes and bonds
issued by domestic corporations, (iv) tax-exempt money market securities, (v)
notes and bonds issued by state and municipal governments, and (vi) money market
mutual funds;
                                                                              
provided however, (x) at least one-third of the value of the Cash Equivalents
-------- -------                                                             
shall have a maximum weighted average to maturity of not more than six (6)
months and the remaining value of the Cash Equivalents shall have a maximum
weighted average to maturity of not more than eighteen (18) months and (y) the
Cash Equivalents which are of a type customarily rated by S&P and Moody's, must
have a rating of at least A-1 by S&P or P-1/VMG-1 by Moody's, if short term, or
double "A" or higher by S&P and Moody's, if long term.

          Closing shall mean the execution and delivery of this Agreement and
          -------                                                            
the other Loan Documents by the parties hereto and thereto on the Closing Date.

          Closing Date shall mean December 3, 1998.
          ------------

          Closing Fee shall mean a fee in the amount of $56,250 payable on the
          -----------                                                         
Closing Date in proportion to each Lender's Ratable Share.

          Commercial Letter of Credit shall mean a letter of credit directly
          ---------------------------                                       
related to the sale of goods or similar transaction in which it is intended by
the account party and beneficiary that payment will be made, in the ordinary
course, by a draw on the letter of credit in accordance with its terms.

          Commercial Letter of Credit Fee shall have the meaning ascribed to it
          -------------------------------                                      
in Section 2.18(b) hereof.

          Commitment Fee shall mean the fee described in Section 2.03.
          --------------

          Compliance Certificate shall mean a certificate executed by the chief
          ----------------------                                               
financial officer, the treasurer or the controller of the Borrower,
substantially in the form of Exhibit "E" hereto.
                             -----------        

          Computation Date shall have the meaning ascribed to it in Section
          ----------------
2.13(a).

          Consolidated Cash shall mean the Borrower's and its Subsidiaries
          ------------------
cash consolidated in accordance with GAAP.

          Consolidated Cash Equivalents shall mean the Borrower's and its
          -----------------------------                                  
Subsidiaries Cash Equivalents consolidated in accordance with GAAP.

          Consolidated EBIT shall mean, for any period, the consolidated net
          -----------------                                                 
income (or net loss) of the Borrower and its Subsidiaries for such period as
determined in accordance with GAAP, plus (a) the sum of (i) Consolidated
                                    ----                                
Interest Expense, (ii) total income tax expense, (iii) extraordinary or unusual
losses (including after tax losses on sales of assets outside of the ordinary
course of business and not otherwise included in GAAP extraordinary or unusual
losses), (iv) other non-cash charges other than depreciation and amortization,
and (v) the net loss of any Person that is accounted for by the equity method of
accounting, except to the extent of the amount of dividends or distributions
paid to the Borrower, less (b) the sum of (i)
                      ----
<PAGE>
 
extraordinary or unusual gains (including after tax gains on sales of assets
outside of the ordinary course of business and not otherwise included in GAAP
extraordinary or nonrecurring gains), (ii) other noncash credits, and (iii) the
net income of any Person that is accounted for by the equity method of
accounting, except to the extent of the amount of dividends or distributions
paid to the Borrower; provided, that for purposes of calculating Consolidated
                      --------
EBIT of the Borrower and its Subsidiaries for any period, (x) the Consolidated
EBIT for any Person disposed of by the Borrower or its Subsidiaries during such
period shall be excluded for such period and (y) the Consolidated EBIT of any
Person acquired by the Borrower or its Subsidiaries during such period shall be
included on a pro forma basis for such period (and assuming the consummation of
              ---------
each such acquisition and the incurrence or assumption of any Indebtedness in
connection therewith occurred on the first day of such period) if the
consolidated balance sheet of such acquired Person and its consolidated
Subsidiaries as at the end of the period preceding the acquisition of such
Person and related consolidated statements of income and stockholders' equity
and of cash flows for such period (i) have been previously provided to the Agent
and the Lenders and (ii) either (A) have been reported on without qualification
arising out of the scope of the audit by independent certified accountants of
nationally recognized standing or (B) have been found acceptable by the Agent,
and the Required Lenders.

          Consolidated EBITDA shall mean, for any period, the consolidated net
          -------------------                                                 
income (or net loss) of the Borrower and its Subsidiaries for such period as
determined in accordance with GAAP, plus (a) the sum of (i) depreciation
                                    ----                                
expense, (ii) amortization expense, (iii) Consolidated Interest Expense, (iv)
total income tax expense, (v) extraordinary or unusual losses (including after
tax losses on sales of assets outside of the ordinary course of business and not
otherwise included in GAAP extraordinary or unusual losses), (vi) other non-cash
charges, and (vii) the net loss of any Person that is accounted for by the
equity method of accounting, except to the extent of the amount of dividends or
distributions paid to the Borrower, less (b) the sum of (i) extraordinary or
                                    ----                                    
unusual gains (including after tax gains on sales of assets outside of the
ordinary course of business and not otherwise included in GAAP extraordinary or
nonrecurring gains), (ii) other noncash credits, and (iii) the net income of any
Person that is accounted for by the equity method of accounting, except to the
extent of the amount of dividends or distributions paid to the Borrower;
                                                                        
provided, that for purposes of calculating Consolidated EBITDA of the Borrower
--------                                                                      
and its Subsidiaries for any period, (x) the Consolidated EBITDA of any Person
disposed of by the Borrower or its Subsidiaries during such period shall be
excluded for such period and (y) the Consolidated EBITDA of any Person acquired
by the Borrower or its Subsidiaries during such period shall be included on a
                                                                             
pro forma basis for such period (and assuming the consummation of each such
---------                                                                  
acquisition and the incurrence or assumption of any Indebtedness in connection
therewith occurred on the first day of such period) if the consolidated balance
sheet of such acquired Person and its consolidated Subsidiaries as at the end of
the period preceding the acquisition of such Person and related consolidated
statements of income and stockholders' equity and of cash flows for such period
(i) have been previously provided to the Agent and the Lenders and (ii) either
(A) have been reported on without qualification arising out of the scope of the
audit by independent certified accountants of nationally recognized standing or
(B) have been found acceptable by the Agent, and the Required Lenders.

          Consolidated Interest Expense shall mean any Person's interest
          -----------------------------                                 
expense, as determined in accordance with GAAP, as appearing on the Borrower's
financial statements.
<PAGE>
 
          Consolidated Net Income shall mean the net income of the Borrower and
          -----------------------                                              
its Subsidiaries determined on a consolidated basis, as determined in accordance
with GAAP, consistently applied.

          Consolidated Net Worth shall mean stockholders' equity of any Person
          ----------------------                                              
determined on a consolidated basis, as determined in accordance with GAAP
consistently applied.

          Consolidated Receivables shall mean the Borrower's and its
          ------------------------                                  
Subsidiaries Receivables consolidated in accordance with GAAP.

          Consolidated Senior Indebtedness shall mean Indebtedness of the
          --------------------------------                               
Borrower and its Subsidiaries consolidated in accordance with GAAP, which
Indebtedness by its terms is not explicitly subordinated in a manner in form and
substance satisfactory to the Agent and the Required Lenders to the payment in
full of the Lender Obligations.

          Consolidated Senior Indebtedness to Consolidated EBITDA Ratio shall
          -------------------------------------------------------------      
mean, as of any date of determination, the ratio of the Borrower's Consolidated
Senior Indebtedness as of the end of the Borrower's most recently completed
Fiscal Quarter to the Borrower's Consolidated EBITDA for the Borrower's four
most recently completed Fiscal Quarters treated as a single accounting period.

          Control shall mean the possession, directly or indirectly, of the
          -------                                                          
power to direct or cause the direction of the management or policies of a
Person, whether through the ownership of voting securities, by contract or
otherwise, including the power to elect a majority of the directors or trustees
of a corporation or trust, as the case may be, and the terms "Controlled" and
                                                             ------------    
"Controlling" shall have correlative meanings.
-------------                                 

          December 1998 Delivery Date shall mean the date on which the annual
          ---------------------------                                        
financial statements described in Section 6.02(b) for the Fiscal Year ending
December 31, 1998, are delivered to the Agent.

          Default shall mean any event or condition which with notice or passage
          -------                                                               
of time or both, would constitute an Event of Default.

          Dollar, Dollars, U.S. Dollars and the symbol $ shall mean lawful money
          -----------------------------                -                        
of the United States of America.

          Dollar Equivalent shall mean, with respect to any amount of any
          -----------------                                              
currency, the Equivalent Amount of such currency expressed in Dollars.

          Environmental Complaint shall mean any written complaint setting forth
          -----------------------                                               
a cause of action for personal or property damage or equitable relief, or any
order, notice of violation or citation issued pursuant to any Environmental Laws
by an Official Body, subpoena or other written notice of any type relating to,
arising out of, or issued pursuant to, any Environmental Laws or any
Environmental Conditions.
<PAGE>
 
          Environmental Conditions shall mean any conditions of the environment,
          ------------------------                                              
including, without limitation, the work place, the ocean, natural resources
(including flora or fauna), soil, surface water, ground water, any actual or
potential drinking water supply sources, substrata or the ambient air, relating
to or arising out of, or caused by the use, handling, storage, treatment,
recycling, generation, transportation, release, spilling, leaking, pumping,
emptying, discharging, injecting, escaping, leaching, disposal, dumping,
threatened release or other management or mismanagement of Regulated Substances
resulting from the use of, or operations on, any of the Property.

          Environmental Laws shall mean all federal, state; local and foreign
          ------------------                                                 
Laws and regulations, including permits, licenses, authorizations, bonds,
orders, judgments and consent decrees issued or entered into pursuant thereto,
relating to pollution or protection of human health or the environment or
employee safety in the work place.

          Equivalent Amount shall mean, at any time, as determined by the Agent
          -----------------                                                    
(which determination shall be conclusive absent manifest error), with respect to
an amount of any currency (the "Reference Currency") which is to be computed as
an equivalent amount of another currency (the "Equivalent Currency"): (i) if the
Reference Currency and the Equivalent Currency are the same, the amount is such
Reference Currency; or (ii) if the Reference Currency and the Equivalent
Currency are not the same, the amount is such Equivalent Currency converted from
such Reference Currency at the Agent's spot selling rate (based on the market
rates then prevailing and available to the Agent) for the sale of such
Equivalent Currency for such Reference Currency at a time determined by the
Agent on the second Business Day immediately preceding the event for which such
calculation is made.

          Equivalent Currency shall have the meaning assigned to such term in
          -------------------                                                
the definition of Equivalent Amount.

          ERISA shall mean the Employee Retirement Income Security Act of 1974,
          -----                                                                
as the same may be amended or supplemented from time to time, and any successor
statute of similar import, and the rules and regulations thereunder, in each
case as from time to time in effect.

          ERISA Group shall mean, at any time, the Borrower and all members of a
          -----------                                                           
controlled group of corporations and all trades or businesses (whether or not
incorporated) under common control and all other entities which, together with
the Borrower, are treated as a single employer under Section 414 of the Internal
Revenue Code.

          Euro shall have the meaning ascribed to it in Section 2.13.
          ----                                                       

          Euro-Rate shall mean:  (A) with respect to any Loans denominated in
          ---------                                                          
Dollars comprising any Portion to which the Euro-Rate Option applies for any
Euro-Rate Interest Period, the interest rate per annum determined by the Agent
by dividing (the resulting quotient rounded upward to the nearest 1/100th of 1%
per annum) (i) the rate of interest determined by the Agent in accordance with
its usual procedures (which determination shall be conclusive and binding upon
the Borrower, absent manifest error on the part of the Agent) to be equal to the
offered rates for deposits in Dollars for the applicable Euro-Rate Interest
Period quoted by the British Bankers Association ("BBA") which appear on Page
3750 of the Dow Jones Market
<PAGE>
 
Service display page (or, if such quotation is not available, an appropriate
successor as determined by the Agent) reporting system as of approximately 11:00
a.m., Greenwich Mean Time, two (2) Business Days prior to the first day of such
Euro-Rate Interest Period for an amount comparable to such Loan and having a
borrowing date and a maturity comparable to such Interest Period by (ii) a
number equal to 1.00 minus the Euro-Rate Reserve Percentage. Such Euro-Rate may
also be expressed by the following formula:

          Euro-Rate  =  Offered rate on Dow Jones Market Service
                        ----------------------------------------
                        1.00 - Euro-Rate Reserve Percentage

If more than one offered rate appears on Page 3750 of the Dow Jones Market
Service rate reporting system or similar system, the rate will be the arithmetic
mean of such offered rates; and

          (B) with respect to any Loans denominated in Optional Currency
comprising any Portion to which the Euro-Rate Option applies for any Euro-Rate
Interest Period, the interest rate per annum determined by Agent by dividing
(the resulting quotient rounded upward to the nearest 1/100th of 1% percent per
annum) (i) the rate of interest per annum determined by Agent in accordance with
its usual procedures (which determination shall be conclusive and binding upon
the Borrower absent manifest error) to be the rate of interest per annum for
deposits in the relevant Optional Currency quoted by BBA which appears on the
relevant Dow Jones Market Service display page (or, if such quotation is not
available, an appropriate successor as determined by the Agent) at approximately
9:00 a.m., Pittsburgh time, two (2) Business Days prior to the first day of such
Interest Period for delivery on the first day of such Interest Period for a
period, and in an amount, comparable to such Interest Period and principal
amount of such disbursement ("LIBO Rate") by (ii) a number equal to 1.00 minus
the Euro-Rate Reserve Percentage.  Such Euro-Rate may also be expressed by the
following formula:

          Euro-Rate  =                 LIBO Rate
                          ----------------------------------
                          1  -  Euro-Rate Reserve Percentage

The Euro-Rate shall be adjusted with respect to any Euro-Rate Option outstanding
on the effective date of any change in the Euro-Rate Reserve Percentage as of
such effective date.  The Agent shall give prompt notice to the Borrower of the
Euro-Rate as determined or adjusted in accordance herewith, which determination
shall be conclusive absent manifest error.  The Euro-Rate for any Loans shall be
based upon the Euro-Rate for the currency in which such Loans are requested.

          Euro-Rate Interest Period shall mean any individual period equal to
          -------------------------                                          
one (1), two (2), three (3), six (6) selected by the Borrower or twelve (12)
months if requested by the Borrower and available to the Agent and the Lenders
in each case commencing on the Borrowing Date, a conversion date or a renewal
date of a Euro-Rate Portion to which such period shall apply; provided, however,
that prior to the date which is the Business Day following the Syndication Date,
only such periods as the Agent and the Borrower mutually agree upon, not to
exceed a period of one month, shall be available.

          Euro-Rate Option shall mean the interest rate option described in
          ----------------                                                 
Section 2.08b(ii) hereof.
<PAGE>
 
          Euro-Rate Portion shall mean each portion of the Loans which bears, or
          -----------------                                                     
is to bear, interest under the Euro-Rate Option; and the term Euro-Rate Portions
shall mean collectively all such portions of the Loans which bear, or are to
bear, interest under the Euro-Rate Option.

          Euro-Rate Reserve Percentage shall mean for any day the maximum
          ----------------------------                                   
effective percentage as determined by the Agent in accordance with its usual
procedures (which determination shall be conclusive absent manifest error) as
prescribed by the Federal Reserve Board (or any successor) for determining the
reserve requirements (including, without limitation, supplemental, marginal and
emergency reserve requirements) with respect to eurocurrency funding (currently
referred to as "Eurocurrency Liabilities") of a member bank in the Federal
Reserve System.

          Event of Default shall have the meaning ascribed to it in Section 8.01
          ----------------                                                      
hereof.

          Expiration Date shall mean November 30, 2003.
          ---------------                              

          Federal Funds Effective Rate shall mean for any day the rate per annum
          ----------------------------                                          
(based on a year of 360 days and actual days elapsed and rounded upward to the
nearest 1/100 of 1 %) announced by the Federal Reserve Bank of New York (or any
successor) on such day (or if such day is not a Business Day, the previous
Business Day) as being the weighted average of the rates on overnight federal
funds transactions with members of the Federal Reserve System arranged by
federal funds brokers on the previous trading day, as computed and announced by
such Federal Reserve Bank (or any successor) in substantially the same manner as
such Federal Reserve Bank computes and announces the weighted average it refers
to as the "Federal Funds Effective Rate" as of the date of this Agreement.

          Federal Reserve Board shall mean the Board of Governors of the United
          ---------------------                                                
States Federal Reserve System as constituted from time to time.

          Fee shall mean any of the Agent's Fee, the Arrangement Fee, the
          ---                                                            
Closing Fee, the Commitment Fee, the Letter of Credit Fee, the L/C Fronting Fee,
any administration fee payable to the Agent, and any other fee payable under any
of the other Loan Documents.

          Fiscal Quarter shall mean each three month fiscal period of the
          --------------                                                 
Borrower beginning respectively on each January 1, April 1, July 1 and October 1
during the term hereof and ending on the immediately succeeding March 31, June
30, September 30 and December 31.

          Fiscal Year shall mean each 12-month fiscal period of the Borrower
          -----------                                                       
beginning January 1 and ending on the immediately succeeding December 31.

          Founding Shareholders shall mean Ashok K. Trivedi and Sunil Wadhwani.
          ---------------------                                                

          GAAP shall mean, subject to the provisions of Section 1.03 hereof,
          ----                                                              
generally accepted accounting principles set forth in the opinions and
pronouncements of the Accounting Principles Board of the American Institute of
Certified Public Accountants and statements and
<PAGE>
 
pronouncements of the Financial Accounting Standards Board or in such other
statements by such other entity as may be recognized by a significant segment of
the accounting profession, which are applicable to the circumstances as of the
date of determination.

          Guaranty or Guarantee shall mean any obligation, direct or indirect,
          ---------------------                                               
by which a Person undertakes to guaranty, assume or remain liable for the
payment of another Person's obligations, including but not limited to (i)
endorsements of negotiable instruments, (ii) discounts with recourse, (iii)
agreements to pay upon a second Person's failure to pay, (iv) agreements to
maintain the capital, working capital solvency or general financial condition of
a second Person and (v) agreements for the purchase or other acquisition of
products, materials, supplies or services, if in any case payment therefor is to
be made regardless of the nondelivery of such products, materials or supplies or
the non-furnishing of such services.

          Indebtedness shall mean as to any Person at any time, any and all
          ------------                                                     
indebtedness, obligations or liabilities (whether matured or unmatured,
liquidated or unliquidated, direct or indirect, absolute or contingent or joint
and several) of such Person for or in respect of: (i) borrowed money, (ii)
amounts raised under or liabilities in respect of any note purchase or
acceptance credit facility, (iii) reimbursement obligations (contingent or
otherwise) under any letter of credit, currency swap agreement, hedging
contracts, Interest Hedge Agreement or other interest rate management device,
raw materials management device or commodities management device (except raw
materials or commodity management devices entered into in the ordinary course of
business), (iv) any other transaction (including forward sale or purchase
agreements, capitalized leases and conditional sales agreements) having the
commercial effect of a borrowing of money entered into by such Person to finance
its operations or capital requirements (but not including trade payables and
accrued expenses incurred in the ordinary course of business which are not
represented by a promissory note or other evidence of indebtedness), or (v) any
Guaranty of any of the foregoing.

          Ineligible Security shall mean any security which may not be
          -------------------                                         
underwritten or dealt in by member banks of the Federal Reserve System under
Section 16 of the Banking Act of 1933 (12 U.S.C. Section 24, Seventh), as
amended.

          Interest Hedge Agreement shall mean any interest rate swap agreement,
          ------------------------                                             
interest rate cap agreement, interest rate collar agreement, interest rate
insurance or any other agreement or arrangement designed to provide protection
against fluctuations in interest rates.

          Interest Rate Option shall mean the Euro-Rate Option or the Base Rate
          --------------------                                                 
Option.

          Internal Revenue Code shall mean the Internal Revenue Code of 1986, as
          ---------------------                                                 
the same may be amended or supplemented from time to time, and any successor
statute of similar import, and the rules and regulations thereunder, as from
time to time in effect.

          L/C Fronting Fee shall have the meaning ascribed to it in Section
          ----------------                                                 
2.18(b) of this Agreement.

          L/C Issuer shall mean PNC Bank, National Association, as the issuer of
          ----------                                                            
Letters of Credit pursuant to Section 2.18, and any successor to PNC Bank,
National Association as the issuer of Letters of Credit hereunder.
<PAGE>
 
          Labor Contracts shall have the meaning ascribed to it in Section 4.19
          ---------------                                                      
hereof.

          Law shall mean any law (including common law), constitution, statute,
          ---                                                                  
treaty, regulation, rule, ordinance, opinion, release, ruling, order,
injunction, writ, decree or award of any Official Body.

          Lender Obligations shall mean collectively, (i) all unpaid principal
          ------------------                                                  
and accrued and unpaid interest under the Loans, (ii) all accrued and unpaid
Fees hereunder or under any of the other Loan Documents, (iii) the face amount
of all Letters of Credit then outstanding, together with all Unreimbursed L/C
Draws and all accrued and unpaid interest on such Unreimbursed L/C Draws, (iv)
the actual (as opposed to nominal) credit exposure determined in accordance with
standard industry practices to any Lender or Affiliate of a Lender under an
Interest Hedge Agreement between such Person and the Borrower, (v) any amounts
due any Lender or an Affiliate of any Lender on any foreign exchange contract,
(vi) any other amounts payable hereunder or under any of the other Loan
Documents, including all reimbursements, indemnities, fees, costs, expenses,
prepayment premiums and other obligations of the Borrower to a Lender (in any
capacity hereunder) or any indemnified party hereunder, (vii) all out-of-pocket
costs and expenses incurred by the Agent in connection with this Agreement or
any other Loan Documents, including but not limited to the reasonable fees and
expenses of the Agent's counsel, (viii) all out-of-pocket costs and expenses
incurred by a Lender after an Event of Default in connection with any
administration or enforcement of the Loan Documents, including but not limited
to the reasonable fees and expenses of such Lender's counsel, and (ix) all other
liabilities, obligations, covenants, duties and Indebtedness of the Borrower to
the Agent, the L/C Issuer and the Lenders of any and every kind and nature,
arising under this Agreement or the other Loan Documents, whether heretofore,
now or hereafter owing, arising, due or payable from the Borrower to the Agent,
the L/C Issuer or the Lenders.

          Lenders shall mean the financial institutions named on Schedule
          -------                                                --------
1.01(a) hereto and their respective successors and assigns as permitted
-------                                                                
hereunder, each of which is referred to herein as a Lender.

          Letter of Credit shall mean any Standby Letter of Credit or Commercial
          ----------------                                                      
Letter of Credit issued by the L/C Issuer for the account of the Borrower upon
the application of the Borrower pursuant to this Agreement and all extensions,
renewals, amendments, substitutions and replacements thereto and thereof.

          Letter of Credit Fee shall have the meaning ascribed to it in Section
          --------------------                                                 
2.18(b) hereof.

          Lien shall mean any mortgage, deed of trust, pledge, lien, security
          ----                                                               
interest, charge or other encumbrance or security arrangement of any nature
whatsoever, whether voluntarily or involuntarily given, including but not
limited to any conditional sale or title retention arrangement, and any
assignment, deposit arrangement or lease intended as, or having the effect of,
security and any filed financing statement or other notice of any of the
foregoing (whether or not a lien or other encumbrance is created or exists at
the time of the filing).
<PAGE>
 
          Loans shall mean collectively all advances and Loan shall mean
          -----                                          ----           
separately any advance made by the Lenders pursuant to Section 2.01 hereof.

          Loan Account shall mean the loan account maintained by a Lender as
          ------------                                                      
more fully described in Section 2.15 hereof.

          Loan Disbursement Account shall have the meaning ascribed to it in
          -------------------------                                         
Section 3.01 hereof.

          Loan Documents shall mean this Agreement, the Notes, any Application
          --------------                                                      
for Letter of Credit, the Subsidiary Guarantees, the Pledge Agreements, any
Interest Rate Hedge Agreement executed by a Lender or an Affiliate of a Lender
and the Borrower, any foreign exchange contract executed by a Lender or an
Affiliate of a Lender and the Borrower, and any other agreements, instruments,
certificates or documents contemplated thereby, as any of the same may be
supplemented or amended from time to time in accordance herewith or therewith;
and Loan Document shall mean any of the Loan Documents.

          Loan Parties shall mean the Borrower, each Subsidiary Guarantor and
          ------------                                                       
each pledgor party to a Pledge Agreement and Loan Party shall mean any of the
                                            -----------                      
Loan Parties.

          Loan Request shall mean a request for Loans made in accordance with
          ------------                                                       
Section 2.05 hereof which request shall be substantially in the form of Exhibit
                                                                        -------
"B" hereto.
---        

          Margin Regulations shall mean Regulations T, U and X as promulgated by
          ------------------                                                    
the Board of Governors of the Federal Reserve System, as amended from time to
time.

          Material Adverse Change shall mean any set of circumstances or events
          -----------------------                                              
which (a) has or could reasonably be expected to have any material adverse
effect upon the validity or enforceability of this Agreement or any of the other
Loan Documents, (b) is or could reasonably be expected to be material and
adverse to the business, properties, assets, financial condition or results of
operations of the Borrower and its Subsidiaries, taken as a whole, (c) impairs
materially or could reasonably be expected to impair materially the ability of
the Borrower and its Subsidiaries taken as a whole to duly and punctually pay
their Indebtedness, or (d) impairs materially or could reasonably be expected to
impair materially the ability of the Agent or any of the Lenders to enforce
their legal remedies pursuant to this Agreement or any other Loan Document.

          Moody's shall mean Moody's Investors Service, Inc., a corporation
          -------                                                          
organized and existing under the laws of the State of Delaware, its successors
and assigns, and, if such corporation shall be dissolved or liquidated or shall
no longer perform the functions of a securities rating agency, "Moody's" shall
be deemed to refer to any other nationally recognized securities rating agency
designated by the Agent, with the approval of the Borrower, by notice to the
Lenders.

          Multiemployer Plan shall mean any employee benefit plan which is a
          ------------------                                                
"multiemployer plan" within the meaning of Section 4001(a)(3) of ERISA and to
which the Borrower or any member of the ERISA Group is then making or accruing
an obligation to make
<PAGE>
 
contributions or, within the preceding five Plan years, has made or had an
obligation to make such contributions.

          Multiple Employer Plan shall mean a Plan which has two or more
          ----------------------                                        
contributing sponsors (including the Borrower or any member of the ERISA Group)
at least two of whom are not under common control, as such a plan is described
in Sections 4063 and 4064 of ERISA.

          Notes shall mean collectively all of the promissory notes of the
          -----                                                           
Borrower substantially in the form of Exhibit "A" hereto and Note shall mean
                                      -----------            ----           
separately each promissory note of the Borrower substantially in the form of
                                                                            
Exhibit "A" hereto in each case evidencing Loans together with all renewals,
-----------                                                                 
replacements, refinancings or refundings thereof or thereto in whole or in part.

          Official Body shall mean any national, federal, state, local or other
          -------------                                                        
government or political subdivision or any agency, authority, bureau, central
bank, commission, department or instrumentality of either, or any court,
tribunal, grand jury or arbitrator, in each case whether foreign or domestic.

          Optional Currency shall mean any of the following currencies:  (a) the
          -----------------                                                     
Australian dollar, (b) the British Pound Sterling, (c) the Canadian dollar, (d)
the French Franc, (e) the Deutsche Mark, (f) the Italian Lira and (g) the
Spanish Pesetas, and any other freely convertible foreign currency, as
determined pursuant to the currency codes in effect from time to time under ISO
International Standard 4217 or any successor thereto, and approved by Agent and
the Required Lenders pursuant to Section 2.13(d).

          Original Currency shall have the meaning assigned to such term in
          -----------------                                                
Section 2.21.

          Other Currency shall have the meaning assigned to such term in Section
          --------------                                                        
2.21.

          Other Taxes shall have the meaning assigned to it in Section 2.19.
          -----------                                                       

          Overnight Rate shall mean for any day with respect to any Loans in an
          --------------                                                       
Optional Currency, the rate of interest per annum as determined by the Agent at
which overnight deposits in such currency, in an amount approximately equal to
the amount with respect to which such rate is being determined, would be offered
for such day in the applicable offshore interbank market.

          Participant shall mean any bank or financial institution which
          -----------                                                   
acquires from any Lender an undivided interest in the Lender' s Ratable Share of
the Revolving Credit Commitments, Loans, Letters of Credit and Unreimbursed L/C
Draws, pursuant to Section 10.05.

          Participation shall mean the sale, made in accordance with the
          -------------                                                 
provisions of Section 10.05, by any Lender to any Participant of an undivided
interest in such Lender's Ratable Share of the Revolving Credit Commitments,
Loans, Letters of Credit and Unreimbursed L/C Draws.
<PAGE>
 
          PBGC shall mean the Pension Benefit Guaranty Corporation established
          ----                                                                
pursuant to Subtitle A of Title IV of ERISA or any successor.

          Permitted Liens shall mean:
          ---------------            

          (i) Liens for taxes, assessments, governmental levies or similar
charges incurred in the ordinary course of business and which are not yet due
and payable, or if due and payable, (aa) are being contested in good faith and
by appropriate and lawful proceedings diligently conducted, but only so long as
such proceedings could not subject the Agent, the Lenders or the L/C Issuer to
any civil or criminal penalties or liabilities and (bb) for which such reserves
or other appropriate provisions, if any, as shall be required by GAAP shall have
been made and (cc) which shall be paid in accordance with the terms of any final
judgments or orders relating thereto within thirty (30) days after the entry of
such judgments or orders;

          (ii) Pledges or deposits made in the ordinary course of business to
secure payment of workmen's compensation, or to participate in any fund in
connection with workmen's compensation, unemployment insurance, old-age
pensions, other social security programs or similar program or to secure
liability to insurance carriers under insurance or self insurance agreements or
arrangement;

          (iii)  Liens of mechanics, materialmen, warehousemen, carriers, or
other like Liens, securing obligations incurred in the ordinary course of
business that are not yet due and payable and Liens of landlords securing
obligations to pay lease payments that are not yet due and payable or in
default, or if such Liens are due and payable, (aa) are being contested in good
faith and by appropriate and lawful proceedings diligently conducted and (bb)
for which such reserves or other appropriate provisions, if any, as required by
GAAP shall have been made and (cc) which shall be paid in accordance with the
terms of any final judgments or orders relating thereto within thirty (30) days
after the entry of such judgments or orders;

          (iv) Pledges or deposits made in the ordinary course of business to
secure performance of bids, tenders, contracts (other than for the repayment of
borrowed money) or leases, not in excess of the aggregate amounts due
thereunder, or to secure statutory obligations, or surety, appeal, indemnity,
performance or other similar bonds required in the ordinary course of business;

          (v) (aa) Encumbrances consisting of zoning restrictions, easements,
rights-of-way, or other restrictions on the use of real property, (bb) defects
in title to real property, and (cc) Liens, encumbrances and title defects
affecting real property not known by the Borrower or a Subsidiary, as
applicable, and not discoverable by a search of the public records, none of
which materially impairs the use of such property;

          (vi) (aa) Liens on assets of a Person which is merged into or acquired
by the Borrower or a Subsidiary of the Borrower on or after the date of this
Agreement, and (bb) Liens on assets acquired after the date of this Agreement,
                                                                              
provided that (A) such Liens existed at the time of such merger or acquisition
--------                                                                      
and were not created in anticipation thereof, (B) no such Lien is spread to
cover any property or assets of the Borrower or any Subsidiary of the Borrower;
and (C) the principal amount of Indebtedness secured thereby is not increased
from the amount outstanding immediately prior to such merger or acquisition;
<PAGE>
 
          (vii)  Liens created by or resulting from any litigation or legal
proceedings which are currently being contested in good faith by appropriate and
lawful proceedings diligently conducted and for which such reserves or other
appropriate provisions, if any, as shall be required by GAAP shall have been
made and Liens arising out of judgments or orders for the payment of money which
do not constitute an Event of Default hereunder;

          (viii)  Liens placed upon fixed assets or equipment hereafter acquired
to secure all or a portion of the purchase price thereof, provided that any such
Lien shall not encumber any other property of the Borrower or any Subsidiary;

          (ix) Other Liens incidental to the conduct of the Borrower's or any
Subsidiary's business or the ownership of its property and assets which were not
incurred in connection with the borrowing of money or the obtaining of advances
or credit, and which do not in the aggregate materially detract from the value
of the Borrower's or any Subsidiary's property or assets or which do not
materially impair the use thereof in the operation of the Borrower's business;

          (x) Leases or subleases not otherwise prohibited by this Agreement or
other Loan Documents; provided, however, except as set forth in items (i)
                      --------  -------                                  
through (x) of this definition the Borrower shall not permit or authorize Liens
on any of the Borrower's or any of its Subsidiaries' properties, except in favor
of the Agent for the benefit of the Agent, the Lenders and the L/C Issuer; and

          (xi) Liens securing Indebtedness of a foreign Subsidiary which
Indebtedness is permitted hereunder; provided such Lien encumbers only the
                                     --------                             
assets of the Subsidiary incurring such Indebtedness.

          Person or person shall mean any individual, corporation, partnership,
          ----------------                                                     
limited liability company, association, joint-stock company, trust,
unincorporated organization, joint venture, government or political subdivision
or agency thereof, or any other entity.

          Plan shall mean at any time an employee pension benefit plan
          ----                                                        
(including a Multiple Employer Plan but not a Multiemployer Plan) which is
covered by Title IV of ERISA or is subject to the minimum funding standards
under Section 412 of the Internal Revenue Code and either (i) is maintained by
any member of the ERISA Group for employees of any member of the ERISA Group or
(ii) has at any time within the preceding five years been maintained by any
entity which was at such time a member of the ERISA Group for employees of any
entity which was at such time a member of the ERISA Group.

          Pledge Agreement shall mean a pledge agreement executed by the
          ----------------                                              
Borrower or another Loan Party substantially in the form of Exhibit "D" hereto,
                                                           ------------        
together in each case with all extensions, renewals, amendments, substitutions,
and replacements thereto and thereof.

          Portions shall mean collectively the Base Rate Portions and the Euro-
          --------                                                            
Rate Portions; and the term Portion shall mean individually any of the Portions.
                            -------                                             
<PAGE>
 
          Prime Rate shall mean for any day, a fluctuating interest rate per
          ----------                                                        
annum equal to the rate of interest which the Agent announces from time to time
as its prime lending rate, which rate may not be the lowest rate then being
charged by the Agent to commercial borrowers.

          Principal Office shall mean the principal commercial banking office of
          ----------------                                                      
the Agent in Pittsburgh, Pennsylvania.

          Prohibited Transaction shall mean any prohibited transaction as
          ----------------------                                         
defined in Section 4975 of the Internal Revenue Code or Section 406 of ERISA for
which neither an individual nor a class exemption has been issued by the United
States Department of Labor.

          Property shall mean, and refer to, each parcel of real property,
          --------                                                        
whether owned in fee or leased, of any Loan Party.

          Purchasing Lender shall mean a Lender which becomes a party to this
          -----------------                                                  
Agreement by executing an Assignment and Assumption Agreement.

          Ratable Share shall mean the proportion that a Lender's Revolving
          -------------                                                    
Credit Commitment bears to the Revolving Credit Commitments of all of the
Lenders.

          Receivable shall mean, with respect to the Borrower or any Subsidiary,
          ----------                                                            
all accounts receivable, contract rights related to such account receivable,
instruments, chattel paper, general intangibles related to such Receivables and
all other rights to payments of moneys for any reason (whether or not evidenced
by a contract, instrument, chattel paper or document), and all other rights,
powers and privileges of the Borrower or any Subsidiary, as the case may be,
arising thereunder or related thereto (including but not limited to all
guarantees, collateral security, surety bonds, rights under letters of credit,
insurance or other direct or indirect security), assertible against any Person
whatever and all rebates, refunds, adjustments and returned, rejected, or
repossessed goods relating thereto and all proceeds of any of the foregoing.

          Reference Currency shall have the meaning assigned to such term in the
          ------------------                                                    
definition of Equivalent Amount.

          Register shall have the meaning ascribed to it in Section 10.05(c).
          --------                                                           

          Regulated Substances shall mean any substance, including without
          --------------------                                            
limitation Solid Waste, the generation, manufacture, processing, distribution,
treatment, storage, disposal, transport, recycling, reclamation, use, reuse or
other management or mismanagement of which is regulated by the Environmental
Laws.

          Reportable Event shall mean a reportable event described in Section
          ----------------                                                   
4043 of ERISA and regulations thereunder with respect to a Plan or Multiemployer
Plan.

          Required Lenders shall mean Lenders whose Revolving Credit Commitments
          ----------------                                                      
aggregate at least 66-2/3% of the Revolving Credit Commitments of all of the
Lenders.
<PAGE>
 
          Revolving Credit Commitment shall mean, as to any Lender at any time,
          ---------------------------                                          
the aggregate amount initially set forth opposite its name on Schedule 1.01(a),
                                                              ---------------- 
and thereafter on Schedule I to the most recent Assignment and Assumption
Agreement, as the same may be reduced pursuant to Sections 2.04 or 2.10(a)
hereof, and Revolving Credit Commitments shall mean the aggregate Revolving
            ----------------------------                                   
Credit Commitments of all of the Lenders.

          S&P shall mean Standard & Poor's Ratings Group, a division of McGraw
          ---                                                                 
Hill Corporation, and, if such corporation shall be dissolved or liquidated or
shall no longer perform the functions of a securities rating agency, "S&P" shall
be deemed to refer to any other nationally recognized securities rating agency
designated by the Agent, with the approval of the Borrower, by notice to the
Lenders.

          Section 20 Subsidiary shall mean the Subsidiary of the bank holding
          ---------------------                                              
company controlling any Lender, which Subsidiary has been granted authority by
the Federal Reserve Board to underwrite and deal in certain Ineligible
Securities.

          Solid Waste shall mean any garbage, refuse or sludge from any waste
          -----------                                                        
treatment plant, water supply treatment plant or air pollution control facility
generated by activities on the Property, and any unpermitted release into the
environment or the work place of any material as a result of activities on the
Property, including without limitation used Regulated Substances.

          Solvent shall mean, with respect to any Person on a particular date,
          -------                                                             
that on such date (i) the fair value of the property of such Person is greater
than the total amount of liabilities, including, without limitation, contingent
liabilities, of such Person, (ii) the present fair salable value of the assets
of such Person is not less than the amount that will be required to pay the
probable liability of such Person on its debts as they become absolute and
matured, (iii) such Person is able to realize upon its assets and pay its debts
and other liabilities, contingent obligations and other commitments as they
mature in the normal course of business, (iv) such Person does not intend to,
and does not believe that it will, incur debts or liabilities beyond such
Person's ability to pay as such debts and liabilities mature, and (v) such
Person is not engaged in business or a transaction, and is not about to engage
in business or a transaction, for which such Person's property would constitute
unreasonably small capital after giving due consideration to the prevailing
practice in the industry in which such Person is engaged. In computing the
amount of contingent liabilities at any time, it is intended that such
liabilities will be computed at the amount which, in light of all the facts and
circumstances existing at such time, represents the amount that can reasonably
be expected to become an actual or matured liability.

          Standby Letter of Credit shall mean a letter of credit which is not a
          ------------------------                                             
Commercial Letter of Credit.

          Standby Letter of Credit Fee shall have the meaning ascribed to it in
          ----------------------------                                         
Section 2.18(b) hereof.

          Stated Amount shall mean as to any Letter of Credit, the lesser of (i)
          -------------                                                         
the face amount thereof or (ii) the remaining available undrawn amount thereof
(regardless of whether any conditions for drawing could then be met).
<PAGE>
 
          Subsidiary of any Person at any time shall mean (i) any corporation or
          ----------                                                            
trust of which 50% or more (by number of shares or number of votes) of the
outstanding capital stock or shares of beneficial interest normally entitled to
vote for the election of one or more directors or trustees (regardless of any
contingency which does or may suspend or dilute the voting rights) is at such
time owned directly or indirectly by such Person or one or more of such Person's
Subsidiaries, (ii) any partnership of which such Person is a general partner or
of which 50% or more of the partnership interests is at the time directly or
indirectly owned by such Person or one or more of such Person's Subsidiaries,
(iii) any limited liability company of which such Person is a member or of which
50% or more of the limited liability company interests is at the time directly
or indirectly owned by such Person or one or more of such Person's Subsidiaries
or (iv) any corporation, trust, partnership, limited liability company or other
entity which is Controlled or capable of being Controlled by such Person or one
or more of such Person's Subsidiaries.

          Subsidiary Guarantor shall mean each Subsidiary of the Borrower
          --------------------                                           
incorporated or organized in the United States of America whether now existing
or hereafter created or acquired.

          Subsidiary Guaranty shall mean a guaranty agreement executed by a
          -------------------                                              
Subsidiary Guarantor substantially in the form of Exhibit "C" attached hereto,
                                                  -----------                 
together in each case with all extensions, renewals, amendments, substitutions
and replacements thereto and thereof.

          Syndication Date shall mean the earlier of (i) the date of completion
          ----------------                                                     
of syndication hereunder, as determined by the Agent, or (ii) ninety (90) days
after the Closing Date.

          Taxes shall have the meaning ascribed to it in Section 2.19.
          -----                                                       

          Total Utilization shall mean as of the time of determination the sum
          -----------------                                                   
of Loans outstanding, the Unreimbursed L/C Draws outstanding and the aggregate
Stated Amount of the Letters of Credit outstanding.

          Transfer Effective Date shall have the meaning ascribed to it in the
          -----------------------                                             
applicable Assignment and Assumption Agreement.

          Transferor Lender shall mean the selling Lender pursuant to an
          -----------------                                             
Assignment and Assumption Agreement.

          Unreimbursed L/C Draw shall have the meaning ascribed to it in Section
          ---------------------                                                 
2.18(f).

          Year 2000 Problem shall have the meaning ascribed to it in Section
          -----------------                                                 
4.25.

          1.02.  Construction.
                 ------------ 

          (a) Unless the context of this Agreement otherwise clearly requires,
the following rules of construction shall apply to this Agreement and each of
the other Loan Documents:
<PAGE>
 
          (i) Number: Inclusion. References to the plural include the singular,
              -----------------                                                
the singular the plural and the part the whole, "or" has the inclusive meaning
represented by the phrase "and/or," and "including" has the meaning represented
by the phrase "including without limitation".

          (ii) Determination. References to "determination" of or by the Agent,
               -------------                                                   
the L/C Issuer or the Lenders shall be deemed to include good faith estimates by
the Agent, the L/C Issuer or the Lenders (in the case of quantitative
determinations) and good faith beliefs by the Agent, the L/C Issuer or the
Lenders (in the case of qualitative determinations) and such determination shall
be conclusive absent manifest error.

          (iii)  Discretion and Consent. Whenever the Agent, the L/C Issuer, PNC
                 ----------------------                                         
Bank or the Lenders are granted the right herein to act in its or their sole
discretion or to grant or withhold consent such right shall be exercised in good
faith.

          (iv) Documents Taken as a Whole. The words "hereof," "herein,"
               --------------------------                               
"hereunder", "hereto" and similar terms in this Agreement or any other Loan
Document refer to this Agreement or such other Loan Document as a whole and not
to any particular provision of this Agreement or such other Loan Document.

          (v) Headings. The article, section and other headings contained in
              --------                                                      
this Agreement or such other Loan Documents and the Table of Contents (if any)
preceding this Agreement or such other Loan Document are for reference purposes
only and shall not control or affect the construction of this Agreement or such
other Loan Document or the interpretation thereof in any respect.

          (vi) Implied References. Article, section, subsection, item, clause,
               ------------------                                             
schedule and exhibit references are to this Agreement or to such other Loan
Document, as the case may be, unless otherwise specified.

          (vii)  Persons. Reference to any Person includes such Person's
                 -------                                                
successors and assigns, but, if applicable, only if such successors and assigns
are permitted by this Agreement or such other Loan Document, as the case may be,
and reference to a Person in a particular capacity excludes such Person in any
other capacity.

          (viii)  Laws and Agreements. Reference to any Law, agreement or
                  -------------------                                    
contract includes such Law, agreement or contract as the same may be amended,
supplemented, modified, extended, waived, consolidated, replaced or renewed from
time to time, but only to the extent permitted by, and effected in accordance
with, the terms thereof and of this Agreement and the other Loan Documents.

          (ix) From, To and Through. Relative to the determination of any period
               --------------------                                             
of time, "from" means "from and including", "to" means "to but excluding", and
"through" means "through and including".

          (x) Shall; Will. References to "shall" and "will" are intended to have
              -----------                                                       
the same meaning.
<PAGE>
 
          (xi) UCC Terms. All terms used in Article 9 of the Uniform Commercial
               ---------                                                       
Code and not specifically defined in this Agreement or in any other Loan
Document shall herein have the meanings assigned to such terms in the Uniform
Commercial Code as from time to time in effect in the Commonwealth of
Pennsylvania.

          (xii)  Writing; Written. References to "writing" include printing,
                 ----------------                                           
typing, lithography and other means of reproducing words in a tangible visible
form. References to "written" include "printed", "typed", "lithographed" and
other adjectives relating to words reproduced in a tangible visible form
consistent with the preceding sentence and also include electronic images and
images stored on computer disks, magnetic tape and like media.

          1.03.  Accounting Principles  . Except as otherwise provided in this
                 ---------------------                                        
Agreement, all computations and determinations as to accounting or financial
matters and all financial statements to be delivered pursuant to this Agreement
shall be made and prepared in accordance with GAAP (including principles of
consolidation where appropriate), and all accounting or financial terms shall
have the meanings ascribed to such terms by GAAP.

                                   ARTICLE II
                           REVOLVING CREDIT FACILITY
                           -------------------------

          2.01.  Revolving Credit Commitments  . Subject to the terms and
                 ----------------------------                            
conditions hereof and relying upon the representations and warranties herein set
forth, each Lender severally agrees to make Loans (the "Loans") in Dollars or
Optional Currency to the Borrower at any time or from time to time on or after
the date hereof to, but not including, the Expiration Date, provided that the
aggregate principal Equivalent Amount in Dollars of each Lender's Loans
outstanding hereunder to the Borrower shall not exceed at any one time such
Lender's Ratable Share of the aggregate Revolving Credit Commitments minus such
Lender's Ratable Share of the sum of (i) the aggregate Stated Amount of
outstanding Letters of Credit and (ii) the aggregate amount of Unreimbursed L/C
Draws. Within such limits of time and amount and subject to the other provisions
of this Agreement, the Borrower may borrow, repay and reborrow pursuant to this
Section 2.01. The aggregate amount of the Revolving Credit Commitments on the
Closing Date is $75,000,000. All Revolving Credit Commitments shall expire on
the Expiration Date; and all Loans outstanding on the Expiration Date shall
become due and payable in full on such date.

          2.02.  Nature of Lenders' Obligations with Respect to Loans.   Each
                 ----------------------------------------------------        
Lender shall be obligated to participate in each request for Loans pursuant to
Section 2.05 hereof in accordance with its Ratable Share. The aggregate
principal Equivalent Amount in Dollars of each Lender's Loans outstanding
hereunder to the Borrower at any time shall never exceed such Lender's Ratable
Share of the aggregate Revolving Credit Commitments minus such Lender's Ratable
Share of the sum of (i) the aggregate Stated Amount of outstanding Letters of
Credit and (ii) the aggregate amount of Unreimbursed L/C Draws. The obligations
of each Lender hereunder are several. The failure of any Lender to perform its
obligations hereunder shall not affect the obligations of the Borrower, or any
other Lender, to any other party nor shall the Borrower, or any other Lender, be
liable for the failure of such Lender to perform its obligations hereunder. The
Lenders shall have no obligation to make Loans hereunder on or after the
Expiration Date.
<PAGE>
 
          2.03.  Commitment Fees
                 ---------------

          (a) Commitment Fee.  Accruing from the Closing Date until the
              --------------                                           
Expiration Date, the Borrower agrees to pay to the Agent for the account of each
Lender, as consideration for such Lender's Revolving Credit Commitment
hereunder, a commitment fee (the "Commitment Fee") equal to the Applicable
Commitment Fee per annum, as determined below, (all computed on the basis of a
year of 365 or 366 days, as the case may be, and actual days elapsed) on the
average daily Equivalent Amount in Dollars equal to such Lender's Revolving
Credit Commitment minus such Lender's Ratable Share of Total Utilization
relating to its Revolving Credit Commitment.

          (b) Applicable Commitment Fee.  For purposes of this Agreement, the
              -------------------------                                      
term "Applicable Commitment Fee" shall mean the rate per annum set forth in the
chart below which corresponds to the range of ratios in which the Borrower's
Consolidated Senior Indebtedness to Consolidated EBITDA Ratio, as at the end of
the preceding fiscal quarter, falls:

<TABLE>
<CAPTION>
                   Consolidated Senior Indebtedness
                     to Consolidated EBITDA Ratio                             Commitment Fee
------------------------------------------------------------------------------------------------
<S>                                                                      <C>
Less than 0.5 to 1.0                                                               .15%
------------------------------------------------------------------------------------------------
Equal to or greater than 0.5 to 1.0, but less than 1.0 to 1.0
                                                                                  .175%
------------------------------------------------------------------------------------------------
Equal to or greater than 1.0 to 1.0 but less than or equal to 1.5 to
 1.0                                                                               .20%
 
------------------------------------------------------------------------------------------------
Equal to or greater than 1.5 to 1.0 but less than or equal to 2.0 to
 1.0                                                                               .225%
 
------------------------------------------------------------------------------------------------
Equal to or greater than 2.0 to 1.0                                                .25%
------------------------------------------------------------------------------------------------
</TABLE>

All such adjustments shall be determined as of the date the Borrower's financial
statements and Compliance Certificate are required to be delivered to the
Lenders pursuant to items (a), (b) and (c) of Section 6.02. The foregoing
notwithstanding, the Applicable Commitment Fee from the Closing Date to and
including the December 1998 Delivery Date shall be .15%. All Commitment Fees
shall be payable (i) quarterly in arrears beginning December 31, 1998, and
continuing on the last Business Day of each Fiscal Quarter occurring during the
term of the Revolving Credit Commitment, (ii) upon the Expiration Date and (iii)
upon acceleration of the Notes.

          2.04.  Reduction of Revolving Credit Commitment.   Subject to the
                 ----------------------------------------                  
provisions of Section 2.09 hereof, at any time and from time to time upon at
least five (5) Business Days' prior written notice to the Agent, the Borrower
may terminate, in whole or in part, without penalty, the then unused portion of
the Revolving Credit Commitments, thereby causing a corresponding abatement of
the Commitment Fee. Each such reduction shall be in a minimum principal amount
of $10,000,000 or, if in excess of $10,000,000, in integral multiples of
$1,000,000. The Commitment Fee shall cease to accrue with respect to any unused
portion of the Revolving Credit Commitments so terminated five (5) Business Days
after receipt of such notice. Notice of termination once given shall be
irrevocable and the portion of the Revolving Credit Commitments so terminated
shall not be available for borrowing once such notice has been given under the
terms hereof. The Agent shall promptly notify each Lender of its Ratable Share
of such terminated unused portion and the date of each such termination.
<PAGE>
 
          2.05.  Loan Requests  . Each request for a disbursement shall be made
                 -------------                                                 
to the Agent by an Authorized Officer of the Borrower orally or in writing
pursuant to the execution and delivery by the Borrower to the Agent of a Loan
Request, substantially in the form of Exhibit "B" hereto, (A) by 11:00 a.m.
                                      -----------                          
(Pittsburgh, Pennsylvania time) on the date of the proposed disbursement if the
disbursement is initially to bear interest at the Base Rate Option, (B) by 11:00
a.m. (Pittsburgh, Pennsylvania time) at least three (3) Business Days prior to
the proposed disbursement with respect to Loans made in Dollars if the
disbursement or any part thereof is to initially bear interest at the Euro-Rate
Option, or (C) by 11:00 a.m. (Pittsburgh, Pennsylvania time) at least four (4)
Business Days prior to the proposed disbursement with respect to Loans funded in
an Optional Currency (which Loans must bear interest at the Euro-Rate Option),
in each case specifying the date and the Dollar or Dollar Equivalent (if
applicable) amount thereof, selecting the Interest Rate Option therefor pursuant
to Section 2.08(b) hereof, for Loans to be funded under the Euro-Rate Option,
selecting the Euro-Rate Interest Period therefor and for Loans to be funded in
an Optional Currency, the currency in which the disbursement is to be funded.
Any oral request for a disbursement hereunder shall be followed immediately by
the Borrower's written Loan Request. A request from the Borrower pursuant to
this Section 2.05 with respect to a disbursement or any part thereof which is
initially to bear interest at the Euro-Rate Option, shall irrevocably commit the
Borrower to accept such disbursement on the date specified in such request.
Promptly upon receipt of such notice, the Agent shall notify each Lender of the
Borrower's request and the amount of such requested disbursement which is to be
advanced by such Lenders.  Each such Lender shall make its Ratable Share of such
disbursement available at the Agent's principal office in immediately available
funds no later than 3:00 p.m. (Pittsburgh, Pennsylvania time) on the date of the
requested disbursement.

          2.06.  Making Loans  . Subject to Section 9.03, the Agent shall,
                 ------------                                             
promptly after receipt by it of a Loan Request pursuant to Section 2.05 (but not
later than noon (Pittsburgh, Pennsylvania time) on the Borrowing Date for same
day funding, 2:00 p.m. (Pittsburgh, Pennsylvania time) on the third Business Day
preceding any Borrowing Date for which any Portion of the Loans to be made on
such Borrowing Date is to bear interest at the Euro-Rate Option and 2:00 p.m.
(Pittsburgh, Pennsylvania time) on the fourth Business Day preceding any
Borrowing Date of the Loans to be made in an Optional Currency), notify the
Lenders of its receipt of such Loan Request specifying: (i) the proposed
Borrowing Date and the time and method of disbursement of such Loan; (ii) the
amount and type of such Loan and the applicable Euro-Rate Portions and Euro-Rate
Interest Periods (if any) and the Optional Currency (if any); and (iii) the
apportionment among the Lenders of the Loans as determined by the Agent in
accordance with Section 2.02 hereof. Subject to Section 9.03, each Lender shall
remit the principal amount of each Loan to the Agent such that the Agent is able
to, and the Agent shall, to the extent the Lenders have made funds available to
it for such purpose, fund such Loan to the Borrower in immediately available
funds prior to 2:00 P.M. (Pittsburgh, Pennsylvania time) on the Borrowing Date,
provided that if any Lender fails to remit such funds to the Agent in a timely
manner, or any Lender fails to advise the Agent of its intention not to fund,
then the Agent may elect in its sole discretion to fund with its own funds the
Loan of such Lender on the Borrowing Date.

          2.07.  Notes.   The obligation of the Borrower to repay the aggregate
                 -----                                                         
unpaid principal amount of the Loans made to the Borrower by each Lender,
together with interest
<PAGE>
 
thereon, shall be evidenced by a promissory note of the Borrower dated the
Closing Date in substantially the form attached hereto as Exhibit "A" payable to
                                                          ----------
the order of each Lender in a face amount equal to the Revolving
Credit Commitment of such Lender.

          2.08.  Interest Payments, Interest Rates and Certain Related Payments
                 --------------------------------------------------------------
Pertaining to the Loans.
-----------------------   

          (a) Interest. The Notes shall bear interest on the actual unpaid
              --------                                                    
principal amount thereof from time to time outstanding from the date thereof
until payment in full at the rates of interest set forth in Section 2.08(b). The
Borrower shall pay accrued interest on the unpaid principal balance of the Notes
in arrears:

              (i) with respect to the Base Rate Portion, at the rate specified
in the Base Rate Option, (A) on the last Business Day of each Fiscal Quarter
during the term of the Revolving Credit Commitment, (B) at maturity, whether by
acceleration or otherwise, of the Notes and (C) after maturity on demand until
all amounts evidenced by the Notes are paid in full whether or not judgment has
been entered on the Notes; and

              (ii) with respect to each Euro-Rate Portion, at the rate specified
in the Euro-Rate Option, (A) on the last day of the Euro-Rate Interest Period
applicable thereto; provided, however, if the Euro-Rate Interest Period chosen
                    --------  ------- 
for any Euro-Rate Portion exceeds three (3) months, interest on that Euro-Rate
Portion shall be due and payable at the end of every three (3) months during
such Euro-Rate Interest Period and on the last day of such Euro-Rate Interest
Period, (B) at the maturity, whether by acceleration or otherwise, of the Notes
and (C) after maturity on demand until all amounts evidenced by the Notes are
paid in full whether or not judgment has been entered on the Notes.

          (b) Interest Rate Options. During the term hereof, the Borrower shall
              ---------------------                                            
have the option of electing, from time to time, one or more of the Interest Rate
Options set forth below to be applied to the Loans.

              (i) Base Rate Option. Interest under this Interest Rate Option
                  ----------------
shall accrue, for the Base Rate Portion of the Loans outstanding, at a rate per
annum equal to the Base Rate. The Base Rate shall be adjusted automatically from
time to time upon each change in the Prime Rate or the Federal Funds Effective
Rate, as the case may be, and in accordance with the provisions of Section
2.08(d).

              (ii) Euro-Rate Option. Interest under this Interest Rate Option
                   ----------------
shall accrue, for each Euro-Rate Portion of the Loans outstanding, for any Euro-
Rate Interest Period selected, at a rate per annum equal to the sum of (A) the
Euro-Rate plus (B) the Applicable Euro-Rate Margin as determined below. The rate
of interest established pursuant to the preceding sentence of this Section
2.08(b)(ii) for each Euro-Rate Portion shall be adjusted from time to time in
accordance with the provisions of Section 2.08(d).

For purposes of this Agreement, the term "Applicable Euro-Rate Margin" shall
mean the rate per annum set forth in the chart below which corresponds to the
range of ratios in which the Borrower's Consolidated Senior Indebtedness to
Consolidated EBITDA Ratio as at the end of the preceding Fiscal Quarter falls:
<PAGE>
 
<TABLE>
<CAPTION>
                          Consolidated Senior Indebtedness                                Applicable Euro-Rate
                            to Consolidated EBITDA Ratio                                         Margin
------------------------------------------------------------------------------------------------------------------
<S>                                                                                   <C>
Less than 0.5 to 1.0                                                                              .50%
------------------------------------------------------------------------------------------------------------------
Equal to or greater than 0.5 to 1.0 but less than 1.0 to 1.0
                                                                                                  .625%
------------------------------------------------------------------------------------------------------------------
Equal to or greater than 1.0 to 1.0 but less than 1.5 to 1.0
                                                                                                   .75%
------------------------------------------------------------------------------------------------------------------
Equal to or greater than 1.5 to 1.0 but less than 2.0 to 1.0
                                                                                                  .875%
------------------------------------------------------------------------------------------------------------------
Equal to or greater than 2.0 to 1.0                                                               1.00%
------------------------------------------------------------------------------------------------------------------
</TABLE>

All adjustments shall be determined as of the date the Borrower's financial
statements and Compliance Certificate are required to be delivered pursuant to
items (a), (b) and (c) of Section 6.02.  The foregoing notwithstanding, the
Applicable Euro-Rate Margin from the Closing Date to and including the December
1998 Delivery Date shall be .50%.

          (c) Optional Currency Interest.  Each Portion of each Optional
              --------------------------                                
Currency funded Loan shall bear interest at the Euro-Rate Option, subject,
however, to the other provisions of this Agreement.

          (d) Interest After Maturity. After the occurrence of an Event of
              -----------------------                                     
Default and during the continuation thereof, the Base Rate Portion shall bear
interest at a rate per annum which shall be two hundred (200) basis points (2%)
above the Base Rate otherwise in effect during such period. After the occurrence
of an Event of Default and during the continuation thereof, all Euro-Rate
Portions shall bear interest (i) until the end of the then current Euro-Rate
Interest Period for each such Euro-Rate Portion, at a rate per annum which shall
be two hundred (200) basis points (2%) above the sum of (A) the Euro-Rate and
(B) the Applicable Euro-Rate Margin otherwise in effect during such period and
(ii) at the end of the then current Euro-Rate Interest Period for each such
Euro-Rate Portion, such Euro-Rate Portions shall automatically be converted to
the Base Rate Portion, and thereafter the interest rate shall be calculated in
accordance with the initial sentence of this Section 2.08(d).

          (e) Interest Periods; Limitations on Elections. At any time when the
              ------------------------------------------                      
Borrower shall select, convert to or renew the Euro-Rate Option to apply to all
or any portion of the outstanding Loans, it shall elect one or more Euro-Rate
Interest Periods as the case may be. All the foregoing, however, is subject to
the following:

              (i) any Euro-Rate Interest Period which would otherwise end on a
day which is not a Business Day shall be extended to the next Business Day
unless such Business Day falls in the succeeding calendar month in which case
such Euro-Rate Interest Period shall end on the next preceding Business Day; and

              (ii) any Euro-Rate Interest Period which begins on the last day of
a calendar month or on a day for which there is no numerically corresponding day
in the subsequent calendar month during which such Euro-Rate Interest Period is
to end shall end on the last Business Day of such subsequent month.
<PAGE>
 
Elections by the Borrower of the Euro-Rate Option shall be subject to the
following limitations:

              (i) The Euro-Rate Portion for each Euro-Rate Interest Period shall
be in an aggregate principal Equivalent Amount of $1,000,000 or more; provided,
                                                                      --------
however, that each increment in excess of $1,000,000 shall be $1,000,000 or an
-------
integral multiple thereof;

              (ii) No Euro-Rate Interest Period may be elected at any time that
a Default or an Event of Default shall have occurred and be continuing;

              (iii)  No Euro-Rate Interest Period may be elected which would end
later than the relevant Expiration Date;

              (iv) No Euro-Rate Interest Period may be elected with regard to
amounts outstanding which would be in excess of the Revolving Credit Commitment;
and

              (v) At no time may there be more than seven (7) separate Euro-Rate
Interest Periods in effect.

          (f) Election, Renewal or Conversion of Interest Rate Options.
              -------------------------------------------------------- 
Elections or renewals of, or conversions to, the Base Rate Option shall continue
in effect until converted or renewed as hereinafter provided. Elections or
renewals of, or conversions to, the Euro-Rate Option shall expire as to each
Euro-Rate Portion at the expiration of the applicable Euro-Rate Interest Period.
At any time with respect to the Base Rate Portion or at the expiration of the
applicable Euro-Rate Interest Period with respect to any Euro-Rate Portion, the
Borrower may cause (subject to Subsection 2.08(e)) all or any part of the
principal amount of such Portion to be converted to, or to be renewed under, the
Euro-Rate Option by notice to the Agent as hereinafter provided. Such notice (i)
shall be irrevocable, (ii) shall be given not later than noon (Pittsburgh,
Pennsylvania time) in the case of a conversion to or renewal of, either in whole
or in part, the Euro-Rate Option, not less than three (3) Business Days prior to
the proposed effective date for such conversion or renewal, and (iii) shall set
forth:

          (A) the effective date of such conversion or renewal, which
shall be a Business Day;

          (B) the new Euro-Rate Interest Period(s) selected; and

          (C) with respect to each such Euro-Rate Interest Period, the
aggregate principal amount of the corresponding Euro-Rate Portion.

At the expiration of each Euro-Rate Interest Period, any part (including the
whole) of the principal amount of the corresponding Euro-Rate Portion as to
which no notice of conversion or renewal has been received shall automatically
be converted to the Base Rate Option. The Agent shall promptly notify the
Borrower and the Lenders of any such automatic conversion.

          (g) Notification of Election of an Interest Rate Option. The Borrower,
              ---------------------------------------------------               
by an Authorized Officer, shall notify the Agent of each election of an Interest
Rate Option, each conversion from one Interest Rate Option to another, the
amount of the Loans then outstanding
<PAGE>
 
to be allocated to each Interest Rate Option and, where relevant, the Euro-Rate
Interest Periods as provided for in this Agreement. Any such communication may
be oral or written and if oral it shall be followed promptly by written
confirmation of such Interest Rate Option election executed by an Authorized
Officer of the Borrower.

          (h) Calculation of Interest. Interest on the Base Rate Portion shall
              -----------------------                                         
be calculated on the basis of a 365 or 366 day year, as the case may be, and the
actual days elapsed. Interest on each Euro-Rate Portion shall be calculated on
the basis of a 360-day year and the actual days elapsed. The calculation of the
amount of interest due and owing to the Lenders shall be evidenced by posting
the amount of interest due under the Revolving Credit Notes to the Loan Account
established by the Agent pursuant to Section 2.15.

          (i) Lawful Interest Rates Intended. In no event whatsoever shall the
              ------------------------------                                  
interest rates charged hereunder exceed the highest rate permissible under any
law which a court of competent jurisdiction shall, in a final determination,
deem applicable hereto. In the event that such a court determines that any
Lender has received interest hereunder in excess of the highest applicable rate,
such Lender shall promptly refund such excess to the Borrower, or at such
Lender's option, apply such excess in reduction of the principal balance of the
Lender Obligations owing to the affected Lender.

          2.09.  Prepayments: Allocation of Repayments.
                 ------------------------------------- 

          (a) Prepayments of Base Rate Portion. The Borrower, upon oral or
              --------------------------------                            
written notice to the Agent by an Authorized Officer of Borrower given not later
than 12:00 noon (Pittsburgh, Pennsylvania time) on the proposed date for
prepayment, may prepay without penalty or premium any or all of the Base Rate
Portion. Any oral notice of election hereunder shall be followed immediately by
written confirmation of such prepayment election executed by an Authorized
Officer of Borrower.

          (b) Prepayments of Euro-Rate Portions. Except as otherwise provided in
              ---------------------------------                                 
Section 2.10(c), the Borrower, upon oral or written notice to the Agent by an
Authorized Officer of Borrower given at least three (3) Business Days prior to
the proposed date for repayment, may prepay, all or any part of such Euro-Rate
Portion. If such Euro-Rate Portion is prepaid on the last day of the Euro-Rate
Interest Period applicable thereto, such prepayment shall be without premium or
penalty. If the Borrower prepays a Euro-Rate Portion other than on the last day
of the Euro-Rate Interest Period applicable thereto, the Borrower agrees to pay,
in addition to the other amounts set forth in this Section 2.09(b), such
additional amounts as may be necessary to compensate each Lender for any loss
(including loss of profit on a pre-tax basis) and any direct or indirect costs,
including the costs of reemployment of funds prepaid at rates lower than the
cost to such Lender of such funds. Such losses and costs shall be specified in
writing to the Borrower by the affected Lenders (and such specifications shall
set forth in reasonable detail the calculation of such losses and costs) and
such specifications shall, absent manifest error, be binding and conclusive on
the Borrower. Such prepayment shall include the then outstanding principal
Equivalent Amount in Dollars of the Euro-Rate Portion being prepaid together
with accrued interest, fees and other amounts then due and payable on the amount
prepaid, to the day of such prepayment. Except as provided in this Section
2.09(b), there shall be no voluntary prepayment of any Euro-Rate Portion.
<PAGE>
 
          (c) Allocation of Repayments of Principal. Except as otherwise
              -------------------------------------                     
specified by the Borrower, any voluntary prepayment pursuant to this Section
2.09 hereof shall be applied first to the repayment of any Euro-Rate Portion of
the Loans for which its associated Euro-Rate Interest Period expires on the date
of such payment, second, to the reduction of the Base Rate Portion of the Loans,
and third, to the reduction of such Euro-Rate Portions of the Loans as directed
by the Borrower, and if the Borrower fails to give such directions, or if a
Default or Event of Default has occurred and is continuing, to the reduction of
such Euro-Rate Portions of the Loans as the Agent may select in its sole and
absolute discretion. Any reduction in any Euro-Rate Portion on a date other than
the date on which its associated Euro-Rate Interest Period expires may result in
a funding loss for which the Borrower will owe the Lenders an indemnity payment
pursuant to Section 2.10 hereof.

          2.10.  Yield Protection.
                 ----------------   

          (a) If any change subsequent to the Closing Date in any Law or in the
interpretation or application thereof by any Official Body or in the compliance
with any guideline or request from any Official Body, shall make it unlawful for
any Lender to maintain or give effect to its obligations as contemplated under
the Revolving Credit Commitment, such Lender shall notify the Borrower and the
Agent in writing of its determination of such unlawfulness and an explanation
thereof. Thereafter, such Lender's obligation to make available any further
Loans hereunder shall forthwith be cancelled and the Borrower, within thirty
(30) days, or within such longer period as may be allowed by Law, if any, shall
repay to such Lender so affected its pro rata share of the outstanding principal
amount of all Loans, together with interest thereon to the date of repayment and
fees, if any, due as of the date of termination; provided, however, that the
affected Lender's obligations which are lawful, if severable from those which
are unlawful, shall continue, and with respect to those obligations, this
Agreement shall not terminate.

          (b) If any Law issued after the Closing Date (including, without
limitation, Regulation D of the Federal Reserve Board), or if any change on or
after the Closing Date in any Law (including, without limitation, Regulation D)
or in the interpretation thereof by any Official Body charged with the
administration thereof, shall

              (i) subject any Lender to any tax, levy, impost, charge, fee,
duty, deduction or withholding or any kind hereunder (other than any tax imposed
or based upon the income of such Lender and payable to any governmental or
taxing authority in the United States of America, any state or any municipality
thereof); or

              (ii) change the basis of taxation of any Lender with respect to
payments of principal or interest or other amounts due hereunder (other than any
change which affects, and only to the extent that it affects, the taxation by
the United States, any state or any municipality thereof based upon the income
of such Lender); or

              (iii) impose, modify or deem applicable any reserve, special
deposit or similar requirements against assets held by any Lender (other than
such requirements which result solely from a change in the credit quality of the
Borrower or which are included in the determination of the applicable rate of
interest hereunder); or
<PAGE>
 
              (iv) impose upon any Lender any other obligation or condition
with respect to this Agreement, and the result of any of the foregoing is to
increase the cost to any Lender, to decrease the yield to any Lender with
respect to the Loans or any Letters of Credit, to reduce the income receivable
by any Lender or to impose any expenses upon any Lender with respect to the
Loans or any Letters of Credit by an amount which any Lender reasonably deems
material, then and in any such case:

          (A) the Lender so affected shall promptly notify the Borrower and the
Agent of the happening of such event;

          (B) the Borrower shall pay to the affected Lender, within five (5)
Business Days of written demand such amount as will compensate such Lender for
such additional cost or reduced amount, calculated from the date of the
notification by such Lender; and

          (C) the Borrower may pay to such affected Lender the affected Loan in
full without the payment of any additional amount other than on account of such
Lender's out-of-pocket losses (including funding losses, if any, as provided in
paragraph (c) below) not otherwise provided for in subparagraph (B) immediately
above.

The Lender so affected shall present to the Borrower and the Agent a certificate
setting forth such increased cost or reduced amount. Such certificate shall set
forth in reasonable detail the calculation of the amount due and such Lender's
reasons for invoking the provisions of this Section 2.10(b). Such certificate
shall be conclusive evidence of the amount due thereunder except in the case of
manifest error in computation.

          (c) The Borrower agrees to indemnify each Lender, on demand, against
any loss or expense (including loss of profit) which such Lender may sustain or
incur in liquidating or employing deposits from third parties acquired to
effect, fund or maintain such Euro-Rate Portions or any part thereof as a
consequence of (i) the failure of the Borrower to make a payment on the due date
thereof, (ii) the failure of the Borrower to borrow under, convert to or renew
under the Euro-Rate Option on the proposed effective date of such borrowing,
conversion or renewal, or (iii) the payment, prepayment or conversion by the
Borrower of any Euro-Rate Portions for any reason on a day other than the last
day of the applicable Euro-Rate Interest Period. Any Lender's determination of
an amount payable under this paragraph (c) shall be conclusive absent manifest
error.

          (d) The foregoing notwithstanding, if the affected Lender can mitigate
or eliminate such increased cost or reduced yield by transferring the Loans to
another existing lending office of such Lender, such Lender agrees to so
transfer the Loans; provided, such transfer would not subject such Lender to any
                    --------                                                    
unreimbursed cost or expense and would not otherwise be disadvantageous to such
Lender.

          2.11.  Special Provisions Relating to the Euro-Rate Option.  -
                 ---------------------------------------------------   -

          (a) Euro-Rate Unascertainable. In the event that on any date on which
              -------------------------                                        
a Euro-Rate Option would otherwise be set, the Agent shall have determined
(which determination shall be final and conclusive) that, by reason of
circumstances affecting the
<PAGE>
 
London interbank market, adequate, reasonable means do not exist for
ascertaining the Euro-Rate, the Agent shall give prompt notice of such
determination to the Borrower and the Lenders. Until the Agent notifies the
Borrower and the Lenders that the circumstances giving rise to such
determination no longer exist (which notice shall be given promptly following
receipt of knowledge thereof by the Agent), the right of the Borrower to borrow
under, convert to or renew the Euro-Rate Option shall be suspended. Any notice
of borrowing under, conversion to or renewal of the Euro-Rate Option which was
to become effective during the period of such suspension shall be treated as a
request to borrow under, convert to or renew the Base Rate Option with respect
to the principal amount therein specified.

          (b) Inability to Offer Euro-Rate. In the event that any Lender shall
              ----------------------------                                    
determine, in its sole discretion, that it is unable to obtain deposits in the
London interbank market in sufficient amounts and with maturities related to
such Euro-Rate Portions which would enable such Lender to fund such Euro-Rate
Portions, then such Lender shall notify the Borrower and the Agent that the
right of the Borrower to borrow under, convert to or renew the Euro-Rate Option,
shall be suspended with respect to such Lender. Such notice shall set forth in
reasonable detail such Lender's reasons for invoking the provisions of this
Section 2.11(b). Following notification of the suspension of the Euro-Rate
Option with respect to such Lender, the Borrower agrees to negotiate with such
Lender for a modified or alternative fixed rate of interest, which will allow
such Lender to realize its anticipated and bargained-for yield. In the event
that the Borrower and such Lender cannot agree on a modified or alternative
fixed rate of interest, any notice of borrowing under, conversion to or renewal
of the Euro-Rate Option which was to become effective during the period of
suspension shall be treated as a request to borrow under, convert to or renew
the Base Rate Option with respect to the principal amount specified therein
attributable to such Lender.

          (c) Illegality. If any Lender shall determine in good faith (which
              ----------                                                    
determination shall be final and conclusive) that compliance with any Law
(whether or not having the force of law) or the interpretation or application
thereof by any Official Body, has made it unlawful or impractical for such
Lender to make or maintain the Loans under the Euro-Rate Option, such Lender
shall give notice of such determination to the Borrower and the Agent, which
notice shall set forth in reasonable detail such Lender's reasons for invoking
the provisions of this Section 2.11(c). Notwithstanding any provision of this
Agreement to the contrary, unless and until such Lender shall have given notice
to the Borrower and the Agent that the circumstances giving rise to such
determination no longer apply (which notice shall be given promptly following
receipt of knowledge thereof by such Lender):

              (i) with respect to any Euro-Rate Interest Periods thereafter
commencing, interest in an amount equal to such Lender's Ratable Share of the
corresponding Euro-Rate Portion shall be computed and payable under the Base
Rate Option; and

              (ii) on such date, if any, as shall be required by law, an amount
equal to such Lender's Ratable Share of any Euro-Rate Portion, as the case may
be, then outstanding shall be automatically converted to the Base Rate Option
and the Borrower shall pay to such Lender the accrued and unpaid interest on
such amounts to (but not including) such conversion date.
<PAGE>
 
The Borrower shall pay any such Lender any additional amounts reasonably
necessary to compensate such Lender for any costs incurred by such Lender as a
result of any conversion pursuant to clause (ii) above which occurs on a day
other than the last day of the relevant Euro-Rate Interest Period, including,
but not limited to, any interest or fees payable by such Lender to lenders of
funds obtained by them to loan or maintain the lending of the Loans so
converted. Such Lender shall furnish to the Borrower and the Agent a certificate
as to the amount necessary to compensate it for such costs, which certificate
shall set forth in reasonable detail the calculation of the amount due. Such
certificate shall constitute conclusive evidence of the amount due thereunder
absent any manifest error in computation. The Borrower shall pay such amount to
such Lender, as additional consideration hereunder, within ten (10) days of the
Borrower's receipt of such certificate.

          (d) The foregoing notwithstanding, if the affected Lender can continue
to offer the Euro-Rate Option to the Borrower by transferring the Loans to
another existing lending office of such Lender, such Lender agrees to so
transfer the Loans; provided, such transfer would not subject such Lender to any
                    --------                                                    
unreimbursed cost or expense and would not otherwise be disadvantageous to such
Lender.

          2.12.  Capital Adequacy. If after the Closing Date (i) any adoption
                 ----------------                                              
of or any change in or in the interpretation by an Official Body of any Law or
(ii) compliance with any Law, guideline or request of any Official Body
exercising control over banks or financial institutions generally or any court
(whether or not having the force of law), affects or would affect the amount of
capital required or expected to be maintained by any Lender or any corporation
controlling such Lender other than those resulting solely from a change in the
credit quality of the Borrower (a "Capital Adequacy Event"), and the result of
such Capital Adequacy Event is to reduce the rate of return on capital of such
Lender or any corporation controlling such Lender as a consequence thereof to a
level below that which such Lender could have achieved but for such Capital
Adequacy Event, taking into consideration such Lender's policies with respect to
capital adequacy, by an amount which such Lender deems to be material, such
Lender shall promptly deliver to the Borrower and the Agent a statement of the
amount necessary to compensate such Lender for the reduction in the rate of
return on its capital attributable to the commitments under this Agreement or
any of the Loan Documents (the "Capital Compensation Amount").  Each Lender
shall determine the Capital Compensation Amount in good faith, using reasonable
attribution and averaging methods.  Each Lender shall, from time to time,
furnish to the Borrower and the Agent a certificate setting forth the amount so
determined and the calculations of such amount.  Such certificate shall
constitute conclusive evidence of the amount due thereunder absent any manifest
error in computation.  Such amount shall be due and payable by the Borrower to
such Lender ten (10) days after such notice is given.  As soon as practicable
after any Capital Adequacy Event, such Lender shall submit to the Borrower and
the Agent estimates of the Capital Compensation Amounts that would be payable as
a function of such Lender's Revolving Credit Commitment hereunder.

          2.13.  Utilization of Commitments in Optional Currencies.
                 -------------------------------------------------   

          (a) Periodic Computations of Dollar Equivalent Amounts of Loans and
              ---------------------------------------------------------------
Letters of Credit Outstanding.  The Agent will determine the Dollar Equivalent
-----------------------------                                                 
amount of (i) proposed Loans or Letters of Credit to be denominated in an
Optional Currency as of the date of the requested disbursement or date of
issuance, as the case may be, (ii) outstanding Loans
<PAGE>
 
or Letters of Credit Outstanding denominated in an Optional Currency as of the
last Business Day of each month, and (iii) outstanding Loans denominated in an
Optional Currency as of the end of each Interest Period (each such date under
clauses (i) through (iii), a "Computation Date").

          (b) Notices From Lenders That Optional Currencies Are Unavailable To
              ----------------------------------------------------------------
Fund New Loans.  The Lenders shall be under no obligation to make the Loans or
--------------                                                                
issue the Letters of Credit requested by the Borrower which are denominated in
an Optional Currency if any Lender notifies the Agent by 5:00 p.m. (Pittsburgh,
Pennsylvania time) four (4) Business Days prior to the borrowing or issuance
date for such Loans or Letters of Credit that such Lender cannot provide its
share of such Loans in such Optional Currency.  In the event the Agent timely
receives a notice from a Lender pursuant to the preceding sentence, the Agent
will notify the Borrower no later than 12:00 Noon (Pittsburgh, Pennsylvania
time) three (3) Business Days prior to the disbursement for such Loans or the
issuance of such Letter of Credit that the Optional Currency is not then
available for such Loans or such Letters of Credit, and the Agent shall promptly
thereafter notify the Lenders of the same.  If the Borrower receives a notice
described in the preceding sentence, the Borrower may, by notice to the Agent
not later than 5:00 p.m. (Pittsburgh, Pennsylvania time) three (3) Business Days
prior to the borrowing or issuance date for such Loans or such Letters of
Credit, withdraw the Loan Request for such Loans or the issuance of such Letters
of Credit.  If the Borrower withdraws such Loan Request, the Agent will promptly
notify each Lender of the same and the Lenders shall not make such Loans or
issue such Letters of Credit.  If the Borrower does not withdraw such Loan
Request before such time, (i) the Borrower shall be deemed to have requested
that (a) the Loans referred to in its Loan Request shall be made in Dollars in
an amount equal to the Dollar Equivalent amount of such Loans and (b) the
Letters of Credit referred to in its Loan Request shall be issued in Dollars in
an amount equal to the Dollar Equivalent amount of such Letters of Credit and
shall bear interest under the Base Rate Option, and (ii) the Agent shall
promptly deliver a notice to each Lender stating:  (A) that such Loans or such
Letters of Credit shall be made in Dollars and the Loans shall bear interest
under the Base Rate Option, (B) the aggregate amount of such Loans or such
Letters of Credit, and (C) such Lender's Ratable Share of such Loans or such
Letters of Credit.

          (c) Notices from Lenders that Optional Currencies Are Unavailable to
              ----------------------------------------------------------------
Fund Renewals of Euro-Rate Option Loans.  If the Borrower delivers a Loan
---------------------------------------                                  
Request requesting that the Lenders renew the Euro-Rate Option with respect to
an outstanding Portion of Loans or Letters of Credit denominated in an Optional
Currency, the Lenders shall be under no obligation to renew such Euro-Rate
Option if any Lender delivers to the Agent a notice by 5:00 p.m. (Pittsburgh,
Pennsylvania time) four (4) Business Days prior to effective date of such
renewal that such Lender cannot continue to provide Loans or Letters of Credit
in such Optional Currency.  In the event the Agent timely receives a notice from
a Lender pursuant to the preceding sentence, the Agent will notify the Borrower
no later than 12:00 Noon (Pittsburgh time) three (3) Business Days prior to the
renewal date that the renewal of such Loans or such Letters of Credit in such
Optional Currency is not then available, and the Agent shall promptly thereafter
notify the Lenders of the same.  If the Agent shall have so notified the
Borrower that any such continuation of Loans denominated in an Optional Currency
or Letters of Credit issued in an Optional Currency is not then available, any
notice of renewal with respect thereto shall be deemed withdrawn, and such Loans
denominated in an Optional Currency or Letters of Credit issued in an Optional
Currency shall be re-denominated into Base Rate Loans or Letters of
<PAGE>
 
Credit in Dollars with effect from the last day of the Interest Period with
respect to any such Loans denominated in an Optional Currency or Letters of
Credit issued in an Optional Currency. The Agent will promptly notify the
Borrower and the Lenders of any such re-denomination, and in such notice, the
Agent will state the aggregate Dollar Equivalent amount of the re-denominated
Loans denominated in an Optional Currency or Letters of Credit issued in an
Optional Currency as of the Computation Date with respect thereto and such
Lender's Ratable Share thereof.

          (d) Requests for Additional Optional Currencies.  The Borrower may
              -------------------------------------------                   
deliver to the Agent a written request that Loans hereunder also be permitted to
be made in any other lawful currency (other than Dollars), in addition to the
currencies specifically identified in the definition of "Optional Currency";
provided that such currency must be freely traded in the offshore interbank
foreign exchange markets, freely transferable, freely convertible into Dollars
and available to the Lenders in the applicable interbank market.  The Agent will
promptly notify the Lenders of any such request promptly after the Agent
receives such request.  Each Lender may grant or deny such request in its sole
discretion.  The Agent will promptly notify the Borrower of the acceptance or
rejection by each of the Lender of the Borrower's request.  The requested
currency shall be approved as an Optional Currency hereunder only if the
Required Lenders approve of the Borrower's request.

          (e) Optional Currency Fee.  The Borrower shall pay to the Agent in
              ---------------------                                         
Dollars for the Agent's sole account the Agent's then in effect customary fees
and administrative expenses payable with respect to Loans denominated in an
Optional Currency or Letters of Credit issued in an Optional Currency as the
Agent may generally charge or incur in connection with the funding, maintenance,
modification (if any), assignment or transfer (if any), negotiation, and
administration of Loans denominated in an Optional Currency or Letters of Credit
issued in an Optional Currency.

          (f) Currency Repayments.  Notwithstanding anything contained herein to
              -------------------                                               
the contrary, the entire amount of principal of and interest on any Loan made in
an Optional Currency shall be repaid in the same Optional Currency in which such
Loan was made, provided, however, that if it is impossible or illegal for the
               --------  -------                                             
Borrower to effect payment of a Loan in the Optional Currency in which such Loan
was made, or if the Borrower defaults in its obligation to do so, the Lenders
may at their option permit such payment to be made (i) at and to a different
location, subsidiary, affiliate or correspondent of the Agent, or (ii) in the
Equivalent Amount of Dollars or (iii) in an Equivalent Amount of such other
currency (freely convertible into Dollars) as the Lenders may solely at their
option designate.  Upon any events described in (i) through (iii) of the
preceding sentence, the Borrower shall make such payment and the Borrower agrees
to hold each Lender harmless from and against any loss incurred by any Lender
arising from the cost to such Lender of any premium, any costs of exchange, the
cost of hedging and covering the Optional Currency in which such Loan was
originally made, and from any change in the value of Dollars, or such other
currency, in relation to the Optional Currency that was due and owing.  Such
loss shall be calculated for the period commencing with the first day of the
Interest Period for such Loan and continuing through the date of payment
thereof.  Without prejudice to the survival of any other agreement of the
Borrower hereunder, the Borrower's obligations under this Section 2.13 shall
survive termination of this Agreement.
<PAGE>
 
          (g) Optional Currency Amounts.  Notwithstanding anything contained
              -------------------------                                     
herein to the contrary, the Agent may, with respect to notices by the Borrowers
for Loans in an Optional Currency or voluntary prepayments of less than the full
amount of an Optional Currency Disbursement, engage in reasonable rounding of
the Optional Currency amounts requested to be loaned or repaid; and, in such
event, the Agent shall promptly notify the Borrower and the Lenders of such
rounded amounts and the Borrower's request or notice shall thereby be deemed to
reflect such rounded amounts.

          (h) Currency Fluctuations.  If on any Computation Date the sum of the
              ---------------------                                            
Dollar Equivalent of all Loans and all Letters of Credit Outstanding is greater
than the sum of the Revolving Credit Commitments, as a result of a change in
exchange rates between one (1) or more Optional Currencies and Dollars, then the
Agent shall notify the Borrower of the same. Within one (1) Business Day after
receiving such notice, the Borrower shall either (i) pay or prepay (subject to
the Borrower's indemnity obligations under this Agreement) Loans denominated in
an Optional Currency and Letters of Credit issued in an Optional Currency or
(ii) pay or prepay Loans denominated in Dollars (subject to the Borrower's
indemnity obligations under this Agreement), in either case in amounts such that
the sum of the Dollar Equivalent of all Loans and all Letters of Credit
Outstanding does not exceed the Revolving Credit Commitments, all after giving
effect to such payments or prepayments.

          (i)  European Monetary Union.
               ----------------------- 

              (i) (A) If, as a result of the implementation of the European
monetary union, any Optional Currency ceases to be lawful currency of the nation
issuing the same and is replaced by a European common currency (the "Euro") or
(B) any Optional Currency and the Euro are at the same time recognized by any
governmental authority of the nation issuing such currency as lawful currency of
such nation and the Required Lenders shall so request in a notice delivered to
the Borrower, then any amount payable hereunder by any party hereto in such
Optional Currency shall instead be payable in the Euro and the amount so payable
shall be determined by translating the amount payable in such Optional Currency
to the Euro at the exchange rate recognized by the European Central Bank for the
purpose of implementing the European monetary union. Prior to the occurrence of
the event or events described in clause (A) or (B) of the preceding sentence,
each amount payable hereunder in any Optional Currency will, except as otherwise
provided herein, continue to be payable only in that Optional Currency.

              (ii) The Borrower agrees, at the request of any Lender, to
compensate such Lender for any loss, cost, expense or reduction in return that
such Lender shall reasonably determine shall be incurred or sustained by such
Lender as a result of the implementation of the European monetary union and that
would not have been incurred or sustained but for the transactions provided for
herein. A certificate of the Lender setting forth the Lender's determination of
the amount or amounts necessary to compensate such Lender shall be delivered to
the Borrower, and shall be conclusive absent manifest error so long as such
determination is made on a reasonable basis. The Borrower shall pay such Lender
the amount shown as due on any such certificate within ten (10) days after
receipt thereof.

              (iii)  The parties hereto agree, at the time of or at any time
following the implementation of the European monetary union, to use reasonable
efforts to
<PAGE>
 
enter into an agreement amending this Agreement in order to reflect
the implementation of such monetary union, to permit (if feasible) the Euro to
qualify as an Optional Currency under the terms and conditions of the definition
of such term and to place the parties hereto in the position with respect to the
settlement of payments of the Euro as they would have been with respect to the
settlement of the Optional Currencies it replaced.

          2.14.  Interbank Market Presumption.  For all purposes of this
                 ----------------------------                             
Agreement and each Note with respect to any aspects of the Euro-Rate, any Loan
under the Euro-Rate Option or any Optional Currency, each Lender and the Agent
shall be presumed to have obtained rates, funding, currencies, deposits, and the
like in the applicable interbank market regardless whether it did so or not;
and, each Lender's and the Agent's determination of amounts payable under, and
actions required or authorized by this Agreement shall be calculated, at each
Lender's and the Agent's option, as though each Lender and the Agent funded each
Portion of Loans under the Euro-Rate Option through the purchase of deposits of
the types and maturities corresponding to the deposits used as a reference in
accordance with the terms hereof in determining the Euro-Rate applicable to such
Loans, whether in fact that is the case.

          2.15  Loan Account. The Agent shall open and maintain on its books a
                ------------                                                    
Loan Account in the name of the Borrower, with respect to (i) Loans made,
repayments and prepayments of the principal thereof, and the computation and
payment of interest thereon, (ii) Letters of Credit issued, or participated in,
as the case may be, and draws and reimbursements thereon or thereof, and (iii)
the computation and payment of the Fees due hereunder to the Lenders, the L/C
Issuer and the Agent, and the computation of other amounts due and sums paid to
the Agent hereunder.  Upon the request of the Borrower to the Agent, the Agent
shall promptly furnish to the Borrower a statement of the Loan Account. The
failure to record any such amount shall not limit or otherwise affect the
obligations of the Borrower hereunder or under the Notes to repay all amounts
owed hereunder and thereunder together with all interest accrued thereon and all
other fees and charges provided herein. The Loan Account shall be conclusive
evidence as to the amount at any time due to the Lenders, the L/C Issuer and the
Agent from the Borrower except in the case of manifest error.

          2.16.  All Advances to Constitute One Loan. Notwithstanding the
                 -----------------------------------                       
limitations set forth herein, all Loans and all other Lender Obligations shall
constitute one loan and all Indebtedness and obligations of the Borrower to the
Lenders under this Agreement and all other Loan Documents shall constitute a
general obligation of the Borrower. The parties hereto agree that all of the
rights of the Agent, the L/C Issuer, the Lenders and the Borrower set forth in
this Agreement and the other Loan Documents shall apply to any amendment or
modification of or supplement to this Agreement and the other Loan Documents.

          2.17.  Use of Proceeds. The proceeds of the Loans shall be used
                 ---------------                                           
exclusively (i) to pay interest, Fees and other costs, and expenses hereunder
and under the other Loan Documents, (ii) to repay any Unreimbursed L/C Draw and
(iii) to fund capital expenditures, working capital, acquisitions and general
corporate purposes of the Borrower and its Subsidiaries.  No proceeds of any
Loan may be used for any purpose which contravenes applicable law or any
provision of any Loan Document.

          2.18.  Letter of Credit Subfacility.
                 ----------------------------   
<PAGE>
 
          (a) At the request of the Borrower, the L/C Issuer will issue for the
account of the Borrower and its Subsidiaries, on the terms and conditions
hereinafter set forth (including without limitation Article V hereof), one or
more Letters of Credit in Dollars or Optional Currency; provided, however, no
                                                        --------  -------    
Letter of Credit shall have an expiry date later than the earlier of twelve (12)
months from the date of issuance or fifteen (15) days prior to the Expiration
Date; and provided, further, however, that in no event shall (i) the Dollar
          --------  -------  -------                                       
Equivalent of the Stated Amount of the Letters of Credit issued pursuant to this
Section 2.18 exceed, at any one time, $10,000,000 minus the unpaid balance of
                                                  -----                      
any unreimbursed L/C Draws, or (ii) the Dollar Equivalent sum of aggregate
outstanding principal balance of the Loans, the aggregate unpaid balance of any
Unreimbursed L/C Draws and the aggregate Stated Amount of the Letters of Credit
issued by the L/C Issuer under this Section 2.18 exceed, at any one time, the
aggregate Revolving Credit Commitments.

          (b)  (i)  The Borrower shall pay (A) to the L/C Issuer for its own
account a fronting fee in Dollars equal to 1/8 of 1% per annum (the "L/C
Fronting Fee") on the aggregate daily (computed at the opening of business and
on the basis of a year of 360 days and actual days elapsed) Stated Amount of the
outstanding Standby Letters of Credit for the period in question, (B) to the
Agent for the ratable account of the Lenders a fee (the "Standby Letter of
Credit Fee") equal to the Applicable Standby Letter of Credit Fee per annum, as
determined below, on the aggregate daily (computed at the opening of business
and on the basis of a year of 360 days and actual days elapsed) Stated Amount of
the outstanding Letters of Credit for the period in question, and (C) to the
Agent for the ratable account of the Lenders a fee (the "Commercial Letter of
Credit Fee") equal to the then current standard fee charged by the L/C Issuer
for the issuance of Commercial Letters of Credit (the Standby Letter of Credit
Fee and the Commercial Letter of Credit Fee shall be collectively referred to as
the "Letter of Credit Fee"). The Letter of Credit Fee and the L/C Fronting Fee
shall be payable (A) quarterly in arrears on the last Business Day of each
Fiscal Quarter occurring during the term of this Agreement, (B) on the
Expiration Date or (C) upon acceleration of the Notes. Any issuance of an
amendment to extend the stated expiration date of a Letter of Credit or an
amendment to increase the Stated Amount of a Letter of Credit shall be treated
as an issuance of a new Letter of Credit for purposes of calculation of the
Letter of Credit Fee and the L/C Fronting Fee due and payable hereunder. After
the occurrence of an Event of Default and during the continuation thereof, the
rate at which the Letter of Credit Fee is calculated shall be increased by two
hundred (200) basis points (2%) above the pre-default rate.

              (ii) The Borrower shall also pay to the L/C Issuer for the L/C
Issuer's own account the L/C Issuer's customary documentation fees payable with
respect to the Letters of Credit as the L/C Issuer may generally charge from
time to time.  Without limitation, the foregoing shall include all charges and
expenses paid or incurred by the L/C Issuer in connection with any Letter of
Credit, including without limitation:  (A) correspondents' charges, if any, (B)
any and all reasonable out-of-pocket expenses and charges of the L/C Issuer in
connection with the performance, administration, interpretation, collection and
enforcement of this Agreement and any Letter of Credit, including all reasonable
legal fees and expenses, and (C) any and all applicable reserve or similar
requirements and any and all premiums, assessments, or levies imposed upon the
L/C Issuer by any Official Body.

              (iii) If by reason of (A) any change in any Law or any change in
the interpretation or application by any judicial or regulatory authority of any
Law which
<PAGE>
 
occurs after the date hereof or (B) compliance by the L/C Issuer with any
direction, request or requirement which occurs after the date hereof (whether or
not having the force of law) of any Official Body:

               (1) the L/C issuer shall be subject to any tax, levy, charge or
withholding of any nature or to any variation thereof or to any penalty with
respect to the maintenance or fulfillment of its obligations under this Section
2.18, whether directly or by such being imposed on or suffered by the L/C
Issuer;

              (2) any reserve, deposit or similar requirement is or shall be
applicable, imposed or modified in respect of the Letters of Credit; or

              (3) there shall be imposed on the L/C Issuer any other condition
regarding this Section 2.18 or the Letters of Credit;

and if the result of any of the foregoing is to directly or indirectly increase
the cost to the L/C Issuer of issuing or maintaining any Letter of Credit, or to
reduce the amount receivable in respect thereof by, the L/C Issuer, then and in
any such case the L/C Issuer may, at any time after the additional cost is
incurred or the amount receivable is reduced, notify the Borrower and the Agent,
and the Borrower shall pay on demand such amounts as the L/C Issuer may specify
to be necessary to compensate the L/C Issuer for such additional cost or reduced
receipt, together with interest on such amount from the date of the notice of
such event which results in such increased cost or reduction in amount
receivable until payment in full thereof at a rate equal at all times to the
Base Rate.  The determination by the L/C Issuer of any amount due pursuant to
this Subsection 2.18(b)(iii) as set forth in a certificate setting forth the
calculation thereof, shall, in the absence of manifest error, be final and
conclusive and binding on all of the parties hereto.

For purposes of this Agreement, the term "Applicable Standby Letter of Credit
Fee" shall mean the rate per annum set forth in the chart below which
corresponds to the range of ratios in which the Borrower's Consolidated Senior
Indebtedness to Consolidated EBITDA Ratio as at the end of the preceding Fiscal
Quarter falls:

<TABLE>
<CAPTION>
                   Consolidated Senior Indebtedness                          Applicable Letter of
                     to Consolidated EBITDA Ratio                                 Credit Fee
-----------------------------------------------------------------------------------------------------
<S>                                                                      <C>
Less than 0.5 to 1.0                                                                  .50%
-----------------------------------------------------------------------------------------------------
Equal to or greater than 0.5 to 1.0 but less than 1.0 to 1.0
                                                                                     .625%
-----------------------------------------------------------------------------------------------------
Equal to or greater than 1.0 to 1.0 but less than or equal to 1.5 to
 1.0                                                                                  .75%
 
-----------------------------------------------------------------------------------------------------
Equal to or greater than 1.5 to 1.0 but less than or equal to 2.0 to
 1.0                                                                                 .875%
 
-----------------------------------------------------------------------------------------------------
Equal to or greater than 2.0 to 1.0                                                  1.00%
-----------------------------------------------------------------------------------------------------
</TABLE>

All adjustments shall be determined as of the date the Borrower's financial
statements and Compliance Certificate are required to be delivered pursuant to
items (a), (b) and (c) of Section 6.02.  The foregoing notwithstanding, the
Applicable Letter of Credit Fee from the Closing Date to and including the
December 1998 Delivery Date shall be .50%.
<PAGE>
 
          (c) Immediately upon the issuance of each Letter of Credit and each
increase in the Stated Amount thereof, each Lender hereby agrees to irrevocably
purchase and shall be deemed to have irrevocably purchased from the L/C Issuer
an undivided, full risk, non-recourse participation in such Letter of Credit and
drawings thereunder in an amount equal to such Lender's Ratable Share of the
maximum amount which is or at any time may become available to be drawn
thereunder. In the event that the L/C Issuer is required for any reason to
refund or repay to the Borrower, any guarantor or any other Person all or any
portion of any amount remitted to the L/C Issuer pursuant to this Agreement, the
Lenders shall promptly remit to the L/C Issuer, upon three (3) Business Days'
demand therefor, their respective Ratable Shares of the amount which is so
refunded or repaid.

          (d) In the event any restrictions are imposed upon the L/C Issuer or
any of the Lenders by any Law or any Official Body having jurisdiction over the
banking activities of the L/C Issuer or any Lender which would prevent the L/C
Issuer from issuing the Letters of Credit or amending the Letters of Credit or
would prevent any Lender from honoring its obligations under this Section 2.18,
the commitment of the L/C Issuer to issue the Letters of Credit or enter into
any amendment with respect thereto shall be immediately suspended. If any Lender
believes any such restriction would prevent such Lender from honoring its
obligations under this Section 2.18, it shall promptly notify the Agent. The
Agent shall promptly notify the Borrower, the L/C Issuer and the other Lenders
of the existence and nature of (i) any restriction which would cause the
suspension of the commitment of the L/C Issuer to issue the Letters of Credit or
to enter into amendments with respect thereto and (ii) any restriction which
would prevent any Lender from honoring its obligations under this Section 2.18.
The Borrower will thereupon undertake reasonable efforts to obtain the
cancellation of all outstanding Letters of Credit; provided, however, that
                                                   --------  -------
the refusal of any beneficiary of a Letter of Credit to surrender such Letter of
Credit will not be an Event of Default hereunder, provided that the Borrower
shall undertake good faith efforts to obtain substitute letters of credit for
the then existing and outstanding Letters of Credit. Nothing contained in this
Section 2.18 shall be deemed a termination of the Revolving Credit Commitments
and, in the event of a suspension of the commitment of the L/C Issuer to issue
Letters of Credit as set forth above, the Borrower may continue to borrow under
the Revolving Credit Commitments provided the requirements of Section 5.02 are
complied with.

          (e) When the Borrower desires the issuance of a Letter of Credit, the
Borrower shall deliver a duly completed Application for Letter of Credit to the
L/C Issuer, with a copy to the Agent, no later than 11:00 A.M. (Pittsburgh,
Pennsylvania time) at least three (3) Business Days, or such shorter period as
may be agreed to by the L/C Issuer, in advance of the proposed date of issuance.
Upon satisfaction of the conditions set forth in Section 5.01, if applicable,
and Section 5.02, the L/C Issuer shall be obligated to issue the Letter of
Credit and shall notify the Agent and each Lender of such issuance. In
determining whether to pay under a Letter of Credit, the L/C Issuer shall be
responsible only to determine that the documents and certificates required to be
delivered under the Letter of Credit have been delivered and that they comply on
their face with the requirements of the Letter of Credit.

          (f) In the event of any request for drawing under a Letter of Credit
by the beneficiary thereof, the L/C Issuer shall immediately notify the Borrower
and the Agent, and the Borrower shall reimburse, or cause the reimbursement of,
the L/C Issuer on demand as set
<PAGE>
 
forth in the applicable Application for Letter of Credit in an amount in same
day funds equal to the amount of such drawing; provided, however, that anything
contained in this Agreement to the contrary notwithstanding, unless the Borrower
shall have notified the Agent and the L/C Issuer prior to such time that the
Borrower intends to reimburse the L/C Issuer for all or a portion of the amount
of such drawing with funds other than the proceeds of Loans, the Borrower shall
be deemed to have given a Loan Request to the Agent requesting the Lenders to
make Loans on the first Business Day immediately following the date on which
such drawing is honored in an aggregate amount equal to the excess of the amount
of such drawing over the amount received by the L/C Issuer from such other funds
in reimbursement thereof (the "Unreimbursed L/C Draw"), plus accrued interest on
such amount at the rate set forth in Subsection 2.08. Any such Loan shall be
deemed advanced to the Borrower. If the Borrower shall be deemed to have given a
Loan Request, then, subject to satisfaction or waiver of the conditions
specified in Section 5.02, the Lenders shall, all as set forth in Section
2.18(g) hereof, on the first Business Day immediately following the date of such
drawing, make Loans in the aggregate amount of the Unreimbursed L/C Draw plus
accrued interest on such amount at the applicable rate set forth in Section
2.08. The proceeds of any such Loans shall be applied directly by the Agent upon
receipt from the Lenders to reimburse the L/C Issuer for the Unreimbursed L/C
Draw plus accrued interest on such amount. The foregoing shall not limit or
impair the obligation of the Borrower to reimburse the L/C Issuer on demand.

          (g) In the event that the Borrower shall fail to reimburse the L/C
Issuer on demand as provided in the applicable Application for Letter of Credit
and Section 2.18(f) above in an amount equal to the amount of any drawing
honored by the L/C Issuer under a Letter of Credit plus accrued interest, the
L/C Issuer shall promptly notify the Agent and each Lender of the Unreimbursed
L/C Draw plus accrued interest on such amount of such drawing and of such
Lender's respective participation therein. Each Lender shall make available to
the L/C Issuer an amount equal to its respective participation in same day
funds, at the office of the L/C Issuer specified in such notice, not later than
12:00 Noon (Pittsburgh, Pennsylvania time) on the Business Day after the date
specified in such notice by the L/C Issuer. In the event that any Lender fails
to make available to the L/C Issuer the amount of such Lender's participation in
such Letter of Credit as provided in this Section 2.18(g), the L/C Issuer shall
be entitled to recover such amount on demand from such Lender together with
interest at the Federal Funds Effective Rate for three (3) Business Days and
thereafter at the Base Rate. Nothing in this Section 2.18(g) shall be deemed to
prejudice the right of any Lender to recover its Ratable Share of the
Unreimbursed L/C Draw from the L/C Issuer pursuant to this Section 2.18(g) in
the event that it is determined by a court of competent jurisdiction that
payment with respect to a Letter of Credit by the L/C Issuer constituted gross
negligence or willful misconduct on the part of the L/C Issuer. The L/C Issuer
shall distribute to each Lender which has paid all amounts payable by it under
this Section 2.18(g) with respect to a Letter of Credit such other Lender's
Ratable Share of all payments received by the L/C Issuer from the Borrower in
reimbursement of drawing honored by the L/C Issuer under the Letter of Credit
when such payments are received.

          (h) The obligations of the Borrower under this Agreement to reimburse
the L/C Issuer for all drawings upon the Letters of Credit shall be absolute,
unconditional and irrevocable, and shall not be subject to any right of set-off
or counterclaim and shall be paid or performed strictly in accordance with the
terms of this Agreement, under all circumstances whatsoever, including the
following circumstances:
<PAGE>
 
              (i) any lack of validity or enforceability of this Agreement, any
Letter of Credit or any of the Loan Documents;

              (ii) any amendment or waiver of any provision of all or any of the
Loan Documents;

              (iii) the existence of any claim, set-off, defense or other rights
which the Borrower may have at any time against any beneficiary or any
transferee of any Letter of Credit (or any Persons for whom any such beneficiary
or any such transferee may be acting), the L/C Issuer, the Agent or any Lender
(other than the defense of payment to the L/C Issuer in accordance with the
terms of this Agreement) or any other Person, whether in connection with this
Agreement, the Loan Documents or any transaction contemplated hereby or thereby
or any unrelated transaction;

              (iv) any draft, demand, certificate, statement or document
presented under any Letter of Credit, appearing on its face to be valid and
sufficient, but proving to be forged, fraudulent, invalid or insufficient in any
respect or any statement therein being untrue or inaccurate in any respect
whatsoever;

              (v) payment by the L/C Issuer under any Letter of Credit against
presentation of any document which does not comply with the terms of the Letter
of Credit, provided that such payment shall not have constituted gross
negligence or willful misconduct of the L/C Issuer;

              (vi) any other circumstance or happening whatsoever, whether or
not similar to any of the foregoing, not resulting from gross negligence or
willful misconduct of the L/C Issuer; and

              (vii) the fact that a Default or Event of Default shall have
occurred and be continuing.

          (i) This Agreement is intended to supplement each Application for
Letter of Credit executed by the Borrower and delivered to the L/C Issuer.
Whenever possible this Agreement is to be construed as consistent with each
Application for Letter of Credit but, to the extent that the provisions of this
Agreement and each Application for Letter of Credit conflict, the terms of this
Agreement shall control.

          (j) Obligations Absolute. Notwithstanding any other provision of this
              --------------------  
Agreement, each Lender hereby agrees that its obligation to participate in each
Letter of Credit issued in accordance herewith and its obligation to make the
payments to be made by it under this Section 2.18 is absolute, irrevocable and
unconditional and shall not be affected by any event, condition or circumstance
whatever. The failure of any Lender to make any such payment shall not relieve
any other Lender of its funding obligation hereunder on the date due, but no
Lender shall be responsible for the failure of any other Lender to meet its
funding obligations hereunder.
<PAGE>
 
          (k) In addition to amounts payable as elsewhere provided in this
Section 2.18, the Borrower hereby agrees to protect, indemnify, pay and save the
Agent or the L/C Issuer harmless from and against any and all claims, demands,
liabilities, damages, losses, costs, charges and expenses (including reasonable
attorneys' fees) which the Agent or the L/C Issuer may incur or be subject to as
a consequence, direct or indirect, of (i) the issuance of the Letters of Credit
or any amendment thereto, other than as a result of the gross negligence or
willful misconduct of the Agent or the L/C Issuer as determined by a court of
competent jurisdiction, (ii) the failure of the L/C Issuer to honor a draw under
any Letter of Credit if the L/C Issuer in good faith and upon advice of counsel
believes that it is prohibited from making such payment as a result of any
requirement of Law or of any Official Body, or (iii) any material breach by the
Borrower of any representation, warranty, covenant, term or condition in, or the
occurrence of any default under, any document related to the issuance or any
amendment of the Letters of Credit. If any proceeding shall be brought or
threatened against the Agent or the L/C Issuer by reason of or in connection
with any event described in clauses (i) through (iii) above, the Agent shall
promptly notify the Borrower in writing, and the Borrower shall assume the
defense thereof, including the employment of counsel and payment of all costs of
litigation. Notwithstanding the preceding sentence, the Agent and the L/C Issuer
shall have the right to employ its own counsel and to determine its own defense
of such action in any such case, but the fees and expenses of such counsel shall
be at the expense of the Agent or the L/C Issuer, as the case may be, unless (x)
the employment of such counsel shall have been authorized in writing by the
Borrower, (y) the Borrower, after the aforementioned notice of the action, shall
not have employed counsel to have charge of such defense or (z) if the position
of the Borrower is adverse or contrary to the position advocated by the Agent or
the L/C Issuer, as the case may be. In each case described in clauses (x), (y)
and (z) immediately above the reasonable fees and expenses of counsel for the
Agent or the L/C Issuer, as the case may be shall be borne by the Borrower. The
Borrower shall not be liable for any settlement of any such action affected
without its consent.

          (l) The L/C Issuer is hereby expressly authorized and directed to
honor any request for payment which is made under and in compliance with the
terms of any Letter of Credit without regard to, and without any duty on the L/C
Issuer's part to inquire into, the existence of any disputes or controversies
between the Borrower, the beneficiary of any Letter of Credit or any other
Person, or the respective rights, duties or liabilities of any of them or
whether any facts or occurrences represented in any of the documents presented
under any Letter of Credit are true or correct. Furthermore, the Borrower fully
understands and agrees that the L/C Issuer's sole obligation to the Borrower
shall be limited to honoring requests for payment made under and in compliance
with the terms of any Letter of Credit, the Application for Letter of Credit
therefor and this Agreement and the L/C Issuer's obligation remains so limited
even if the L/C Issuer may have assisted the Borrower in the preparation of the
wording of any Letter of Credit or any documents required to be presented
thereunder or that the L/C Issuer may otherwise be aware of the underlying
transaction giving rise to any Letter of Credit and this Agreement.

          (m) As between the Borrower and the L/C Issuer, the Borrower assumes
all risks of the acts and omissions of, or misuse of the Letters of Credit by,
the beneficiaries of the Letters of Credit. In furtherance and not in limitation
of the foregoing, the L/C Issuer shall not be responsible: (i) for the form,
validity, sufficiency, accuracy, genuineness or legal effect of any document
submitted by any party in connection with the application for or
<PAGE>
 
the issuance or amendment of the Letters of Credit, even if it should in fact
prove to be in any or all respects invalid, insufficient, inaccurate, fraudulent
or forged; (ii) for the validity or sufficiency of any instrument transferring
or assigning or purporting to transfer or assign the Letters of Credit or the
rights or benefits thereunder or proceeds thereof, in whole or in part, which
may prove to be invalid or ineffective for any reason; (iii) for failure of a
beneficiary of a Letter of Credit to comply fully with conditions required in
order to draw upon such Letter of Credit; (iv) for errors, omissions,
interruptions or delays in transmission or delivery of any messages, by mail,
cable, telegraph, telecopy, telex or otherwise, whether or not they be in
cipher; (v) for errors in interpretation of technical terms; (vi) for any loss
or delay in the transmission or otherwise of any document required in order to
make a draw under the Letters of Credit or of the proceeds thereof; (vii) for
the misapplication by a beneficiary of any Letter of Credit of the proceeds of
any drawing under such Letter of Credit; (viii) for any consequences arising
from causes beyond the control of the L/C Issuer, including, without limitation,
any Law; and (ix) for any other circumstances whatsoever in making or failing to
make payment under a Letter of Credit; except that the Borrower shall have a
claim against the L/C Issuer, and the L/C Issuer shall be liable to the
Borrower, to the extent, but only to the extent, of any direct, as opposed to
consequential, damages suffered by the Borrower by a court of competent
jurisdiction to be the result of (i) the L/C Issuer's willful misconduct or
gross negligence in determining whether documents presented under a Letter of
Credit comply with the terms of the Letter of Credit, (ii) the L/C Issuer's
willful misconduct or gross negligence in paying a draw under a Letter of Credit
to any Person other than the beneficiary of such Letter of Credit or its lawful
successor, representative or assign (or as otherwise directed in writing by the
beneficiary of such Letter of Credit) or (iii) the L/C Issuer's willful failure
to pay under a Letter of Credit after the presentation to it by the beneficiary
of such Letter of Credit or its lawful successor, representative or assign of a
sight draft and certificate or other documents strictly complying with the terms
and conditions of such Letter of Credit, unless the L/C Issuer in good faith and
upon advice of counsel believes that it is prohibited by law or other legal
authority from making such payment. None of the above shall affect, impair, or
prevent the vesting of any of the L/C Issuer's rights or powers hereunder.

          (n) Except for the L/C Issuer's obligations to issue Letters of Credit
hereunder and its obligations under such Letters of Credit, the L/C Issuer shall
have no liability to the Borrower from a reduction of the L/C Issuer's credit
rating or any deterioration in its financial condition.

          (o) The Borrower shall bear and pay all reasonable expenses of every
kind (including all reasonable attorneys' fees) of the enforcement of any of the
L/C Issuer's rights under this Agreement or the Letters of Credit, or of any
claim or demand by the L/C Issuer against the Borrower, or of any actual or
attempted sale, exchange, enforcement, collection, maintenance, retention,
insurance, compromise, settlement, release, delivery on trust receipt, or other
security agreement, or delivery of any such security, and of the receipt of
proceeds thereof, and will repay to the L/C Issuer any such expenses incurred by
the L/C Issuer.

          (p) In furtherance and extension and not in limitation of the specific
provisions hereinabove set forth, any action taken or omitted by the L/C Issuer
under or in connection with the Letters of Credit or the related sight drafts or
certificates or documents, if
<PAGE>
 
taken or omitted in good faith, shall not put the L/C Issuer under any resulting
liability to the Borrower.

          (q) Whenever appropriate to prevent unjust enrichment and to the end
that the Borrower shall bear substantially all of the risks relative to any
Letter of Credit and the underlying transactions, the L/C Issuer shall be
subrogated (for purposes of defending against the Borrower's claims and
proceeding against others to the extent of the L/C Issuer's liability to the
Borrower) to the Borrower's rights against any Person who may be liable to the
Borrower on any underlying transaction, to the rights of any holder in due
course or Person with similar status against the Borrower, and to the rights of
the beneficiary or its assignee or person with similar status against the
Borrower.

          (r) Except and to the extent inconsistent with the specific provisions
hereof, this Agreement, each Letter of Credit hereunder and all transactions in
connection therewith shall be interpreted, construed and enforced according to:
(i) the "Uniform Customs and Practice for Documentary Credits" (1993 Revision),
International Chamber of Commerce Publication No. 500 and subsequent revisions
thereof which shall supersede inconsistent provisions of applicable law to the
extent not prohibited by applicable law and (ii) the laws of the Commonwealth of
Pennsylvania, including, without limitation, the Uniform Commercial Code, and
excluding conflict of laws rules.

    2.19.  Taxes.
           -----   

          (a) No Deductions. All payments made by the Borrower hereunder and
              -------------                                                 
under each Note shall be made free and clear of and without deduction for any
present or future taxes, levies, imposts, deductions, charges, or withholdings,
and all liabilities with respect thereto, excluding taxes imposed on the net
income of any Lender and all income and franchise taxes applicable to any Lender
of the United States (all such non-excluded taxes, levies, imposts, deductions,
charges, withholdings, and liabilities being hereinafter referred to as
"Taxes").  If the Borrower shall be required by Law to deduct any Taxes from or
in respect of any sum payable hereunder or under any Note, (i) the sum payable
shall be increased as may be necessary so that after making all required
deductions (including deductions applicable to additional sums payable under
this Section 2.19(a) each Lender receives an amount equal to the sum it would
have received had no such deductions been made, (ii) the Borrower shall make
such deductions and (iii) the Borrower shall timely pay the full amount deducted
to the relevant tax authority or other authority in accordance with applicable
law.

          (b) Stamp Taxes. In addition, the Borrower agrees to pay any present
              -----------                                                     
or future stamp or documentary taxes or any other excise or property taxes,
charges, or similar levies which arise from any payment made hereunder or from
the execution, delivery, or registration of, or otherwise with respect to, this
Agreement or any Note (hereinafter referred to as "Other Taxes").

          (c) Indemnification for Taxes Paid by a Lender. The Borrower shall
              ------------------------------------------                    
indemnify each Lender for the full amount of Taxes or Other Taxes (including
without limitation, any Taxes or Other Taxes imposed by any jurisdiction on
amounts payable under this Section 2.19(c)) paid by any Lender and any liability
(including penalties, interest, and expenses) arising therefrom or with respect
thereto, whether or not such Taxes or Other Taxes were correctly or
<PAGE>
 
legally asserted. This indemnification shall be made within 30 days from the
date a Lender makes written demand therefor.

          (d) Certificate. Within 30 days after the date of any payment of any
              -----------                                                     
Taxes or Other Taxes by the Borrower on behalf of a Lender, the Borrower shall
furnish to each Lender, at its address referred to herein, the original or a
certified copy of a receipt evidencing payment thereof.  If no Taxes are payable
in respect of any payment by the Borrower, the Borrower shall, if so requested
by a Lender, provide a certificate of an officer of the Borrower to that effect.

          (e) Withholding. Each Lender that is not incorporated under the laws
              -----------                                                     
of the United States of America or a state thereof agrees that it will deliver
to the Borrower and the Agent (i) two duly completed copies of United States
Internal Revenue Service Form 1001 or 4224 or successor applicable form, as the
case may be (assuming that it is entitled to do so), and (ii) two duly completed
copies of Internal Revenue Service Form W-8 or W-9 or successor applicable form.
Each such Lender also agrees to deliver to the Borrower and the Agent two
further copies of the said Form 1001 or 4224 and Form W-8 or W-9, or successor
applicable forms or other manner of certification, as the case may be, on or
before the date that any such form expires or becomes obsolete or otherwise is
required to be resubmitted as a condition to obtaining an exemption from
withholding tax or after the occurrence of any event requiring a change in the
most recent form previously delivered by it to the Borrower and the Agent, and
such extensions or renewals thereof as may reasonably be requested by the
Borrower or the Agent, unless in any such case an event (including, without
limitation, any change in treaty, law or regulation) has occurred prior to the
date on which any such delivery would otherwise be required which renders all
such forms inapplicable or which would prevent such Lender from duly completing
and delivering any such form with respect to it and such Lender so advises the
Borrower and the Agent. Such Lender shall certify (i) in the case of Form 1001
or 4224, that it is entitled to receive payments under this Agreement without
deduction or withholding of any United States federal income taxes (assuming
that it is entitled to do so) and (ii) in the case of Form W-8 or W-9, that it
is entitled to an exemption from United States backup withholding tax.

          (f) Survival. Without prejudice to the survival of any other agreement
              --------                                                          
of the Borrowers hereunder, the agreements and obligations of the Borrower
contained in this Section 2.19 shall survive the payment in full of principal
and interest hereunder and under any instrument delivered hereunder.

     2.20. Payments. All payments and prepayments to be made in
           --------                                              
respect of principal, interest, Unreimbursed L/C Draws, Fees, or other amounts
due from the Borrower hereunder (except those Optional Currency payments and
prepayments made pursuant to Section 2.13(f) hereof) shall be payable prior to
11:00 A.M. (Pittsburgh, Pennsylvania time) on the date when due without
presentment, demand, protest or notice of any kind, all of which are hereby
expressly waived by the Borrower, and without setoff, counterclaim or other
deduction of any nature, and an action therefor shall immediately accrue. Such
payments shall be made to the Agent at the Principal Office for the ratable
account of the Lenders or L/C Issuer, as the case may be, in Dollars and in
immediately available funds, and the Agent shall promptly distribute such
amounts to the Lenders or L/C Issuer, as the case may be, in immediately
available funds in accordance with the terms and provisions of Section 9.10 of
this Agreement. The Agent's, the L/C Issuer's and each Lender's statement of
account, ledger or other relevant
<PAGE>
 
record shall, in the absence of manifest error, be conclusive as the statement
of the amount of principal of and interest on the Loans, the Unreimbursed L/C
Draws, Fees and other amounts owing under this Agreement and shall be deemed an
"account stated." Notwithstanding anything herein to the contrary, (i) any
administration or underwriting fee paid by the Borrower to the Agent shall be
solely for the account of the Agent, (ii) any L/C Fronting Fees paid by the
Borrower shall be solely for the account of the L/C Issuer and (iii) any
interest paid on any Unreimbursed L/C Draw to the extent a Lender has not been
required to honor or has not honored its funding obligations pursuant to Section
2.18(g) hereof shall be solely for the account of the L/C Issuer.

          2.21.  Judgment Currency.
                 -----------------   

          (a) Currency Conversion Procedures for Judgments.  If for the purposes
              --------------------------------------------                      
of obtaining judgment in any court it is necessary to convert a sum due
hereunder or under a Note in any currency (the "Original Currency") into another
currency (the "Other Currency"), the parties hereby agree, to the fullest extent
permitted by Law, that the rate of exchange used shall be that at which in
accordance with normal banking procedures each Lender could purchase the
Original Currency with the Other Currency after any premium and costs of
exchange on the Business Day preceding that on which final judgment is given.

          (b) Indemnity in Certain Events.  The obligation of the Borrower in
              ---------------------------                                    
respect of any sum due from the Borrower to any Lender hereunder shall,
notwithstanding any judgment in an Other Currency, whether pursuant to a
judgment or otherwise, be discharged only to the extent that, on the Business
Day following receipt by any Lender of any sum adjudged to be so due in such
Other Currency, such Lender may in accordance with normal banking procedures
purchase the Original Currency with such Other Currency.  If the amount of the
Original Currency so purchased is less than the sum originally due to such
Lender in the Original Currency, the Borrower agrees, as a separate obligation
and notwithstanding any such judgment or payment, to indemnify such Lender
against such loss.

                                  ARTICLE III
                  LOAN DISBURSEMENT ACCOUNT, GUARANTEES, ETC.
                  ------------------------------------------ 

          3.01. Loan Disbursement Account. The Borrower shall maintain at all
                -------------------------
times during this Agreement with the Agent, at the Agent's office in Pittsburgh,
Pennsylvania, a demand deposit account (the "Loan Disbursement Account"), into
which proceeds of Loans and other monies transferred to the Borrower hereunder
shall be deposited from time to time. The Loan Disbursement Account shall be in
the name of the Borrower and, subject to the other provisions of this Agreement
and the other Loan Documents, monies therein shall be disbursed as directed by
the Borrower, from time to time. To secure the payment and performance of Lender
Obligations, the Borrower hereby pledges and assigns, and grants to the Agent
for the benefit of the Agent, the L/C Issuer and the Lenders, a lien on and
security interest in the Loan Disbursement Account, all funds from time to time
deposited or held therein, all interest and other income derived therefrom, and
all proceeds of all the foregoing.

          3.02. Designation of Subsidiary Guarantors. Each Subsidiary of the
                ------------------------------------
Borrower incorporated or organized in the United States of America or in a state
thereof, whether now in existence or hereafter acquired shall be automatically
designated as a Subsidiary Guarantor by
<PAGE>
 
the Lenders. Any Subsidiary designated as a Subsidiary Guarantor shall continue
as a Subsidiary Guarantor until released in writing by all of the Lenders.

          3.03.  Foreign Subsidiaries.    The Borrower shall, and shall cause
                 --------------------                                        
each of its domestic Subsidiaries, to pledge to the Agent for the benefit of the
Lenders 65% of its ownership interest in each Subsidiary not incorporated or
organized in the United States of America or a state thereof.

          3.04. Further Cooperation. The Borrower shall perform, or cause each
                -------------------
other Loan Party to perform, on the reasonable request of the Agent and at the
Borrower's expense, such reasonable acts as may be necessary or reasonably
advisable to carry out the intent of this Agreement and the other Loan
Documents. Without limiting the generality of the preceding sentence, the
Borrower shall cause each newly-created or acquired Subsidiary Guarantor to
execute and deliver a Subsidiary Guaranty to the Agent with a reasonable period
of time following the creation or acquisition of such Subsidiary Guarantor and
shall execute and deliver or cause the relevant Loan Party to execute and
deliver a Pledge Agreement relating to the equity interest in any hereafter
acquired or created foreign Subsidiary.

                                   ARTICLE IV
                         REPRESENTATIONS AND WARRANTIES
                         ------------------------------

  Representations and Warranties. The Borrower represents and warrants to the
  ------------------------------                                             
Agent, each of the Lenders and the L/C Issuer as follows:

          4.01.  Organization and Qualification.
                 ------------------------------   

                 (a) The Borrower is a corporation duly organized, validly
existing and in good standing under the laws of the Commonwealth of
Pennsylvania, the Borrower has the lawful power to own or lease its properties
and to engage in the business it presently conducts or proposes to conduct; and
the Borrower is duly licensed or qualified and in good standing in each
jurisdiction listed on Schedule 4.01 hereto and in all other jurisdictions where
                       -------------
the property owned or leased by it or the nature of the business transacted by
it makes such licensing or qualification necessary, except for those
jurisdictions where the Borrower's non-qualification would not cause there to be
a Material Adverse Change.

                 (b) Each Subsidiary of the Borrower is a corporation, business
trust, limited liability company or limited partnership, as the case may be,
duly organized, validly existing and in good standing under the laws of the
jurisdiction of its incorporation or organization, as the case may be, shown on
Schedule 4.01; each Subsidiary of the Borrower has the lawful power to own or
-------------
lease its properties and to engage in the business it presently conducts or
proposes to conduct; and each Subsidiary of the Borrower is duly licensed or
qualified and in good standing in each jurisdiction listed on Schedule 4.01
                                                              -------------
hereto and in all other jurisdictions where the property owned or leased by it
or the nature of the business transacted by it makes such licensing or
qualification necessary, except for those jurisdictions where such Subsidiary's
non-qualification would not cause there to be a Material Adverse Change.

          4.02. Capitalization and Ownership. As of September 30, 1998, the
                ----------------------------
authorized capital stock of the Borrower consists of 200,000,000 shares of
common stock of which
<PAGE>
 
49,041,861 shares were issued and outstanding, and 20,000,000 shares of
preferred stock, of which one (1) share is issued and outstanding. All of the
capital stock of the Borrower has been validly issued and is fully paid and non-
assessable. Except as set forth in Schedule 4.02, there are no options, warrants
                                   -------------
or other rights outstanding to purchase any such capital stock.

          4.03. Subsidiaries. Except for the Subsidiaries and investments in
                ------------
other Persons set forth in Schedule 4.03, the Borrower does not own directly or
                           ------------- 
indirectly any capital stock of any other Person, is not a partner (general or
limited) of any partnership, is not a party to any joint venture and does not
own (beneficially or of record) any equity interest or similar interest in any
other Person.

          4.04. Power and Authority. The Borrower and each other Loan
                -------------------                                    
Party has full power to enter into, execute, deliver, carry out and perform this
Agreement and the Loan Documents to which it is a party, to incur the
Indebtedness contemplated by the Loan Documents and to perform its obligations
under the Loan Documents to which it is a party and all such actions have been
duly authorized by all necessary corporate proceedings on its part.

          4.05. Validity and Binding Effect. This Agreement has been,
                ---------------------------                            
and each Loan Document, when executed and delivered by the Borrower and each
other Loan Party, will have been, duly and validly executed and delivered by the
Borrower or such Loan Party.  This Agreement and each of the other Loan
Documents executed and delivered by the Borrower and each Loan Party will
constitute legal, valid and binding obligations of the Borrower or such Loan
Party, enforceable against the Borrower or such Loan Party in accordance with
their respective terms, except to the extent that enforceability of any of the
Loan Documents may be limited by bankruptcy, insolvency, reorganization,
moratorium or other similar laws affecting the enforceability of creditors'
rights generally or limiting the right of specific performance.

          4.06. No Conflict.
                -----------   

                (a) Neither the execution and delivery by the Borrower of this
Agreement or the Loan Documents to which the Borrower is a party, nor the
consummation of the transactions herein or therein contemplated, nor compliance
with the terms and provisions hereof or thereof by the Borrower will (i)
conflict with, constitute a default under or result in any breach of (A) the
terms and conditions of the articles of incorporation, by-laws or other
organizational documents of the Borrower or (B) any Law or any agreement or
instrument or order, writ, judgment, injunction or decree to which the Borrower
is a party or by which it is bound or to which it is subject, which conflict,
default or breach would cause a Material Adverse Change, or (ii) result in the
creation or enforcement of any Lien upon any property (now or hereafter
acquired) of the Borrower (other than the Permitted Liens).

                (b) Neither the execution and delivery by a Loan Party of a
Subsidiary Guaranty or Pledge Agreement to which such Loan Party is a party, nor
the consummation of the transactions contemplated by this Agreement or the other
Loan Documents, nor compliance with the terms and provisions hereof or thereof
by such Loan Party will (i) conflict with, constitute a default under or result
in any breach of (A) the terms and conditions of the articles of incorporation,
by-laws or other organizational documents of such Subsidiary or (B) any Law or
any agreement or instrument or order, writ, judgment, injunction or decree to
which such Loan Party is a party or by which it is bound or to which it is
subject, which conflict, default or
<PAGE>
 
breach would cause a Material Adverse Change, or (ii) result in the creation or
enforcement of any Lien upon any property (now or hereafter acquired) of such
Loan Party (other than the Permitted Liens).

          4.07. Litigation. Except for the litigation set forth on Schedule
                ----------                                         --------
4.07, there are no actions, suits, proceedings or investigations pending or, to
----
the knowledge of the Borrower, threatened against the Borrower or any Subsidiary
of the Borrower, at law or in equity, before any Official Body which
individually or in the aggregate, if adversely determined, would be likely to
result in any Material Adverse Change. Neither the Borrower nor any Subsidiary
of the Borrower is in violation of any order, writ, injunction or decree of any
Official Body which could be expected to result in any Material Adverse Change.

          4.08. Financial Statements.
                --------------------   

                (a) Financial Statements. The Borrower has delivered to the
                    --------------------
Agent the consolidated annual financial statements of the Borrower and its
Subsidiaries for the Fiscal Year ended December 31, 1997, and the consolidated
quarterly financial statements of the Borrower and its Subsidiaries for the
Fiscal Quarter ended September 30, 1998. All such financial statements are
complete and correct in all material respects and fairly present the
consolidated financial condition of the Borrower and its Subsidiaries in all
material respects and the results of their operations as of the dates and for
the periods referred to, and have been prepared in accordance with GAAP
throughout the period included.

                (b) Accuracy of Financial Statements. The Borrower and its
                    --------------------------------   
Subsidiaries have no material liabilities, contingent or otherwise, that are not
disclosed in the financial statements referred to in clause (a) above and that
would be required to be disclosed in accordance with GAAP, except for those
incurred since the date of such financial statements in the ordinary course of
business and, in the case of quarterly financial statements, subject to year end
audit adjustments.


          4.09. Margin Stock; Section 20 Subsidiaries. Neither the Borrower nor
                -------------------------------------
any of its Subsidiaries engage or intend to engage principally, or as one of its
important activities, in the business of incurring Indebtedness or extending
credit to others (including, without limitation, any of the Subsidiaries of the
Borrower) for the purpose, immediately, incidentally or ultimately, of
purchasing or carrying margin stock (within the meaning of any Margin
Regulation). No part of the proceeds of any Loan has been or will be used,
immediately, incidentally or ultimately, to purchase or carry any margin stock
or to extend credit to others (including, without limitation, any of its
Subsidiaries) for the purpose of purchasing or carrying any margin stock or to
refund or retire Indebtedness originally incurred for such purpose, or for any
purpose which entails a violation of or which is inconsistent with the
provisions of the Margin Regulations. The Borrower does not intend to hold, and
shall not permit its Subsidiaries to hold, margin stock. Neither the Borrower
not any of its Subsidiaries intends to use any portion of the proceeds of the
Loans, directly or indirectly, to purchase during the underwriting period, or
for thirty (30) days thereafter, Ineligible Securities being underwritten by a
Section 20 Subsidiary.

          4.10. Full Disclosure. Neither this Agreement nor any Loan
                ---------------                                       
Document, nor any certificate, statement, agreement or other document furnished
to the Agent, the L/C Issuer or
<PAGE>
 
any Lender in connection herewith or therewith, contains any misstatement of a
material fact or omits to state a material fact necessary in order to make the
statements contained herein and therein, in light of the circumstances under
which they were made, not misleading. There is no fact known to the Borrower
which materially adversely affects the business, property, assets, financial
condition, results of operations or prospects of the Borrower and its
Subsidiaries, taken as a whole, which has not been set forth in this Agreement
or the Loan Documents or in the certificates, statements, agreements or other
documents furnished in writing to the Agent, the Lenders or the L/C Issuer prior
to or at the date hereof in connection with the transactions contemplated hereby
and thereby.

          4.11. Tax Returns and Payments. The Borrower is a member of
                ------------------------                               
an affiliated group of companies which files consolidated federal tax returns.
All such federal tax returns that are required by law to be filed have been
filed or properly extended. All taxes, assessments and other governmental
charges levied upon members of such affiliated group or any of their respective
properties, assets, income or franchises which are due and payable have been
paid in full other than (i) those presently payable without penalty or interest,
(ii) those which are being contested in good faith by appropriate proceedings
and (iii) those which, if not paid, would not, in the aggregate, constitute a
Material Adverse Change; and as to each of items (i), (ii) and (iii) the
affiliated group has established reserves for such claim as have been determined
to be adequate by application of GAAP consistently applied. There are no
agreements or waivers extending the statutory period of limitations applicable
to any consolidated federal income tax return of the Borrower and its
consolidated Subsidiaries for any period, except as set forth on Schedule 4.11.
                                                                 ------------- 

          4.12. Consents and Approvals. No consent, approval, exemption, order
                ----------------------
or authorization of, or a registration or filing with any Official Body or any
other Person is required by any Law or any agreement in connection with the
execution, delivery and carrying out of this Agreement and the Loan Documents to
which the Borrower or any Loan Party is a party, except as listed on Schedule
                                                                     --------
4.12 attached hereto, all of which items set forth on Schedule 4.12 shall have
----                                                  -------------
been obtained or made on or prior to the Closing Date.

          4.13. No Event of Default; Compliance with Instruments. No
                ------------------------------------------------      
event has occurred and is continuing and no condition exists or will exist after
giving effect to the borrowings to be made on the Closing Date under the Loan
Documents which constitutes an Event of Default or a Default. Neither the
Borrower nor any of its Subsidiaries is in violation of (i) any term of its
certificate of incorporation, by-laws or other organizational documents or (ii)
any material agreement or instrument to which it is a party or by which it or
any of its properties may be subject or bound where such violation would
constitute a Material Adverse Change.

          4.14. Compliance with Laws. The Borrower and its Subsidiaries are in
                --------------------
compliance in all material respects with all applicable Laws (other than
Environmental Laws, which are addressed in Section 4.20) in all jurisdictions in
which the Borrower, and its Subsidiaries, are presently or will be doing
business except where the failure to do so would not, individually or in the
aggregate, constitute a Material Adverse Change.

          4.15. Investment Company; Public Utility Holding Company. Neither the
                -------------------------------------------------- 
Borrower nor any Loan Party is an "investment company" registered or required to
be registered under the Investment Company Act of 1940 or under the "control" of
an "investment
<PAGE>
 
company" as such terms are defined in the Investment Company Act of 1940, as
amended from time to time, and shall not become such an "investment company" or
under such "control. " Neither the Borrower nor any Loan Party is a "holding
company" or a "subsidiary company" of a "holding company" or an "affiliate" of a
"holding company" within the meaning the Public Utility Holding Company Act of
1935, as amended from time to time. The Borrower is not subject to any Law of
any Official Body (in each case whether United States federal, state or local,
or other) having jurisdiction over the Borrower, which purports to restrict or
regulate its ability to borrow money, or to extend or obtain credit, or to
pledge its interests in the Loan Disbursement Account. No other Loan Party is
subject to any Law of any Official Body (in each case whether United States
federal, state or local, or other) having jurisdiction over such Loan Party
which purports to restrict or regulate its ability to borrow money or to extend
or obtain credit.

          4.16. Plans and Benefit Arrangements. Except as set forth on Schedule
                ------------------------------                         --------
4.16 hereto:
----

                (a) The Borrower and each member of the ERISA Group are in
compliance in all material respects with any applicable provisions of ERISA with
respect to all Benefit Arrangements, Plans and Multiemployer Plans. There has
been no Prohibited Transaction with respect to any Benefit Arrangement or any
Plan (other than a Multiemployer Plan) or, to the knowledge of the Borrower,
with respect to any Multiemployer Plan or Multiple Employer Plan, which could
result in any material liability of the Borrower or any other member of the
ERISA Group. The Borrower and all members of the ERISA Group have made when due
any and all payments required to be made under any agreement relating to a
Multiemployer Plan or a Multiple Employer Plan or any Law pertaining thereto.
With respect to each Plan and, to the knowledge of Borrower, each Multiemployer
Plan, the Borrower and each member of the ERISA Group (i) have fulfilled in all
material respects their obligations under the minimum funding standards of
ERISA, (ii) have not incurred any liability to the PBGC (other than for premiums
not yet due) and (iii) have not had asserted against them any penalty for
failure to fulfill the minimum funding requirements of ERISA.

                (b) To the best of the Borrower's knowledge, each Multiemployer
Plan and Multiple Employer Plan is able to pay benefits thereunder when due.

                (c) Neither the Borrower nor any other member of the ERISA Group
has instituted or intends to institute proceedings to terminate any Plan.

                (d) No event requiring notice to the PBGC under Section
302(f)(4)(A) of ERISA has occurred or is reasonably expected to occur with
respect to any Plan, and no amendment with respect to which security is required
under Section 307 of ERISA has been made or is reasonably expected to be made to
any Plan.

                (e) Neither the Borrower nor any other member of the ERISA Group
has incurred or reasonably expects to incur any material withdrawal liability
under ERISA to any Multiemployer Plan or Multiple Employer Plan. Neither the
Borrower nor any other member of the ERISA Group has been notified by any
Multiemployer Plan or Multiple Employer Plan that such Multiemployer Plan or
Multiple Employer Plan has been terminated within the meaning of Title IV of
ERISA and, to the knowledge of the Borrower, no Multiemployer Plan or Multiple
<PAGE>
 
Employer Plan is reasonably expected to be reorganized or terminated, within the
meaning of Title IV of ERISA.

                (f) To the extent that any Benefit Arrangement is insured, the
Borrower and all members of the ERISA Group have paid when due all premiums
required to be paid for all periods ending through and including the Closing
Date. To the extent that any Benefit Arrangement is funded other than with
insurance, the Borrower and all members of the ERISA Group have made when due
all contributions, to the extent required by applicable Law or the terms of such
Benefit Arrangement to be paid for all periods ending through and including the
Closing Date.

          4.17. Title to Properties. The Borrower and each of its Subsidiaries
                -------------------
have good title to, or a valid leasehold interest in, all their respective real
and personal property, except to the extent the failure to have such title or
leasehold interests is not reasonably likely, individually or in the aggregate,
to result in a Material Adverse Change, and none of such property is subject to
any Lien except Permitted Liens.

          4.18. Insurance. There are in full force and effect for the benefit of
                ---------
the Borrower and its Subsidiaries insurance policies and bonds providing
adequate coverage from reputable and financially sound insurers in amounts
sufficient to insure the assets and risks of the Borrower and its Subsidiaries
in accordance with prudent business practice in the industry of the Borrower and
its Subsidiaries. No notice has been given or claim made and to the knowledge of
the Borrower, no grounds exist, to cancel or void any of such policies or bonds
or to reduce the coverage provided thereby.

          4.19. Employment Matters. The Borrower and each Subsidiary of the
                ------------------
Borrower are in compliance with all employee benefit plans, employment
agreements, collective bargaining agreements and labor contracts (the "Labor
Contracts") and all applicable federal, state and local labor and employment
Laws including, but not limited to, those related to equal employment
opportunity and affirmative action, labor relations, minimum wage, overtime,
child labor, medical insurance continuation, worker adjustment and relocation
notices, immigration controls and worker and unemployment compensation, except
where the failure to comply would not constitute a Material Adverse Change.
There are no outstanding grievances, arbitration awards or appeals therefrom
arising out of the Labor Contracts or current or, to the knowledge of the
Borrower, threatened strikes, picketing, handbilling or other work stoppages or
slowdowns at facilities of the Borrower or any Subsidiary of the Borrower which
in any case would constitute a Material Adverse Change. All payments due from
Borrower or any of its Subsidiaries on account of employee health and welfare
insurance which could reasonably be expected to have a Material Adverse Change
if not paid have been paid or accrued as a liability on the books of Borrower or
such Subsidiary.

          4.20.  Environmental Matters. Except as disclosed on Schedule
                 ---------------------                         --------
4.20 hereto:
----        

                 (a) The Borrower has not received any Environmental Complaint
from any Official Body or private Person alleging that the Borrower, any
Subsidiary of the Borrower or any prior or subsequent owner of any of the
Property is a potentially responsible party under the Comprehensive
Environmental Response, Cleanup and Liability Act, 42 U.S.C. (S)9601, et seq.,
in connection with the Property which Environmental Complaint is reasonably
expected to
<PAGE>
 
result in any Material Adverse Change, and the Borrower has no reason to believe
that such an Environmental Complaint is reasonably likely to be received. There
are no pending or, to the knowledge of the Borrower, threatened Environmental
Complaints relating to the Borrower, any Subsidiary of the Borrower or, to the
Borrower's knowledge, without any inquiry, any prior or subsequent owner of the
Property pertaining to, or arising out of, any Environmental Conditions in
connection with the Property, which Environmental Complaints are reasonably
expected to result in any Material Adverse Change.

                (b) Except for conditions, violations or failures which
individually and in the aggregate are not reasonably likely to result in a
Material Adverse Change, there are no circumstances at, on or under the Property
that constitute a breach of or non-compliance with any of the Environmental
Laws, and there are no past or present Environmental Conditions at, on or under
the Property or, to the knowledge of the Borrower, without any inquiry at, on or
under adjacent property, that prevent compliance with the Environmental Laws at
the Property.

                (c) Neither the Property nor any structures, improvements,
equipment, fixtures, activities or facilities thereon or thereunder contain or
use Regulated Substances except in compliance with Environmental Laws, other
than such containment or use which individually and in the aggregate is not
reasonably likely to result in any Material Adverse Change. There are no
processes, facilities, operations, equipment or any other activities at, on or
under the Property, or, to the Borrower's knowledge, without any inquiry, at, on
or under adjacent property, that currently result in the release or threatened
release of Regulated Substances on to the Property in violation of the
Environmental Laws, except to the extent that such releases or threatened
releases are not likely to result in a Material Adverse Change.

                (d) There are no underground storage tanks, or underground
piping associated with such tanks, used for the management of Regulated
Substances at, on or under the Property that are not in compliance with all
Environmental Laws, other than those with respect to which the failure to comply
with Environmental Laws is not reasonably likely, either individually or in the
aggregate, to result in a Material Adverse Change, and there are no abandoned
underground storage tanks or underground piping associated with such tanks,
previously used for the management of Regulated Substances at, on or under the
Property that have not been either abandoned in place, or removed, in accordance
with the Environmental Laws, other than those with respect to which the failure
to comply with Environmental Laws is not reasonably likely, either individually
or in the aggregate, to result in a Material Adverse Change.

                (e) The Borrower and each Subsidiary of the Borrower have all
material permits, licenses, authorizations and approvals necessary under the
Environmental Laws for the conduct of the respective businesses of the Borrower
and each Subsidiary of the Borrower as presently conducted, other than those
with respect to which the failure to comply with Environmental Laws is not
reasonably likely, either individually or in the aggregate, to result in a
Material Adverse Change. The Borrower and each Subsidiary of the Borrower have
submitted all notices, reports and other filings required by the Environmental
Laws to be submitted to an Official Body which pertain to past and current
operations on the Property, except for any failure to submit which would not be
reasonably likely to result in a Material Adverse Change.
<PAGE>
 
                (f) Except for violations which individually and in the
aggregate are not likely to result in a Material Adverse Change during the
Borrower's and each Loan Party's ownership or lease of the Property, all past
and present on-site generation, storage, processing, treatment, recycling,
reclamation or disposal of Solid Waste at, on, or under the Property and all
off-site transportation, storage, processing, treatment, recycling, reclamation
or disposal of Solid Waste has been done in accordance with the Environmental
Laws.

          4.21. Senior Debt Status. The obligations of the Borrower
                ------------------                                   
under this Agreement and the Notes rank at least pari passu in priority of
                                                 ---- -----               
payment with all other Indebtedness of the Borrower, except Indebtedness of the
Borrower to the extent secured by Permitted Liens. The obligations of a
Subsidiary Guarantor under a Subsidiary Guaranty executed by such Subsidiary
Guarantor rank at least pari passu in priority of payment with all other
                        ---- -----                                      
Indebtedness of such Subsidiary Guarantor except Indebtedness of such Subsidiary
Guarantor to the extent secured by Permitted Liens. There is no Lien upon or
with respect to any of the properties or income of the Borrower or any of its
Subsidiaries which secures Indebtedness or other obligations of any Person
except for Permitted Liens.

          4.22. Solvency.   On the date hereof, and as of the date of
                --------                                             
each advance of the  Loan and issuance or renewal of any Letter of Credit, as
the case may be, and after giving effect to such advance or the issuance or
renewal of a Letter of Credit, each of the Borrower and each Loan Party is, and
will be, Solvent.

          4.23. Material Contracts; Burdensome Restrictions.   All
                -------------------------------------------       
material contracts relating to the business operations of each Loan Party,
including all employee benefit plans and Labor Contracts, are valid, binding and
enforceable upon such Loan Party and each of the other parties thereto in
accordance with their respective terms, and there is no material default
thereunder with respect to such Loan Party, and there is no material default
thereunder, to the Loan Parties' knowledge, with respect to parties other than
such Loan Party. No contract, lease, agreement or other instrument to which
Borrower or any of its Subsidiaries is a party or is bound and no provision of
any applicable Law or governmental regulation would reasonably be expected to
have a Material Adverse Change.

          4.24 Patents, Trademarks, Copyrights, Licenses, Etc.   The
               -----------------------------------------------      
Borrower and each of its Subsidiaries owns or possesses all the material
patents, trademarks, service marks, trade names, copyrights, licenses,
registrations, franchises, permits and rights necessary to own and operate its
properties and to carry on its business as presently conducted and planned to be
conducted by the Borrower or such Subsidiary, without known possible, alleged or
actual conflict with the rights of others.

          4.25 Year 2000 Problem. The Borrower and its Subsidiaries
               -----------------                                     
have reviewed areas within their business and operations which could be
adversely affected by, and have developed or are developing a program to address
on a timely basis, the risk that certain computer applications used by the
Borrower or its Subsidiaries (or any of their respective material suppliers,
customers or vendors) may be unable to recognize and perform properly date-
sensitive functions involving dates prior to and after December 31, 1999 (the
"Year 2000 Problem"). The Year 2000 Problem will not result in any Material
Adverse Change.
<PAGE>
 
          4.26. Brokers. No broker or finder acting on behalf of Borrower
                ------- 
brought about the obtaining, making or closing of the loans made pursuant to
this Agreement, and Borrower has no obligation to any other Person in respect of
any finder's or brokerage fees in connection with the loans contemplated by this
Agreement.

          4.27. No Material Adverse Change.  No event has occurred since
                --------------------------
September 30, 1998, and is continuing which has had or would reasonably be
expected to have a Material Adverse Change.

                                   ARTICLE V
             CONDITIONS OF LENDING OR ISSUANCE OF LETTER OF CREDIT
             -----------------------------------------------------

  The obligation of each Lender to make the Loans hereunder, or of the L/C
Issuer to issue Letters of Credit hereunder is subject to the performance by the
Borrower of its obligations to be performed hereunder at or prior to the making
of any such Loans or the issuance of any such Letter of Credit, as the case may
be, and to the satisfaction of the following further conditions.

          5.01. Conditions to Initial Borrowings.  On the Closing Date
                --------------------------------                        
the following actions shall be completed or satisfied to the sole satisfaction
of the Agent:

                (a) The representations and warranties of the Borrower or the
other Loan Parties contained in Article IV and in the other Loan Documents
executed and delivered by the Borrower or any of the other Loan Parties in
connection with the Closing shall be true and accurate in all material respects
on and as of the Closing Date with the same effect as though such
representations and warranties had been made on and as of such date (except
representations and warranties which relate solely to an earlier date or time,
which representations and warranties shall be true and correct on and as of the
specific date or times referred to therein), and the Borrower, and each other
Loan Party, shall have performed, observed and complied with all covenants and
conditions hereof and contained in the other Loan Documents; no Event of Default
or Default under this Agreement shall have occurred and be continuing or shall
exist; no Material Adverse Change shall have occurred; and there shall be
delivered to the Agent, for the benefit of each Lender, the L/C Issuer and the
Agent, a certificate of the Borrower, dated the Closing Date and signed by the
Chief Executive Officer, President, Chief Financial Officer or Vice President
Finance of the Borrower, to each such effect.

                (b) There shall be delivered to the Agent for the benefit of
each Lender and the L/C Issuer a certificate dated the Closing Date and signed
by the secretary or an assistant secretary of the Borrower, certifying as
appropriate as to:

                    (i) all corporate action taken by the Borrower in connection
with this Agreement and the other Loan Documents;

                    (ii) the names, offices and titles of the Borrower's officer
or officers authorized to sign this Agreement and the other Loan Documents and
the true signatures of such officer or officers and the identities of the
Authorized Officers permitted to act on behalf of the Borrower for purposes of
this Agreement and the other Loan Documents
<PAGE>
 
and the true signatures of such officers, on which the Agent, each Lender and
the L/C Issuer may conclusively rely;

                    (iii) (A) copies of the Borrower's organizational documents,
including its articles of incorporation as in effect on the Closing Date
certified by the Secretary of the Commonwealth of Pennsylvania as well as a copy
of the Borrower's by-laws and (B) a certificate as to the continued existence
and good standing of the Borrower issued by the Secretary of the Commonwealth of
Pennsylvania;

                    (iv) all corporate or partnership action taken by each other
Loan Party in connection with each Subsidiary Guaranty or Pledge Agreement
executed by such Loan Party ;

                    (v) the names, offices and titles of each Loan Party's
officer or officers authorized to sign each Subsidiary Guaranty or Pledge
Agreement and the true signatures of such officer or officers and the identities
of the Authorized Officers permitted to act on behalf of each Loan Party for
purposes of each Subsidiary Guaranty or Pledge Agreement and the true signatures
of such officers, on which the Agent, each Lender and the L/C Issuer may
conclusively rely; and

                    (vi) (A) copies of each Loan Party's organizational
documents, as in effect on the Closing Date, certified, by the Secretary of
State of the state of its organization and (B) a certificate as to the continued
existence and good standing of each Loan Party issued by the Secretary of State
of the state of its organization.

          (c) This Agreement and the other Loan Documents required by the Agent
to be executed and delivered by the Borrower or another Loan Party at the
Closing shall have been duly executed and delivered by the Borrower to the Agent
for the benefit of the Lenders, the L/C Issuer and the Agent.

          (d) There shall be delivered to the Agent for the benefit of each
Lender a written opinion of Buchanan Ingersoll Professional Corporation for the
Borrower and the other Loan Parties, dated the Closing Date and in form and
substance reasonably satisfactory to the Agent and its counsel as to the matters
set forth on Exhibit "F".
             ----------- 

          (e) All legal details and proceedings in connection with the
transactions contemplated by this Agreement and the other Loan Documents shall
be in form and substance satisfactory to the Agent and its counsel, and the
Agent shall have received all such other counterpart originals or certified or
other copies of such documents and proceedings in connection with such
transactions, in form and substance reasonably satisfactory to the Agent and
said counsel, as the Agent or said counsel may reasonably request.

          (f) No Material Adverse Change shall have occurred since September 30,
1998, and no material litigation shall have been instituted by or against the
Borrower or any Subsidiary or any of their respective material properties or
assets; and there shall be delivered to the Agent for the benefit of each
Lender, the L/C Issuer and the Agent a certificate of the Borrower dated the
Closing Date and signed by the Chief Executive Officer,
<PAGE>
 
President, Chief Financial Officer or Vice President Finance of the Borrower to
each such effect.

          (g) The Borrower shall deliver evidence acceptable to the Agent that
adequate insurance in compliance with Section 6.05 hereof is in full force and
effect.

          (h) All material consents required to effectuate the transactions
contemplated hereby as set forth on Schedule 4.12 shall have been obtained.
                                    -------------

          (i) The making and/or assumption of any Loan or the issuance of a
Letter of Credit or assumption of any reimbursement liability with regard
thereto, shall not contravene any Law applicable to the Borrower, any other Loan
Party, the Agent, the Lenders or the L/C Issuer.

          (j) Except as set forth on Schedule 4.07, no action, suit, proceeding,
                                     -------------
investigation, regulation or legislation shall have been instituted, threatened
or proposed before any court or other Official Body (i) with respect to the
Borrower or its Subsidiaries or this Agreement, the other Loan Documents or the
consummation of the transactions contemplated hereby or thereby to enjoin,
restrain or prohibit, or to obtain damages in respect of, their performance
under this Agreement or any other Loan Documents or the consummation of the
transactions contemplated hereby or thereby or (ii) which in the reasonable
opinion of Agent would have a Material Adverse Change.

          (k) The Agent on its own behalf and on behalf of the Lenders and the
L/C Issuer shall be in receipt of all Fees due and payable on or prior to the
Closing Date and all reimbursable expenses incurred on or prior to the Closing
Date.

          (l) The Credit Agreement dated May 30, 1997, as amended, by and among
Mastech Systems Corporation, the lenders party thereto and PNC Bank, National
Association as agent, shall be terminated and all amounts due thereunder shall
have been paid in full.

          (m) All matters and circumstances set forth as qualifications,
limitations, exceptions, additional matters or other materials set forth in the
Schedules hereto provided by or on behalf of the Borrower or its Subsidiaries
shall be acceptable to the Agent, the L/C Issuer and the Lenders in their
reasonable discretion.

        5.02. Each Additional Loan or Issuance of a Letter of Credit. At the
              ------------------------------------------------------
time of making any Loans or the issuance of, or renewal of, a Letter of Credit
and after giving effect to the proposed borrowings or issuance:

              (a) the representations and warranties of the Borrower contained
in Article IV hereof and in the other Loan Documents shall be true and correct
in all material respects on and as of the earlier of: (x) the date of such
additional Loan or issuance of a Letter of Credit or (y) the specific dates or
times referred to therein, with the same effect as though such representations
and warranties have been made on and as of such date;
<PAGE>
 
              (b) the Borrower shall have performed and complied in all material
respects with all covenants and conditions hereof;

              (c) no Default or Event of Default shall have occurred and be
continuing or shall exist;

              (d) no Material Adverse Change shall have occurred;

              (e) the making of any Loan or the issuance of any Letter of Credit
shall not contravene any Law applicable to the Borrower, any of the Lenders or
the L/C Issuer;

              (f) the Borrower shall have delivered to the Agent, as regards a
Loan, a duly executed and completed Loan Request and with respect to the
issuance of a Letter of Credit, the Borrower shall have delivered a duly
executed Application for Letter of Credit therefor and otherwise complied with
the reasonable requirements of the L/C Issuer not inconsistent with the terms
hereof; and

              (g) Total Utilization shall not exceed the aggregate Revolving
Credit Commitments; provided, however, that prior to the advance of any Loan on
                    --------  -------
a Borrowing Date the proceeds of which will repay any Unreimbursed L/C Draw, for
the purpose of calculating Total Utilization and compliance with this Subsection
5.02(f) on such date, the existing Total Utilization immediately prior to such
advance shall be reduced pro tanto by the dollar amount of the Loans to
                         ---------
be advanced on such Borrowing Date which will be used to repay any outstanding
Unreimbursed L/C Draws.

        5.03. Location of Closing. The Closing shall take place at
              -------------------                                   
10:00 A.M., Pittsburgh, Pennsylvania time, on the Closing Date at the offices of
Tucker Arensberg, P.C., 1500 One PPG Place, Pittsburgh, Pennsylvania 15222, or
at such other time and place as the parties agree.

                                   ARTICLE VI
                             AFFIRMATIVE COVENANTS
                             ---------------------

        The Borrower covenants and agrees that, until payment in full of the
Loans and interest thereon, payment in full of all Letter of Credit
reimbursement obligations and interest thereon, satisfaction of all of the
Borrower's other obligations hereunder and termination of the Revolving Credit
Commitments, and the expiration and cancellation of all Letters of Credit issued
hereunder, the Borrower shall comply, or cause compliance, at all times with the
affirmative covenants set forth in Sections 6.01 through and including Section
6.14.

        6.01. Preservation of Existence, Etc.
              -------------------------------

              (a) The Borrower shall maintain its corporate existence and its
license or qualification and its good standing in the state of its incorporation
and in each other jurisdiction in which its ownership or lease of property or
the nature of its businesses makes such license or qualification necessary
(except for such other jurisdictions in which such failure to be so licensed or
qualified individually and in the aggregate would not result in a Material
Adverse Change).
<PAGE>
 
              (b) Each Subsidiary of the Borrower shall maintain its corporate
existence and its license or qualification and its good standing in the
jurisdiction of its incorporation and in each other jurisdiction in which its
ownership or lease of property or the nature of its businesses makes such
license or qualification necessary (except as otherwise permitted under Section
7.04 and except for such other jurisdictions in which such failure to be so
licensed or qualified individually and in the aggregate would not result in a
Material Adverse Change).

        6.02. Accounting System; Reporting Requirements. The Borrower will
              ----------------------------------------- 
maintain, and will cause its Subsidiaries to maintain, a system of accounting
established and administered in accordance with GAAP, and will and will cause
its Subsidiaries to set aside on its books all such proper reserves as shall be
required by GAAP. Further, the Borrower will:

              (a) deliver to the Agent, for redelivery to the Lenders, within
forty-five (45) days after the end of each of the first three (3) Fiscal
Quarters in each Fiscal Year of the Borrower, (A) consolidated balance sheet as
at the end of such period for the Borrower and its Subsidiaries, (B)
consolidated statements of income for such period for the Borrower and its
Subsidiaries and, in the case of the second and third quarterly periods, for the
period from the beginning of the current Fiscal Year to the end of such
quarterly period, and (C) consolidated statements of cash flow for such period
for the Borrower and its Subsidiaries and, in the case of the second and third
quarterly periods, for the period from the beginning of the current Fiscal Year
to the end of such quarterly period; and each such statement shall set forth, in
comparative form, corresponding figures for the corresponding period in the
immediately preceding Fiscal Year; and all such statements shall be prepared in
reasonable detail and certified, subject to changes resulting from year-end
adjustments, by the chief financial officer, treasurer or controller of the
Borrower;

              (b) deliver to the Agent, for redelivery to the Lenders, within 90
days after the end of each Fiscal Year of the Borrower, (A) consolidated balance
sheets as at the end of such year for the Borrower and its Subsidiaries, (B)
consolidated statements of income for such year for the Borrower and its
Subsidiaries, (C) consolidated statements of cash flow for such year for the
Borrower and its Subsidiaries, and (D) consolidated statements of shareholders
equity for such year for the Borrower and its Subsidiaries; and each such
statement shall set forth, in comparative form, corresponding figures for the
immediately preceding Fiscal Year; and all such financial statements shall
present fairly in all material respects the financial position of the Borrower
and its consolidated Subsidiaries, as at the dates indicated and the results of
its operations and its cash flow for the periods indicated, in conformity with
GAAP; and the Borrower shall cause each of the consolidated financial statements
described in clauses (A) through (D) of this Section 6.02(b) to be certified
without limitation as to scope or material qualification by Arthur Andersen
L.L.P. or other independent certified public accountants acceptable to the
Required Lenders;

              (c) deliver to the Agent, together with each delivery of financial
statements pursuant to items (a) and (b) above for redelivery to the Lenders, a
Compliance Certificate of the Borrower substantially in the form of Exhibit
                                                                    ------- 
"E" hereto, properly completed and signed by the chief financial officer,
---
treasurer or controller of the Borrower, (A) stating (1) that such officer has
reviewed the terms of the Loan Documents and has made, or caused to
<PAGE>
 
be made under his supervision, a review of the transactions and condition of the
Borrower and its Subsidiaries during the accounting period covered by such
financial statements and that such review has not disclosed the existence during
such accounting period, and (2) that the Borrower does not have knowledge of the
existence, as at the date of such Compliance Certificate, of any condition or
event which constitutes an Event of Default or a Default, or, if any such
condition or event existed or exists, specifying the nature and period of
existence thereof and what action the Borrower has taken or is taking or
proposes to take with respect thereto, and (B) demonstrating in reasonable
detail compliance as at the end of such accounting period with the restrictions
contained in Section 7.12 hereof;

              (d) promptly give written notice to the Agent, for redelivery to
the Lenders, of the happening of any event (which is known to the Borrower)
which constitutes an Event of Default or a Default hereunder, but in no event
shall any such notice be given later than five (5) Business Days after the
Borrower knows or should have known of such event;

              (e) promptly give written notice to the Agent, for redelivery to
the Lenders, of any pending or, to the knowledge of the Borrower, overtly
threatened claim in writing, litigation or threat of litigation which arises
between the Borrower, or any of its Subsidiaries, and any other party or parties
(including, without limitation, any Official Body) which claim, litigation or
threat of litigation, individually or in the aggregate, is reasonably likely to
cause a Material Adverse Change, any such notice to be given not later than five
(5) Business Days after any of the Borrower becomes aware of the occurrence of
any such claim, litigation or threat of litigation;

              (f) promptly deliver to the Agent, but in no event later than
twenty (20) days after the mailing or filing thereof, for redelivery to the
Lenders, copies of (A) all reports, notices and proxy statements sent by the
Borrower to its shareholders, and (B) all regular and periodic reports and
definitive proxy materials (including but not limited to Forms 10-K, 10-Q and 8-
K) filed by the Borrower with any securities exchange or the Federal Securities
and Exchange Commission;

              (g) promptly deliver to the Agent, but in no event later than
twenty (20) days after Borrower receives the same, for redelivery to the
Lenders, copies of any management letters addressed to the Borrower by its
independent certified public accountant; and

              (h) such other reports and information as the Agent or the
Required Lenders may from time to time reasonably request.

        6.03. Notices Regarding Plans and Benefit Arrangements.
              ------------------------------------------------   

              (a) Promptly upon becoming aware of the occurrence thereof, notice
(including the nature of the event and, when known, any action taken or
threatened by the Internal Revenue Service or the PBGC with respect thereto)
shall be given to the Agent, for redelivery to the Lenders, by the Borrower of:

                  (i) any Reportable Event with respect to the Borrower or any
member of the ERISA Group,
<PAGE>
 
                  (ii) any Prohibited Transaction which could subject the
Borrower or any member of the ERISA Group to a civil penalty assessed pursuant
to Section 502(i) of ERISA or a tax imposed by Section 4975 of the Internal
Revenue Code in connection with any Plan, Benefit Arrangement or any trust
created thereunder, if such tax and/or penalty is reasonably likely to result in
a Material Adverse Change,

                  (iii) any assertion of material withdrawal liability with
respect to any Multiemployer Plan,

                  (iv) any partial or complete withdrawal from a Multiemployer
Plan by the Borrower or any member of the ERISA Group under Title IV of ERISA
(or assertion thereof), where such withdrawal is likely to result in material
withdrawal liability,

                  (v) any cessation of operations (by the Borrower of any member
or the ERISA Group) at a facility in the circumstances described in Section
4062(e) of ERISA,

                  (vi) withdrawal by the Borrower or any member of the ERISA
Group from a Multiple Employer Plan,

                  (vii) a failure by the Borrower or any member of the ERISA
Group to make a payment to a Plan required to avoid imposition of a lien under
Section 302(f) of ERISA,

                  (viii) the adoption of an amendment to a Plan requiring the
provision of security to such Plan pursuant to Section 307 of ERISA, or

                  (ix) any change in the actuarial assumptions or funding
methods used for any Plan, where the effect of such change is to materially
increase or materially reduce the unfunded benefit liability or obligation to
make periodic contributions.

              (b) Promptly after receipt thereof, copies of (i) all notices
received by the Borrower or any member of the ERISA Group of the PBGC's intent
to terminate any Plan administered or maintained by the Borrower or any member
of the ERISA Group, or to have a trustee appointed to administer any such Plan;
and (ii) at the request of the Agent or any Lender each annual report (IRS Form
5500 series) and all accompanying schedules, the most recent actuarial reports,
the most recent financial information concerning the financial status of each
Plan administered or maintained by the Borrower or any member of the ERISA
Group, and schedules showing the amounts contributed to each such Plan by or on
behalf of the Borrower or any member of the ERISA Group in which any of their
respective personnel participate or from which such personnel may derive a
benefit, and each Schedule B (Actuarial Information) to the annual report filed
by the Borrower or any member of the ERISA Group with the Internal Revenue
Service with respect to each such Plan shall be given to the Agent by the
Borrower, for redelivery to the Lenders.
<PAGE>
 
              (c) Promptly upon the filing thereof, copies of any PBGC Form 200,
500, 600 or 601, or any successor form, filed with the PBGC in connection with
the termination of any Plan, for redelivery to the Lenders.

        6.04. Payment of Liabilities, Including Taxes, etc.    The
              --------------------------------------------        
Borrower shall duly pay and discharge, and shall cause its Subsidiaries to pay
and discharge (subject, where applicable, to specified grace periods and, in the
case of trade payables, to normal payment practices) promptly as and when the
same shall become due and payable, all liabilities which singularly are in
excess of $100,000 or which in the aggregate exceed $500,000 to which they are
subject or which are asserted against them, including all taxes, assessments and
governmental charges upon them or any of their properties, assets, income or
profits, prior to the date on which penalties attach thereto; provided, however,
                                                              --------  ------- 
the Borrower may choose not to pay any such liabilities, including taxes,
assessments or charges, if the same are being contested in good faith and for
which such reserves (including reserves for any additional amounts which would
be payable as a result of the failure to discharge timely any such liabilities)
or other appropriate provisions, if any, as shall be required by GAAP shall have
been made.

        6.05.  Maintenance of Insurance. The Borrower shall insure,
               ------------------------
and shall cause its Subsidiaries to insure, their respective properties and
assets against loss or damage in such amounts as similar properties and assets
are insured by prudent companies in similar circumstances carrying on similar
businesses, and with reputable and financially sound insurers, including self-
insurance to the extent customary. The Borrower will furnish to the Agent for
redelivery to the Lenders on the Closing Date and thereafter simultaneously with
the delivery of the annual financial information delivered pursuant to Section
6.02(b) a certificate of the Borrower executed by an Authorized Officer of the
Borrower certifying that such insurance is in force, is adequate in nature and
amount and complies with the Borrower's obligations under this Section 6.05.

        6.06. Maintenance of Properties and Leases. The Borrower and
              ------------------------------------                    
its Subsidiaries shall maintain in good repair, working order and condition
(ordinary wear and tear excepted) in accordance with the general practice of
other businesses of similar character and size, all of those properties useful
or necessary to their respective businesses, and from time to time, the Borrower
will make or cause to be made all appropriate repairs, renewals or replacements
thereof.

        6.07. Maintenance of Permits and Franchises. The Borrower
              -------------------------------------                
and its Subsidiaries shall maintain in full force and effect all franchises,
permits and other authorizations necessary for the ownership and operation of
their respective properties and business if the failure so to maintain the same,
individually or in the aggregate, would constitute a Material Adverse Change.

        6.08. Visitation Rights. The Borrower shall permit, and
              -----------------                                  
shall cause its Subsidiaries to permit, any of the officers or authorized
employees or representatives of the Agent or any of the Lenders to visit and
inspect any of the properties of the Borrower, or a Subsidiary of the Borrower,
and to examine and make excerpts from its books and records and discuss its
respective business affairs, finances and accounts with its officers, all in
such detail and at such times and as often as any of the Lenders may reasonably
request, provided that
<PAGE>
 
each Lender shall provide the Borrower, or the Subsidiary of the Borrower, as
the case may be, and the Agent with reasonable notice prior to any visit or
inspection and that only the Agent and its authorized employees or
representatives are permitted to conduct audits. After the occurrence of an
Event of Default and during the continuance thereof the Agent and the Lenders
shall have the right of visitation and inspection without prior notice.

        6.09. Keeping of Records and Books of Account. The Borrower,
              ---------------------------------------                 
and its Subsidiaries, shall maintain and keep proper books of record and account
which enable the Borrower to issue financial statements in accordance with GAAP
and as otherwise required by applicable Laws of any Official Body having
jurisdiction over the Borrower and its Subsidiaries, and in which full, true and
correct entries shall be made in all material respects of all their respective
dealings and business and financial affairs.

        6.10. Plans and Benefit Arrangements. The Borrower shall,
              ------------------------------                       
and shall cause each member of the ERISA Group to, comply with ERISA, the
Internal Revenue Code and other applicable Laws applicable to Plans and Benefit
Arrangements except where such failure, alone or in conjunction with any other
failure, would not result in a Material Adverse Change. Without limiting the
generality of the foregoing, the Borrower shall cause all of its Plans and all
Plans maintained by any member of the ERISA Group to be funded in accordance
with the minimum funding requirements of ERISA and shall make, and cause each
member of the ERISA Group to make, in a timely manner, all contributions due to
Plans, Benefit Arrangements and Multiemployer Plans.

        6.11. Compliance with Laws. The Borrower and its Subsidiaries shall
              -------------------- 
comply with all applicable Laws (other than Environmental Laws) in all respects,
provided that they shall not be deemed to be a violation of this Section 6.11 if
any failure to comply with any Law would not result in fines, penalties, other
similar liabilities or injunctive relief which in the aggregate would constitute
a Material Adverse Change.

        6.12. Use of Proceeds. The Borrower will use the proceeds of
              ---------------                                         
the Loans only for lawful purposes in accordance with Section 2.17 hereof as
applicable and such uses shall not contravene any applicable Law or any other
provision hereof. The Borrower will permit the use of the Letters of Credit only
for lawful purposes in accordance with Section 2.18 hereof as applicable, and
such uses shall not contravene any applicable Law or any other provision hereof.
The Borrower and its Subsidiaries shall not use any portion of the proceeds of
the Loans, directly or indirectly, to purchase during the underwriting period,
or for thirty (30) days thereafter, Ineligible Securities being underwritten by
a Section 20 Subsidiary.

        6.13. Environmental Laws.
              ------------------   

              (i) The Borrower and its Subsidiaries shall comply in all material
respects, subject to the disclosure set forth in Schedule 4.20, with all
                                                 -------------
Environmental Laws and shall obtain and comply in all material respects with and
maintain any and all licenses, approvals, registrations or permits required by
Environmental Laws;

              (ii) The Borrower and its Subsidiaries shall conduct and complete
in all material respects all investigations, studies, sampling and testing, and
all remedial, removal and other actions required under Environmental Laws and
promptly comply in all material
<PAGE>
 
respects with all lawful orders and directives of all Official Bodies respecting
Environmental Laws, except to the extent that the same are being contested in
good faith by appropriate and lawful proceedings diligently conducted and for
which such reserves or other appropriate provisions, if any, required by GAAP
shall have been made; and

              (iii) The Borrower shall defend, indemnify and hold harmless the
Agent and the Lenders, and their respective employees, agents, officers and
directors, from and against any claims, demands, penalties, fines, liabilities,
settlements, damages, costs and expenses of whatever kind or nature known or
unknown, contingent or otherwise, arising out of, or in any way relating to the
violation of or noncompliance with any Environmental Laws applicable to the real
property owned or operated by the Borrower or any of its Subsidiaries, or any
orders, requirements or demands of any Official Bodies related thereto,
including, without limitation, reasonable attorney's and consultant's fees,
investigation and laboratory fees, court costs and litigation expenses, except
to the extent that any of the foregoing arise out of the gross negligence or
willful misconduct of the party seeking indemnification therefor.

        6.14. Senior Debt Status. The obligations of the Borrower
              ------------------                                   
under this Agreement and the Notes will rank at least pari passu in priority of
payment with all other Indebtedness of the Borrower except Indebtedness of the
Borrower to the extent secured by Permitted Liens. The obligations of each other
Loan Party under a Subsidiary Guaranty executed by it will rank at least pari
passu in priority of payment with all other Indebtedness of such Loan Party
except Indebtedness of such Loan Party to the extent secured by Permitted Liens.

                                  ARTICLE VII
                               NEGATIVE COVENANTS
                               ------------------

  The Borrower covenants and agrees that, until payment in full of the Loans and
interest thereon, payment in full of all Letter of Credit reimbursement
obligations and interest thereon, satisfaction of all of the Borrower's other
obligations hereunder and termination of the Revolving Credit Commitments, and
the expiration and cancellation of all Letters of Credit issued hereunder, the
Borrower shall comply, or cause the compliance, with the negative covenants set
forth in this Article VII.

        7.01. Indebtedness. The Borrower and its Subsidiaries shall
              ------------                                           
not on a consolidated basis at any time, create, incur, assume or suffer to
exist any Indebtedness (including Indebtedness secured by Permitted Liens),
except:

              (a) Indebtedness under the Loan Documents;

              (b) Existing Indebtedness as set forth on Schedule 7.01 hereto
                                                        -------------
(including any extensions or renewals thereof provided there is no increase in
the amount thereof or other significant adverse change in the terms thereof);

              (c) Indebtedness of a Subsidiary of the Borrower to the Borrower
or to another Subsidiary of the Borrower or the Indebtedness of the Borrower to
a Subsidiary of the Borrower;
<PAGE>
 
              (d) Indebtedness with respect to foreign exchange hedging
transactions entered into in the ordinary course of business to manage foreign
currency risk for the Borrower and/or one or more of its Subsidiaries;

              (e) Indebtedness incurred pursuant to Interest Hedge Agreements;

              (f) Indebtedness due sellers of Persons or assets acquired
pursuant to Sections 7.03 or 7.04 hereof, including without limitation notes the
principal amount of which may vary as a function of the performance of the
Person or assets acquired; and

              (g) Other Indebtedness not covered by items (a) through (f) above,
provided that the aggregate amount of such Indebtedness permitted by this item
(g) shall not exceed $10,000,000 at any one time outstanding.

        7.02.  Liens. The Borrower and its Subsidiaries shall not at
               -----                                                  
any time create, incur, assume or suffer to exist any Lien on any of their
respective property or assets, tangible or intangible, now owned or hereafter
acquired, or agree or become liable to do so, except Permitted Liens. Further,
neither the Borrower nor any of its Subsidiaries shall enter into any agreement
with any Person (other than the Lenders pursuant hereto) which prohibits or
limits the ability of the Borrower or any of its Subsidiaries to create, incur,
assume or suffer to exist any Lien in favor of the Agent for the benefit of the
Lenders upon any of its property, assets or revenues, whether now owned or
hereafter acquired.

        7.03. Loans, Acquisitions and Investments. The Borrower and
              -----------------------------------                    
its Subsidiaries shall not at any time make any loan or advance to, or purchase
or otherwise acquire any stock, bonds, notes or securities of, or any
partnership interest (whether general or limited) or other equity interest in,
or assets of, or any other investment or interest in, or make any capital
contribution to, any other Person, or agree to or become liable to do any of the
foregoing, except for:

              (a) trade credit extended on usual and customary terms in the
ordinary course of business;

              (b) fixed assets, equipment or Inventory acquired in the ordinary
course of business;

              (c) loans and advances to employees to meet expenses incurred by
such employees in the ordinary course of business, including without limitation
relocation expenses;

              (d) Cash Equivalents;

              (e) investments, capital contributions and advances by the
Borrower in existence as of the date hereof, which investments, capital
contributions and advances are set forth on Schedule 7.03 hereof;
                                            -------------

              (f) investments and capital contributions by the Borrower in, and
loans and advances by Borrower to, a third Person so long as after giving effect
to each such
<PAGE>
 
investment or capital contribution the Borrower shall not have caused a
violation of the Loan Documents;

              (g) loans, advances and capital contributions by a Subsidiary of
the Borrower to the Borrower or any of the Borrower's other Subsidiaries or
loans, advances and capital contributions by the Borrower to any of its
Subsidiaries; and

              (h) the Borrower or any Subsidiary may acquire the assets or
securities of any other Person provided that (A) at the time of such acquisition
no Default or Event of Default shall have occurred and be continuing or be
caused by such acquisition, (B) the acquired Person, if a domestic Person, shall
become a Subsidiary Guarantor simultaneously with such acquisition and shall
execute all Loan Documents required of a Subsidiary Guarantor, (C) the
Borrower's or the relevant Subsidiary's equity ownership interest in the
acquired Person, if a foreign Person owned by a domestic Subsidiary, shall be
pledged to the Agent for the benefit of the Lenders; provided, however, the
                                                     -----------------
maximum amount of such acquired Person's equity pledged to the Agent shall not
exceed 65% of the acquired Person's equity capitalization or such lesser amount
as is the maximum amount allowed to be pledged pursuant to the laws of the
jurisdiction of such Subsidiary's organization, (D) the board of directors or
other equivalent governing body of such acquired Person shall have approved such
acquisition, (E) the acquired Person is engaged in the information technology
business or a business related thereto, and (F) the Borrower shall have provided
the Agent, for redelivery to the Lenders, at least three (3) Business Days prior
to such acquisition, with a certificate stating that (i) such acquisition will
not violate any covenants of this Agreement and (ii) establishing that, on a pro
forma basis after taking into account the acquisition, the Borrower is in
compliance with the financial covenants set forth in Section 7.12; provided,
                                                                   --------
however, for the purposes of this Section 7.03, the ratio of the Borrower's pro
-------
forma Consolidated Senior Indebtedness to pro forma Consolidated EBITDA for the
four (4) most recently completed Fiscal Quarters shall not exceed 1.75:1.00.

        7.04. Liquidations, Mergers and Consolidations. The Borrower
              ----------------------------------------                
shall not, and shall not permit any Subsidiary of Borrower to, dissolve,
liquidate or wind-up its affairs, or become a party to any merger, consolidation
or other business combination, whether accounted for under GAAP as a purchase or
a pooling of interests and regardless of whether the value of the consideration
paid or received is comprised of cash, common or preferred stock or other equity
interests, or other assets, or sell, lease, transfer, or otherwise dispose of
all or substantially all of its assets, provided that:
                                        --------      

              (a) any Subsidiary of Borrower may consolidate or merge into the
Borrower or another Subsidiary of the Borrower;

              (b) any Subsidiary of the Borrower may sell, lease, transfer or
otherwise dispose of all or substantially all of its assets (upon voluntary
liquidation or otherwise) to the Borrower or another Subsidiary of the Borrower;
and

              (c) the Borrower or any Subsidiary may consolidate or merge with
any Person, provided that (A) such Person must be engaged in the information
technology business or a business related thereto, (B) if the Borrower is a
party to such merger or consolidation, the Borrower is the surviving Person, (C)
at the time of the consolidation or
<PAGE>
 
merger no Default or Event of Default shall have occurred and be continuing or
be caused by such consolidation or merger, (D) the surviving Person, if a
domestic Person and if not the Borrower, shall become a Subsidiary Guarantor,
(E) the consolidation or merger shall not be contested by such Person and shall
be approved by such Person's board of directors or other governing body, and (F)
the Borrower shall have provided the Agent, for redelivery to the Lenders, at
least three (3) Business Days prior to such merger or consolidation, with a
certificate stating that (i) such merger or consolidation will not violate any
covenants of this Agreement and (ii) establishing that, on a pro forma basis
after taking into account such merger or consolidation, the Borrower is in
compliance with the financial covenants set forth in Section 7.12; provided,
                                                                   --------
however, for the purposes of this Section 7.04, the ratio of the Borrower's pro
-------
forma Consolidated Senior Indebtedness to pro forma Consolidated EBITDA for the
four (4) most recently completed Fiscal Quarters shall not exceed 1.75:1.00.

        7.05.  Dispositions of Assets or Subsidiaries. Excluding the
               --------------------------------------                 
payment of cash as consideration for assets purchased by, or services rendered
to, the Borrower or any Subsidiary, neither the Borrower nor any of its
Subsidiaries shall sell, convey, assign, lease, or otherwise transfer or dispose
of, voluntarily or involuntarily, any of its properties or assets, tangible or
intangible (including but not limited to sale, assignment, discount or other
disposition of Receivables, contract rights, chattel paper, equipment or general
intangibles with or without recourse or of capital stock, shares or beneficial
interests or partnership interests in Subsidiaries), except:

              (a) any sale, transfer or disposition of surplus, obsolete or worn
out assets of the Borrower or a Subsidiary;

              (b) any sale, transfer or lease of inventory by the Borrower or
any Subsidiary of the Borrower in the ordinary course of business;

              (c) any sale, transfer or lease of assets by any Subsidiary of the
Borrower to the Borrower or any other Subsidiary of the Borrower or by the
Borrower to any Subsidiary of the Borrower; or

              (d) any sale, transfer or lease of assets, other than those
specifically excepted pursuant to clauses (a) through (c) above, which in any
one sale, transfer or lease of assets, or in any number of sales, transfers or
leases of assets occurring in any consecutive twelve month period, involves the
sale, transfer or lease of assets resulting in net proceeds of not more than
$1,000,000 (measured with respect to a series of sales, transfers or leases of
assets on the day of the first sale).

        7.06. Affiliate Transactions. Except as set forth on Schedule 4.02 and
              ----------------------                         -------------  
as set forth on Schedule 7.06, neither the Borrower nor any Subsidiary of the
                -------------
Borrower shall enter into or carry out any material transaction (including,
without limitation, purchasing property or services or selling property or
services) with an Affiliate which is not a Subsidiary unless such transaction is
not otherwise prohibited by this Agreement or the other Loan Documents, is
entered into in the ordinary course of business upon fair and reasonable arm's-
length terms and conditions which are fully disclosed to the Agent and is in
accordance with all applicable Law.
<PAGE>
 
        7.07. Subsidiaries, Partnerships and Joint Ventures.   Except
              ---------------------------------------------          
as permitted by Sections 7.03 and 7.04, (i) neither the Borrower nor any
Subsidiary of the Borrower shall own or create any Subsidiaries other than those
listed in Schedule 4.03 or 7.03; and (ii) neither the Borrower nor any
          ---------------------                                       
Subsidiary of the Borrower shall become or agree to become a general partner in
any general or limited partnership or a joint venturer in any joint venture,
without the consent of the Required Lenders, such consent not to be unreasonably
withheld.

        7.08. Continuation of or Change in Business. Neither the
              -------------------------------------               
Borrower nor any Subsidiary of the Borrower shall engage in any business other
than the information technology business or a business related thereto, and the
Borrower shall not permit any material change in such business.

        7.09. Plans and Benefit Arrangements. The Borrower shall not, and shall
              ------------------------------ 
not permit any member of the ERISA Group to:

              (a) fail to satisfy the minimum funding requirements of ERISA and
the Internal Revenue Code with respect to any Plan;

              (b) request a minimum funding waiver from the Internal Revenue
Service with respect to any Plan;

              (c) engage in a Prohibited Transaction with any Plan, Benefit
Arrangement or Multiemployer Plan which, alone or in conjunction with any other
circumstances or set of circumstances resulting in liability under ERISA, would
constitute a Material Adverse Change;

              (d) fail to make when due any contribution to any Multiemployer
Plan that the Borrower or any member of the ERISA Group may be required to make
under any agreement relating to such Multiemployer Plan, or any Law pertaining
thereto;

              (e) withdraw (completely or partially) from any Multiemployer Plan
or be deemed under Section 4062(e) of ERISA to withdraw from any Multiple
                   ---------------
Employer Plan, where any such withdrawal is likely to result in a material
liability of the Borrower or any member of the ERISA Group;

              (f) terminate, or institute proceedings to terminate, any Plan,
where such termination is likely to result in a material liability to the
Borrower or any member of the ERISA Group;

              (g) make any amendment to any Plan with respect to which security
is required under Section 307 of ERISA; or

              (h) fail to give any and all notices and make all disclosures and
governmental filings required under ERISA or the Internal Revenue Code, where
such failure is likely to result in a Material Adverse Change.
<PAGE>
 
        7.10. Fiscal Year. Neither the Borrower nor any Subsidiary
              -----------                                           
of the Borrower shall change its Fiscal Year from a period beginning January 1
and ending on the immediately succeeding December 31.

        7.11. Changes in Organizational Documents. The Borrower
              -----------------------------------                
shall not, and shall not permit any other Loan Party to, amend in any respect
its certificate or articles of incorporation without providing at least ten (10)
calendar days' prior written notice to the Agent and the Lenders and, in the
event such change would be materially adverse to the Lenders as determined by
the Agent in its sole but reasonable discretion, obtaining the prior written
consent of the Required Lenders.

        7.12.  Financial Covenants.
               -------------------   

               (a) Minimum Consolidated Net Worth. The Borrower will not at any
                   ------------------------------
time permit its Consolidated Net Worth to be less than an amount equal to the
sum of (i) $123,940,000 plus (ii) 50% of the positive Consolidated Net Income
for the Fiscal Quarter ending December 31, 1998, plus (iii) 50% of the positive
Consolidated Net Income for each Fiscal Year ending after December 31, 1998,
plus (iv) an amount equal to 100% of net cash proceeds from the issuance by the
Borrower after September 30, 1998, of additional equity securities or other
equity capital investments.

              (b) Interest Coverage. As of the last day of each Fiscal Quarter,
                  -----------------
the Borrower shall not permit its ratio, measured on a rolling four Fiscal
Quarter basis, of Consolidated EBIT to Consolidated Interest Expense to be less
than 5.0:1.0.

              (c) Consolidated Senior Indebtedness to Consolidated EBITDA Ratio.
                  -------------------------------------------------------------
As of the last day of each Fiscal Quarter, the Borrower shall not permit its
Consolidated Senior Indebtedness to Consolidated EBITDA Ratio to exceed 2.5 to
1.0.

              (d) Liquidity Ratio. As of the last day of each Fiscal Quarter,
                  --------------- 
the Borrower shall not permit the ratio of the (A) the sum of its (1)
Consolidated Cash, (2) Consolidated Cash Equivalents, and (3) Consolidated
Receivables to (B) its Consolidated Senior Indebtedness to be less than
1.25:1.00.

                                  ARTICLE VIII
                                    DEFAULT
                                    -------

        8.01. Events of Default. An "Event of Default" shall mean
              -----------------                                    
the occurrence or existence of any one or more of the following events or
conditions (whatever the reason therefor and whether voluntary, involuntary or
effected by operation of Law):

              (a) (i) The Borrower shall fail to pay any principal of any Loan
(including scheduled installments, mandatory prepayments or the payment due at
maturity, whether by acceleration or otherwise) when due, or (ii) the Borrower
shall fail to pay any Unreimbursed L/C Draw when due, or (iii) the Borrower
shall fail to pay any interest on any Loan, any Unreimbursed L/C Draw, any Fee,
or any other amount owing hereunder or under any other Loan Documents after such
interest, Fee or other amount becomes due in
<PAGE>
 
accordance with the terms hereof or thereof and such failure shall continue for
a period of five (5) days;

              (b) Any representation or warranty made at any time by the
Borrower herein or in any other Loan Document or by any other Loan Party in any
Loan Document executed by such Loan Party, or in any certificate, other
instrument or statement furnished pursuant to the provisions hereof or thereof,
shall prove to have been false or misleading in any material respect as of the
time it was made or furnished;

              (c) The Borrower shall default in the observance or performance of
any covenant contained in Section 6.14 or Article VII hereof;

              (d) The Borrower shall default in the observance or performance of
any other covenant, condition or provision hereof, or of any other Loan Document
and, if remediable, such default shall continue unremedied for a period of
thirty (30) days after any officer of the Borrower becomes aware of the
occurrence thereof; or any other Loan Party shall default in the observance or
performance of any other covenant, condition or provision contained in any other
Loan Document executed by such Loan Party, and such default shall continue
unremedied for a period of thirty (30) days after any officer of such Loan Party
becomes aware of the occurrence thereof;

              (e) A default or event of default shall occur at any time under
the terms of any agreements involving Indebtedness under which the Borrower or
any Subsidiary of the Borrower may be obligated as borrower, guarantor or
otherwise in excess of One Million Dollars ($1,000,000) in the aggregate, and
such breach, default or event of default consists of the failure to pay (beyond
any period of grace permitted with respect thereto, whether waived or not) any
Indebtedness when due (whether at stated maturity, by acceleration or otherwise)
or if such breach or default causes the acceleration of any such Indebtedness or
such breach or default permits the acceleration of any Indebtedness;

              (f) Any judgments or orders for the payment of money in excess of
One Million Dollars ($1,000,000) in the aggregate shall be entered against the
Borrower or any of its Subsidiaries, by a court having jurisdiction in the
premises which judgments are not satisfied, discharged, vacated, bonded or
stayed pending appeal within a period of thirty (30) days from the respective
date of entry;

              (g) Any of the Loan Documents shall cease to be legal, valid and
binding agreements enforceable against the party executing the same or such
party's successors and assigns (as permitted under the Loan Documents) in
accordance with the respective terms thereof (except to the extent that
enforceability of any of the Loan Documents may be limited by bankruptcy,
insolvency, reorganization, moratorium or other similar laws affecting the
enforceability of creditors' rights generally or limiting the right of specific
performance) or shall in any way be terminated (except in accordance with terms)
or become or be declared ineffective or inoperative or shall in any way be
challenged or contested or cease to give or provide the respective rights,
titles, interests, remedies, powers or privileges intended to be created thereby
in all material respects;
<PAGE>
 
              (h) A notice of lien, levy or assessment in excess of One Million
Dollars ($1,000,000) in the aggregate is filed of record with respect to all or
any part of the assets of the Borrower or a Subsidiary Guarantor by the United
States, or any department, agency or instrumentality thereof, or by any state,
county, municipal or other governmental agency, including, without limitation,
the PBGC, or if any taxes or debts in excess of One Million Dollars ($1,000,000)
owing at any time or times hereafter to any one of these becomes payable and the
same is not paid within thirty (30) days after the same becomes payable, or if
such notice is filed or such payment is not so made, unless the Borrower or such
Subsidiary Guarantor (i) contests such lien, assessment, tax or debt in good
faith by appropriate and lawful proceedings diligently conducted but only so
long as such proceedings could not subject the Agent, the Lenders or the L/C
Issuer to any criminal penalties, (ii) establishes such reserves or other
appropriate provisions, if any, as shall be required by GAAP and (iii) pays such
Lien, assessment, tax or debt in accordance with the terms of any final
judgments or orders relating thereto within thirty (30) days after the entry of
such judgments or orders;

              (i) The Borrower or any other Loan Party ceases to be Solvent or
admits in writing its inability to pay debts as they mature;

              (j) Any of the following occurs: (i) any Reportable Event, which
constitutes grounds for the termination of any Plan by the PBGC or the
appointment of a trustee to administer or liquidate any Plan, shall have
occurred and be continuing; (ii) proceedings shall have been instituted or other
action taken to terminate any Plan, or a termination notice shall have been
filed with respect to any Plan; (iii) a trustee shall be appointed to administer
or liquidate any Plan; (iv) the PBGC shall give notice of its intent to
institute proceedings to terminate any Plan or Plans or to appoint a trustee to
administer or liquidate any Plan and, in the case of the occurrence of (i),
(ii), (iii) or (iv) of this Section 8.01(j), the amount of Borrower's liability
or the liability of the other members of the ERISA Group is likely to exceed
five percent (5%) of the Consolidated Net Worth; (v) the Borrower or any member
of the ERISA Group shall fail to make any contributions when due to a Plan or a
Multiemployer Plan; (vi) the Borrower or any member of the ERISA Group shall
make any amendment to a Plan with respect to which security is required under
Section 307 of ERISA; (vii) the Borrower or any member of the ERISA Group shall
withdraw completely or partially from a Multiemployer Plan; (viii) the Borrower
or any member of the ERISA Group shall withdraw (or shall be treated under
Section 4062(e) of ERISA as having withdrawn) from a Multiple Employer Plan; or
(ix) any applicable Law is adopted, changed or interpreted by any Official Body
with respect to or otherwise affecting one or more Plans, Multiemployer Plans or
Benefit Arrangements and, with respect to any of the events specified in (v),
(vi), (vii), (viii) or (ix), any such occurrence would be reasonably likely to
materially and adversely affect the total enterprise represented by the Borrower
and the other members of the ERISA Group;

              (k) The Borrower or any other Loan Party is enjoined, restrained
or in any way prevented by court order from conducting all or any material part
of its business and such injunction, restraint or other preventive order is not
stayed or dismissed within thirty (30) days after the entry thereof;

              (l) (i) except for the Founding Shareholders and their Affiliates,
any Person or group of Persons (within the meaning of Sections 13(g) or 14(d)(2)
of the Securities Exchange Act of 1934, as amended) shall have acquired
beneficial ownership of
<PAGE>
 
(within the meaning of Rule 13d-3 promulgated by the Securities and Exchange
Commission under said Act) 20% or more of the voting capital stock of the
Borrower; provided, however, so long as the Founding Shareholders or their
          -----------------
Affiliates own at least 40% of the voting capital stock of the Borrower, another
Person or group of Persons may acquire beneficial ownership of not more than 30%
of the voting capital stock of the Borrower;

                  (ii) within a period of twelve (12) consecutive months,
individuals who were directors of the Borrower on the first day of such period
and/or individuals who become directors of the Borrower pursuant to a nomination
or election that was recommended or approved by the individuals who were
directors on the first day of such period shall cease to constitute a majority
of the board of directors of the Borrower; or

                  (iii) the Borrower or a Subsidiary shall own less than 80% of
the voting capital stock or voting partnership or other equity interest of any
Loan Party other than the Borrower;

              (m) A proceeding shall have been instituted in a court having
jurisdiction in the premises seeking a decree or order for relief in respect of
the Borrower, or another Loan Party, in an involuntary case under any applicable
bankruptcy, insolvency, reorganization or other similar law now or hereafter in
effect, or a receiver, liquidator, assignee, custodian, trustee, sequestrator,
conservator (or similar official) of the Borrower, or another Loan Party, for
any substantial part of such Person's property, or for the winding-up or
liquidation of such Person's affairs, and such proceeding shall remain
undismissed or unstayed and in effect for a period of sixty (60) consecutive
days or such court shall enter a decree or order granting any of the relief
sought in such proceeding;

              (n) The Borrower, or another Loan Party, shall commence a
voluntary case under any applicable bankruptcy, insolvency, reorganization or
other similar law now or hereafter in effect, shall consent to the entry of an
order for relief in an involuntary case under any such law, or shall consent to
the appointment or taking possession by a receiver, liquidator, assignee,
custodian, trustee, sequestrator, conservator (or other similar official) of
itself or for any substantial part of property or shall make a general
assignment for the benefit of creditors, or shall fail generally to pay debts as
they become due, or shall take any action in furtherance of any of the
foregoing;

              (o) any of the Loan Documents shall cease to be in full force and
effect or shall be declared to be null and void by a court of competent
jurisdiction; or

              (p) any garnishment proceeding concerning a sum in excess of One
Million Dollars ($1,000,000) shall be instituted by attachment, levy or
otherwise, against any deposit account maintained by the Borrower or another
Loan Party with any Lender.

        8.02. Consequences of Event of Default.
              --------------------------------   

              (a) If an Event of Default specified in any of items (a) through
(l) or item (o) or (p) of Section 8.01 hereof shall occur and be continuing, the
Lenders shall be under no further obligation to make Loans hereunder, the L/C
Issuer shall be under no further obligation to issue or amend Letters of Credit
hereunder and the Agent may, and upon the
<PAGE>
 
request of the Required Lenders shall, by written notice to the Borrower,
terminate the Revolving Credit Commitment and declare the unpaid principal
amount of the Notes then outstanding and all interest accrued thereon, any
unpaid fees and all other Indebtedness of the Borrower to the Lenders, the Agent
and the L/C Issuer hereunder and under the other Loan Documents to be forthwith
due and payable, and the same shall thereupon become and be immediately due and
payable to the Agent for the benefit of each Lender, the Agent and the L/C
Issuer without presentment, demand, protest or any other notice of any kind, all
of which are hereby expressly waived; and

              (b) If any Event of Default specified in item (m) or (n) of
Section 8.01 hereof shall occur, the Lenders shall be under no further
obligations to make Loans hereunder, the L/C Issuer shall be under no further
obligation to issue or amend Letters of Credit hereunder, the Revolving Credit
Commitment shall be terminated and the unpaid principal amount of the Notes then
outstanding and all interest accrued thereon, any unpaid fees and all other
Indebtedness of the Borrower to the Lenders, the Agent and the L/C Issuer
hereunder and under the other Loan Documents shall be immediately due and
payable, without presentment, demand, protest or notice of any kind, all of
which are hereby expressly waived; further, during the sixty (60) day period
referred to in item (m) the Lenders shall be under no further obligation to make
Loans and the L/C Issuer shall be under no further obligation to issue or amend
Letters of Credit hereunder; and

              (c) If an Event of Default shall occur and be continuing, any
Lender, the Agent or the L/C Issuer to whom any obligation is owed by the
Borrower hereunder or under any other Loan Document, of such Lender, Agent or
L/C Issuer and any branch, subsidiary or affiliate of such Lender, Agent or L/C
Issuer anywhere in the world shall each have the right, in addition to all other
rights and remedies available to it, without notice to the Borrower, to set-off
against and apply to the then unpaid balance of all the Loans and all other
obligations of the Borrower hereunder or under any other Loan Document, any debt
owing to, and any other funds held in any manner for the account of, the
Borrower by such Lender, the Agent or the L/C Issuer or by such branch,
subsidiary or affiliate, including, without limitation, all funds in all deposit
accounts (whether time or demand, general or special, provisionally credited or
finally credited, or otherwise) now or hereafter maintained by the Borrower for
its own account (but not including funds held in custodian or trust accounts)
with such Lender, the Agent or the L/C Issuer or such branch, subsidiary or
affiliate. Such right shall exist in each case whether or not any Lender, the
Agent or the L/C Issuer shall have made any demand under this Agreement or any
other Loan Document, whether or not such debt owing to or funds held for the
account of the Borrower is or are matured or unmatured and regardless of the
existence or adequacy of any other security, right or remedy available to any
Lender, the Agent or the L/C Issuer; and

              (d) In addition to all of the rights and remedies contained in
this Agreement or in any of the other Loan Documents, the Agent, the L/C Issuer
and the Lenders shall have all of the rights and remedies of a creditor under
applicable Law, all of which rights and remedies shall be cumulative and non-
exclusive, to the extent permitted by Law. The Agent may, and upon the request
of the Required Lenders shall, exercise all post-default rights granted to the
Agent, the L/C Issuer and the Lenders under the Loan Documents or applicable
Law; and
<PAGE>
 
              (e) Upon the occurrence of any Event of Default described in the
foregoing Sections 8.01(m) or (n) or upon the declaration by the Required
Lenders of any other Event of Default and the termination of the Revolving
Credit Commitments, the obligation of the L/C Issuer to issue or amend Letters
of Credit shall terminate, the L/C Issuer or the Agent may provide written
demand to any beneficiary of a Letter of Credit to present a draft against such
Letter of Credit, and an amount equal to the maximum amount which may at any
time be drawn under the Letters of Credit then outstanding (whether or not any
beneficiary of such Letters of Credit shall have presented, or shall be entitled
at such time to present, the drafts or other documents required to draw under
the Letters of Credit) shall automatically become immediately due and payable,
without presentment, demand, protest or other requirements of any kind, all of
which are hereby expressly waived by the Borrower; provided that the foregoing
shall not affect in any way the obligations of the Lenders to purchase from the
L/C Issuer participations in the unreimbursed amount of any drawings under the
Letters of Credit as provided in Section 2.18(c). So long as the Letters of
Credit shall remain outstanding, any amounts declared due pursuant to this
Section 8.02(e) with respect to the outstanding Letters of Credit when received
by the Agent shall be deposited and held by the Agent in an interest bearing
account denominated in the name of the Agent for the benefit of the Agent, the
Lenders and the L/C Issuer over which the Agent shall have sole dominion and
control of withdrawals (the "Cash Collateral Account") as cash collateral for
the obligation of the Borrower to reimburse the L/C Issuer in the event of any
drawing under the Letters of Credit and upon any drawing under such Letters of
Credit in respect of which the Agent has deposited in the Cash Collateral
Account any amounts declared due pursuant to this Section 8.02(e), the Agent
shall apply such amounts held by the Agent to reimburse the L/C Issuer for the
amount of such drawing. In the event that any Letter of Credit in respect of
which the Agent has deposited in the Cash Collateral Account any amounts
described above is cancelled or expires or in the event of any reduction in the
maximum amount available at any time for drawing under the Letters of Credit
outstanding, the Agent shall apply the amount then in the Cash Collateral
Account designated to reimburse the L/C Issuer for any drawings under the
Letters of Credit less the maximum amount available at any time for drawing
under the Letters of Credit outstanding immediately after such cancellation,
expiration or reduction, if any, to the payment in full of the outstanding
Lender Obligations, and second, to the payment of any excess, to the Borrower.

                                   ARTICLE IX
                                   THE AGENT
                                   ---------

        9.01. Appointment and Grant of Authority. Each of the
              ----------------------------------               
Lenders and the L/C Issuer hereby appoints PNC Bank, National Association, and
PNC Bank, National Association, hereby agrees to act, as the Agent under this
Agreement and the other Loan Documents. The Agent shall have and may exercise
such powers under this Agreement and the other Loan Documents as are
specifically delegated to it by the terms hereof or thereof, together with such
other powers as are incidental thereto. Without limiting the foregoing, the
Agent, on behalf of the Lenders and the L/C Issuer, is authorized to execute all
of the Loan Documents (other than this Agreement) and to accept all of the Loan
Documents and all other agreements, documents or instruments reasonably required
to carry out the intent of the parties to this Agreement.

        9.02. Delegation of Duties. The Agent may perform any of its
              --------------------                                    
duties hereunder by or through agents or employees (provided such delegation
does not constitute a
<PAGE>
 
relinquishment of duties as the Agent hereunder) and, subject to Sections 9.07
and 10.03 hereof, shall be entitled to engage and pay for the advice or services
of any attorneys, accountants, or other experts concerning all matters
pertaining to duties hereunder and to rely upon any advice so obtained.

        9.03. Reliance by Agent on Lenders for Funding. Unless the
              ----------------------------------------              
Agent shall have received notice from a Lender prior to any Borrowing Date that
such Lender will not make available to the Agent such Lender's portion of net
disbursements of Loans, the Agent may assume that such Lender has made such
portion available to the Agent and the Agent may, in reliance upon such
assumption, make Loans to the Borrower. If and to the extent that such Lender
has not made such portion available to the Agent on or prior to any Borrowing
Date, such Lender and the Borrower severally agree to repay to the Agent
immediately upon demand, in immediately available funds, such unpaid amount,
together with interest thereon for each day from the applicable Borrowing Date
until such amount is repaid to the Agent, at (i) in the case of the Borrower, at
the rate of interest then in effect for such Loan and (ii) in the case of such
Lender, at the Federal Funds Effective Rate. If such Lender shall repay to the
Agent such corresponding amount, such amount shall constitute a Loan made by
such Lender for purposes of this Agreement. The failure by any Lender to pay its
portion of a Loan made by the Agent shall not relieve any other Lender of the
obligation to pay its portion of net disbursements of Loans on any Borrowing
Date, but no Lender shall be responsible for the failure of any other Lender to
make its net share of Loans to be made by such other Lender on such Borrowing
Date.

        9.04. Non-Reliance on Agent. Each Lender and the L/C Issuer
              ---------------------                                  
agree that (i) it has, independently and without reliance on the Agent, and
based on such documents and information as it has deemed appropriate, made its
own credit analysis of the Borrower and its Subsidiaries and decision to enter
into this Agreement and (ii) that it will, independently and without reliance
upon the Agent, and based on such documents and information as it shall deem
appropriate at the time, continue to make its own analysis and decisions in
taking or not taking action under this Agreement. Except as otherwise provided
herein or under any other Loan Document, the Agent shall not have any duty to
keep the Lenders or the L/C Issuer informed as to the performance or observance
by the Borrower of this Agreement or any other document referred to or provided
for herein or to inspect the properties or books of the Borrower or any of its
Subsidiaries. The Agent, in the absence of gross negligence or willful
misconduct, shall not be liable to any Lender or the L/C Issuer for their
failure to relay or furnish to the Lender any information.

        9.05. Responsibility of Agent and Other Matters.
              -----------------------------------------   

              (a) Ministerial Nature of Duties. As between the Lenders, the L/C
                  ----------------------------
Issuer and itself, the Agent shall not have any duties or responsibilities
except those expressly set forth in this Agreement or in the other Loan
Documents, and those duties and responsibilities shall be subject to the
limitations and qualifications set forth in this Article IX. The duties of the
Agent shall be ministerial and administrative in nature.

              (b) Limitation of Liability. As between the Lenders, the L/C
                  ----------------------- 
Issuer and the Agent, neither the Agent nor any of its directors, officers,
employees or agents shall be liable, in the absence of gross negligence or
willful misconduct, for any action taken or omitted
<PAGE>
 
(whether or not such action taken or omitted is within or without the Agent's
responsibilities and duties expressly set forth in this Agreement) under or in
connection with this Agreement or any other instrument or document in connection
herewith. Without limiting the foregoing, neither the Agent nor any of its
directors, officers, employees or its agents, shall be responsible for, or have
any duty to examine (i) the genuineness, execution, validity, effectiveness,
enforceability, value or sufficiency of (A) this Agreement or any of the other
Loan Documents or (B) any other document or instrument furnished pursuant to or
in connection with this Agreement, (ii) the collectability of any amounts owed
by the Borrower to the Agent, the Lenders or the L/C Issuer, (iii) the
truthfulness of any recitals or statements or representations or warranties made
to the Agent or the Lenders in connection with this Agreement, (iv) any failure
of any party to this Agreement to receive any communication sent, including any
telegram, telex, teletype, telecopy, bank wire, cable, or telephone message or
any writing, application, notice, report, statement, certificate, resolution,
request, order, consent letter or other instrument or paper or communication
entrusted to the mails or to a delivery service, or (v) the assets or
liabilities or financial condition or results of operations or business or
creditworthiness of the Borrower or any of its Subsidiaries.

              (c) Reliance. The Agent shall be entitled to act, and shall be
                  -------- 
fully protected in acting upon, any telegram, telex, teletype, telecopy, bank
wire or cable or any writing, application, notice, report, statement,
certificate, resolution, request, order, consent, letter or other instrument or
paper or communication believed by the Agent in good faith to be genuine and
correct and to have been signed or sent or made by a proper Person. The Agent
may consult counsel and shall be entitled to act, and shall be fully protected
in any action taken in good faith, in accordance with advice given by counsel.
The Agent may employee agents and attorneys-in-fact and shall not be liable for
the default or misconduct of any such agents or attorneys-in-fact selected by
the Agent with reasonable care. The Agent shall not be bound to ascertain or
inquire as to the performance or observance of any of the terms, provisions or
conditions of this Agreement or any of the other Loan Documents on the part of
the Borrower.

        9.06. Actions in Discretion of Agent; Instructions from the
              -----------------------------------------------------
Lenders. The Agent agrees, upon the written request of the Required Lenders,
-------                                                                       
to take or refrain from taking any action of the type specified as being within
the Agent's rights, powers or discretion herein or under any Loan Documents,
provided that the Agent shall not be required to take any action which exposes
the Agent to personal liability or which is contrary to this Agreement or any
other Loan Document or applicable Law. In the absence of a request by the
Required Lenders, the Agent shall have authority, in its sole discretion, to
take or not to take any such action, unless this Agreement specifically requires
the consent of the Required Lenders or all of the Lenders. Any action taken or
failure to act pursuant to such instructions or discretion shall be binding on
the Lenders and the L/C Issuer, subject to Section 9.05(b) hereof. Subject to
the provisions of Section 9.05(b), no Lender shall have any right of action
whatsoever against the Agent as a result of the Agent acting or refraining from
acting hereunder in accordance with the instructions of the Required Lenders.

        9.07. Indemnification. To the extent the Borrower does not
              ---------------                                       
reimburse and save harmless the Agent according to the terms hereof for and from
all costs, expenses and disbursements in connection herewith, such costs,
expenses and disbursements, shall be borne by the Lenders ratably in accordance
with respective Lender's Ratable Share. Each Lender hereby agrees on such basis
(i) to reimburse the Agent for such Lender's Ratable Share
<PAGE>
 
of all such reasonable costs, expenses and disbursements on request and (ii) to
the extent of each such Lender's Ratable Share, to indemnify and save harmless
the Agent against and from any and all losses, obligations, penalties, actions,
judgments and suits and other costs, expenses and disbursements of any kind or
nature whatsoever which may be imposed on, incurred by or asserted against the
Agent, other than as a consequence of gross negligence or willful misconduct on
the part of the Agent, arising out of or in connection with this Agreement, the
other Loan Documents or any other agreement, instrument or document in
connection herewith or therewith, or any request of the Required Lenders,
including without limitation the reasonable costs, expenses and disbursements in
connection with defending itself against any claim or liability related to the
exercise or performance of any of its powers or duties under this Agreement, the
other Loan Documents, or any of the other agreements, instruments or documents
delivered in connection herewith or the taking of any action under or in
connection with any of the foregoing.

        9.08. Agent's Rights as Lender. With respect to the Revolving Credit
              ------------------------
Commitment of the Agent as Lender hereunder, any Loans of the Agent under this
Agreement, the Agent's Ratable Share of any Unreimbursed L/C Draws, the
participation as a Lender, and as to PNC Bank, as the L/C Issuer under this
Agreement the other Loan Documents and any other agreements, instruments and
documents delivered pursuant hereto, and the issuance of any Letter of Credit
under the terms hereof, the Agent shall have the same rights and powers, duties
and obligations under this Agreement, the other Loan Documents or any other
agreement, instrument or document as any Lender and may exercise such rights and
powers and shall perform such duties and fulfill such obligations as though it
were not the Agent. The Agent may accept deposits from, lend money to, and
generally engage, and continue to engage, in any kind of business with the
Borrower or any of its Subsidiaries.

        9.09. Notice of Default. The Agent shall not be deemed to
              -----------------                                    
have knowledge or notice of the occurrence of an Event of Default unless the
Agent has received written notice from a Lender or the Borrower referring to
this Agreement, describing such Event of Default and stating that such notice is
a "notice of default".

        9.10.  Payment to Lenders. Except as otherwise set forth in
               ------------------                                    
Section 9.03 hereof, promptly after receipt from the Borrower of any principal
repayment of the Loans or any Unreimbursed L/C Draw, interest due on the Loans
or any Unreimbursed L/C Draws, and any Fees (other than the underwriting fee and
the administration fee paid to the Agent and the L/C Fronting Fee paid to the
L/C Issuer) or other amounts due under any of the Loan Documents, the Agent
shall distribute to each Lender that Lender's Ratable Share of the funds so
received except that funds received from the Borrower or another Loan Party to
reimburse the L/C Issuer for drawings on Letters of Credit (other than a
Lender's Ratable Share of such reimbursement payment to the extent such Lender
has complied fully with any funding obligations under Section 2.18(g) hereof) or
to fund any risk participant in the Letters of Credit or to pay the L/C Fronting
Fee shall be paid solely for the account of L/C Issuer. If the Agent fails to
distribute collected funds received by 2:00 P.M. on any Business Day by 3:00
P.M. of such Business Day or collected funds received after 2:00 P.M. on any
Business Day by 3:00 P.M. the next Business Day the funds shall bear interest
until distributed at the Federal Funds Effective Rate. The Agent agrees to make
its best efforts to provide telephonic notice to each Lender that it is in
receipt of funds from the Borrower and the day on which it will commence a wire
transfer of such Lender's share of such funds.
<PAGE>
 
        9.11. Holders of Notes. The Agent may deem and treat any
              ----------------
payee of any Note as the owner thereof for all purposes hereof unless and until
written notice of the assignment or transfer thereof shall have been filed with
the Agent. Any request, authority or consent of any Person who at the time of
making such request or giving such authority or consent is the holder of any
Note shall be conclusive and binding on any subsequent holder, transferee or
assignee of such Note or of any Note or Notes issued in exchange therefor.

        9.12. Equalization of Lenders. Each borrowing and each
              -----------------------                           
payment or prepayment by, or for the account of, the Borrower with respect to
principal, interest, Fees, or other amounts due from the Borrower hereunder to
the Lenders with respect to the Loans, shall (except as provided in Section
2.10, 2.12, 2.18(b) or 9.03 hereof) be made in proportion to the Loans
outstanding from each Lender or, if no such Loans are then outstanding, in
proportion to the Ratable Share of each Lender. Each payment of Unreimbursed L/C
Draws shall be made for the account of the L/C Issuer. The Lenders agree among
themselves that, with respect to all amounts received by any Lender (in its
capacity solely as a Lender) or any such holder for application on any
obligation hereunder or under any Note or under any such participation, whether
received by voluntary payment, by realization upon security, by the exercise of
the right of set-off or banker's lien, by counterclaim or by any other non-pro
rata source, equitable adjustment will be made in the manner stated in the
following sentence so that, in effect, all such excess amounts will be shared
ratably among the Lenders and such holders in proportion to their interest in
payments under the Notes, except as otherwise expressly provided herein. The
Lenders or any such holder receiving any such amount shall purchase for cash,
from each of the other Lenders, an interest in such Lender's Loans in such
amount as shall result in a ratable participation by the Lenders and each such
holder in the aggregate unpaid amount under the Notes, provided that if all or
any portion of such excess amount is thereafter recovered from the Lender or the
holder making such purchase, such purchase shall be rescinded and the purchase
price restored to the extent of such recovery, together with interest or other
amounts, if any, required by Law (including court order) to be paid by the
Lender or the holder making such purchase.

        9.13. Successor Agent. The Agent may resign as the Agent
              ---------------                                     
upon sixty (60) days' written notice to the Lenders and the Borrower. If such
notice shall be given, the Lenders shall appoint from among the Lenders a
successor agent for the Lenders, during such 60-day period, which successor
agent shall be reasonably satisfactory to the Borrower, to serve as agent
hereunder and under the several documents, the forms of which are attached
hereto as exhibits, or which are referred to herein. If at the end of such 60-
day period the Lenders have not appointed such a successor, the Agent shall
procure a successor reasonably satisfactory to the Lenders and the Borrower, to
serve as agent for the Lenders hereunder and under the several documents, the
forms of which are attached hereto as exhibits, or which are referred to herein.
Any such successor agent shall succeed to the rights, powers and duties of the
Agent. Upon the appointment of such successor agent or upon the expiration of
such 60-day period (or any longer period to which the Agent has agreed), the
former Agent's rights, powers and duties as Agent shall be terminated, without
any other or further act or deed on the part of such former Agent or any of the
parties to this Agreement. After any retiring Agent's resignation hereunder as
the Agent, the provisions of this Article IX shall inure to the benefit of such
retiring Agent as to any actions taken or omitted to be taken by it while it was
the Agent under this Agreement.
<PAGE>
 
        9.14. Calculations. In the absence of gross negligence or
              ------------                                         
willful misconduct, the Agent shall not be liable for any error in computing the
amount payable to any Lender whether in respect of the Loans, fees or any other
amounts due to the Lenders or the L/C Issuer under this Agreement. In the event
an error in computing any amount payable to any Lender or the L/C Issuer is
made, the Agent, the Borrower and each affected Person shall, forthwith upon
discovery of such error, make such adjustments as shall be required to correct
such error, and any compensation therefor will be calculated at the Federal
Funds Effective Rate.

        9.15.  Beneficiaries. Except as expressly provided herein,
               -------------                                        
the provisions of this Article IX are solely for the benefit of the Agent, the
Lenders and the L/C Issuer, and the Borrower shall not have any rights to rely
on or enforce any of the provisions hereof. In performing its functions and
duties under this Agreement, the Agent shall act solely as agent of the Lenders
and does not assume and shall not be deemed to have assumed any obligation
toward or relationship of agency or trust with or for the Borrower.

                                   ARTICLE X
                               GENERAL PROVISIONS
                               ------------------

        10.01. Amendments and Waivers. The Required Lenders, or the
               ----------------------                                
Agent with the consent in writing of the Required Lenders, and the Borrower may,
subject to the provisions of this Section 10.01, from time to time enter into
written supplemental agreements to this Agreement and the other Loan Documents
for the purpose of adding or deleting any provisions or otherwise changing,
varying or waiving in any manner the rights of the Lenders, the Agent or the
obligor thereunder or the conditions, provisions or terms thereof or waiving any
Event of Default thereunder or consenting to an action of any of the Borrower or
any of its Subsidiaries, but only to the extent specified in such written
agreements; provided, however, that no such supplemental agreement shall,
without the consent of all the Lenders:

              (a) waive an Event of Default by the Borrower in any payment of
principal, interest, Fees or other amounts due hereunder and under any of the
other Loan Documents, or otherwise postpone any scheduled payment date of any of
the foregoing;

              (b) reduce the interest rate relating to the Loans or change the
definition of the terms Base Rate, Prime Rate, Applicable Euro-Rate Margin,
Euro-Rate, Euro-Rate Interest Period, Euro-Rate Reserve Percentage or Federal
Funds Effective Rate so as to decrease the interest rate relating to the Loans;

              (c) change the Expiration Date;

              (d) reduce any Fee due the Lenders;

              (e) increase the maximum principal amount of either Revolving
Credit Commitment of any Lender, or increase the maximum Stated Amount of
Letters of Credit which may be issued and outstanding under the terms hereof;

              (f) change the definition of the term Required Lenders;
<PAGE>
 
              (g) release any Subsidiary Guarantor or any collateral; or

              (h) amend or waive the provisions of this Section 10.01.

Any such supplemental agreement shall apply equally to each of the Lenders and
the L/C Issuer and shall be binding upon the Borrower, the Lenders, the Agent,
all future holders of the Notes and all Participants. In the case of any waiver,
the Borrower, the Lenders, the L/C Issuer, the Agent shall be restored to its
former position and rights, and any Event of Default waived shall be deemed to
be cured and not continuing, but no such waiver shall extend to any subsequent
or other Event of Default, or impair any right consequent thereon.

        10.02. Taxes. The Borrower shall pay any and all stamp,
               -----                                             
document, transfer and recording taxes, filing fees and similar impositions
payable or hereafter determined by the Agent, the Lenders or the L/C Issuer to
be payable in connection with this Agreement, the other Loan Documents and any
other documents, instruments and transactions pursuant to or in connection with
any of the Loan Documents. The Borrower agrees to save the Agent, the Lenders
and the L/C Issuer harmless from and against any and all present and future
claims or liabilities with respect to, or resulting from, any delay in paying or
failure to pay any such taxes or similar impositions other than resulting from
the gross negligence or willful misconduct of the Agent, the Lenders or the L/C
Issuer.

        10.03.  Costs and Expenses, etc.
                -----------------------   

                (a) The Borrower shall:

                    (i) pay or reimburse the Agent for all reasonable out-of-
pocket costs and expenses incurred by the Agent in connection with (A) the
preparation, negotiation and execution of this Agreement, any other Loan
Documents or any instrument or document prepared in connection herewith or
therewith; (B) the completion of the Agent's "due diligence" permitted as a
condition of the closing; (C) the syndication efforts of the Agent with respect
to this Agreement and the commitments hereunder; and (D) the consummation of the
transactions contemplated hereby and thereby (including, without limitation, in
each case the reasonable fees and out-of-pocket expenses of the counsel to the
Agent as agreed in the Agent's Letter); and

                    (ii) reimburse the Agent, the L/C Issuer and each Lender on
demand for all reasonable out-of-pocket costs and expenses incurred by the
Agent, the L/C Issuer or such Lender in connection with the enforcement of or
preservation of any of its Liens, rights, powers, interests or remedies under
this Agreement or any other Loan Document (including, without limitation, in
each case the reasonable fees and out-of-pocket expenses of the respective
counsel to the Agent, the L/C Issuer and each Lender).

              (b) All of such costs, expenses and indemnities shall be payable
by the Borrower to the Agent, the Lenders or the L/C Issuer as appropriate upon
demand or as otherwise agreed upon by the Agent, the Lenders or the L/C Issuer
as appropriate and the Borrower, and shall constitute Lender Obligations under
this Agreement.

        10.04. Notices.
               -------   
<PAGE>
 
              (a) Notice to the Borrower. All notices required to be delivered
                  ----------------------
to the Borrower pursuant to this Agreement shall be in writing and shall be sent
to the following address, by hand delivery, recognized national overnight
courier service with all charges prepaid, telex, telegram, telecopier or by
United States certified mail, postage prepaid:

                  Mastech Corporation
                  1004 McKee Road
                  Oakdale, Pennsylvania  15071
                  Attention:    Vice President Finance
                  Telephone:    (412) 490-9349
                  Telecopier:   (412) 787-9225

              (b) Notice to the Agent. All notices required to be delivered to
                  -------------------
the Agent pursuant to this Agreement shall be in writing and shall be sent to
the following address, by hand delivery, recognized national overnight courier
service with all charges prepaid, telex, telegram, telecopier or by United
States certified mail, postage prepaid:

                  PNC Bank, National Association
                  Vice President
                  Telephone:   412-762-3627
                  Telecopier:  412-762-8672

              (c) Notice to L/C Issuer. All notices required to be sent to the
                  --------------------
L/C Issuer pursuant to this Agreement shall be in writing and shall be sent to
the following address by hand delivery, recognized national overnight courier
service with all charges prepaid, telex, telegram, telecopier or by United
States certified mail, postage prepaid:

              PNC Bank, National Association
              Multibank Loan Administration
              One PNC Plaza, 22nd Floor
              249 Fifth Avenue
              Pittsburgh, Pennsylvania 15222-2707
              Attention:   Arlene M. Ohler
              Vice President
              Telephone:   412-762-3627
              Telecopier:  412-762-8672

              (d) Notice to Lenders. All notices required to be sent to the
                  -----------------
Lenders pursuant to this Agreement shall be in writing and shall be sent to the
notice address of each Lender as set forth on Schedule 1.01 (a) hereto or such
                                              ----------------- 
Lender's signature page to the Assignment and Assumption Agreement executed by
it as a Purchasing Lender, as the case may be, by hand delivery, overnight
courier service with all charges prepaid, telex, telegram,
<PAGE>
 
telecopier or other means of electronic data communication or by the United
States mail, first class postage prepaid. All such notices shall be effective
three days after mailing, the date of telecopy transmission or when received,
whichever is earlier. The Borrower, the Lenders, the L/C Issuer and the Agent
may each change the address for service of notice upon it by a notice in writing
to the other parties hereto.


       10.05. Participation and Assignment.
              ---------------------------- 

              (a)  Sale of Participation.
                   --------------------- 

                   (i) Any Lender may, in the ordinary course of its commercial
lending business and in accordance with applicable law, and without the consent
of the Borrower, at any time sell to one or more Participants (which
Participants may be Affiliates of such Lender) Participations in the Revolving
Credit Commitment of such Lender or any Loan, the Note, or other interest of
such Lender hereunder. In the event of any such sale of a Participation, such
Lender's obligations under this Agreement to the Borrower shall remain
unchanged, such Lender shall remain solely responsible for its performance under
this Agreement, such Lender shall remain the holder of the Note made payable to
it for all purposes under this Agreement (including all voting rights hereunder)
and the Borrower shall continue to deal solely and directly with such Lender in
connection with such Lender's rights and obligations under this Agreement and
the other Loan Documents.

                    (ii) As between a Participant and that Participant's selling
Lender only, the sole issues on which the Participant shall have a contractual
right to vote are: (A) an increase in such Lender's Revolving Credit Commitment,
(B) any change of the term Base Rate, Euro-Rate, Euro-Rate Reserve Percentage,
or Applicable Euro-Rate Margin so as to decrease the interest rate relating to
the Loans, (C) extension of the term of either Revolving Credit Commitment, or
(D) postponement of the scheduled payment of principal, interest or Fees due
under any of the Loan Documents.

              (b) Assignments. Subject to the remaining provisions of this
                  ------------
Section 10.05(b), any Lender may at any time, in the ordinary course of its
commercial lending business, in accordance with applicable law, sell to one or
more Purchasing Lenders (which Purchasing Lender may be affiliates of the
Transferor Lender), all or a portion of its rights and obligations under this
Agreement and the Note then held by it, pursuant to an Assignment and Assumption
Agreement substantially in the form of Exhibit "G" and satisfactory to
                                       -----------
the Agent, executed by the Transferor Lender, such Purchasing Lender, the Agent
and the Borrower; subject, however to the following requirements:

                  (i) The Agent and the Borrower must each give its prior
consent to any such assignment which consent shall not be unreasonably withheld;
it being agreed that it shall not be deemed unreasonable for the Borrower to
decline to consent to such assignment if (A) such assignment would result in
incurrence of additional costs to the Borrower under Section 2.10, 2.11 or 2.12,
or (B) the proposed assignee has not provided to the Borrower any tax forms
received under Section 10.05(d); provided, however, no consent is required for
                                 --------  -------
the transfer by a Lender to its Affiliate so long as the conditions in clauses
(A) and (B) immediately above are satisfied;
<PAGE>
 
                  (ii) Each such assignment must be in a minimum amount of
$5,000,000, or, if in excess of $5,000,000, in integral multiples of $1,000,000;

                  (iii) each such assignment shall be of a constant, and not a
varying, percentage of the Transferor Lender's Revolving Credit Commitment,
outstanding Loans and all other rights and obligations under this Agreement and
the other Loan Documents; and

                  (iv) The Transferor Lender shall pay to the Agent, for its own
Account, a fee of $3,500 for each such assignment (the "Assignment Fee").

Upon the execution, delivery, acceptance and recording of any such Assignment
and Assumption Agreement, from and after the Transfer Effective Date determined
pursuant to such Assignment and Assumption Agreement, (i) the Purchasing Lender
thereunder shall be a party hereto as a Lender and, to the extent provided in
such Assignment and Assumption Agreement, shall have the rights and obligations
of a Lender hereunder with a Revolving Credit Commitment as set forth therein,
and (ii) the Transferor Lender thereunder shall, to the extent provided in such
Assignment and Assumption Agreement, be released from its obligations under this
Agreement as a Lender. Such Assignment and Assumption Agreement shall be deemed
to amend this Agreement to the extent, and only to the extent, necessary to
reflect the addition of such Purchasing Lender as a Lender and the resulting
adjustment of Ratable Share arising from the purchase by such Purchasing Lender
of all or a portion of the rights and obligations of such Transferor Lender
under this Agreement and the Notes. On or prior to the Transfer Effective Date,
the Borrower shall execute and deliver to the Agent, in exchange for the
surrendered Note held by the Transferor Lender, a new Note to the order of such
Purchasing Lender in an amount equal to the Revolving Credit Commitment assumed
by it and purchased by it pursuant to such Assignment and Assumption Agreement,
and a Note to the order of the Transferor Lender in an amount equal to the
Revolving Credit Commitment retained by it hereunder.

              (c) Assignment Register. The Agent shall maintain at its address
                  -------------------
referred to in Section 10.04(b) a copy of each Assignment and Assumption
Agreement delivered to it and a register (the "Register") for the recordation of
the names and addresses of the Lenders and the amount of the Loans owing to each
Lender from time to time. The entries in the Register shall be conclusive, in
the absence of manifest error, and the Borrower, the Agent, the Lender and the
L/C Issuer may treat each Person whose name is recorded in the Register as the
owner of the Loans recorded therein for all purposes of this Agreement. The
Register shall be available at the office of the Agent for inspection by the
Borrower or any Lender at any reasonable time and from time to time upon
reasonable prior notice.

              (d) Withholding of Income Taxes. At least five (5) Business Days
                  ---------------------------
prior to the first date on which interest or fees are payable hereunder for the
account of any Purchasing Lender or Participant, each Purchasing Lender or
Participant that is not incorporated under the laws of the United States or a
state thereof shall deliver to the Borrower and the Transferor Lender two duly
completed copies of United
<PAGE>
 
States Internal Revenue Service Form W-9, 4224 or 1001 or other applicable form
prescribed by the Internal Revenue Service. Such form shall certify that such
Purchasing Lender or Participant is entitled to receive payments under this
Agreement and the Notes without deduction or withholding of any United States
Federal income taxes, or is subject to such tax at a reduced rate under an
applicable tax treaty or under United States Internal Revenue Service Form W-8,
or another applicable form or a certificate of such Purchasing Lender or
Participant indicating that no such exemption or reduced rate is allowable with
respect to such payments. Each Purchasing Lender or Participant which delivers a
Form W-8, W-9, 4224 or 1001 further undertakes to deliver to the Borrower and
its Transferor Lender two additional copies of such form (or a successor form)
on or before the date that such form expires or becomes obsolete or otherwise is
required to be resubmitted as a condition to obtaining an exemption from
withholding tax or after the occurrence of any event requiring a change in the
most recent form so delivered by it, and such amendments thereto or extensions
or renewals thereof as may be reasonably required by the Borrower or its
Transferor Lender, either certifying that such Purchasing Lender or Participant
is entitled to receive payments under this Agreement and the Notes without
deduction or withholding of any United States Federal income taxes or is subject
to such tax at a reduced rate under an applicable tax treaty or stating that no
such exemption or reduced rate is allowable. The Borrower, in the case of a
Purchasing Lender or Transferor Lender in the case of a Participant shall be
entitled to withhold United States Federal income taxes at the full withholding
rate, unless the Purchasing Lender or Participant as the case may be establishes
an exemption, or at the applicable reduced rate, as established pursuant to this
provisions of this Section 10.05(d).

              (e) Assignments to Federal Reserve Bank. In addition to the
                  ----------------------------------- 
assignments permitted above, any Lender may assign and pledge all or any portion
of its Loans and Notes to any Federal Reserve Bank as collateral security
pursuant to Regulation A of the Board of Governors of the Federal Reserve System
and any Operating Circular issued by such Federal Reserve Bank. No such
assignment shall release the assigning Lender from its obligations and duties
hereunder or under the other Loan Documents.

        10.06. Successors and Assigns. This Agreement shall be
               ----------------------                           
binding upon the Borrower and the Agent, the Lenders, the L/C Issuer and their
respective successors and assigns, and shall inure to the benefit of the
Borrower, the Agent, the Lenders, the L/C Issuer and respective successors and
assigns; provided, however, that the Borrower shall not assign its rights or
         --------  -------                                                  
duties hereunder or under any of the other Loan Documents without the prior
written consent of the Lenders.

        10.07. No Implied Waivers; Cumulative Remedies; Writing Required. No
               ---------------------------------------------------------
course of dealing and no delay or failure of the Agent or any Lender in
exercising any right, power, remedy or privilege under this Agreement or any
other Loan Document shall affect any other or future exercise thereof or operate
as a waiver thereof; nor shall any single or partial exercise thereof or any
abandonment or discontinuance of steps to enforce such a right, power, remedy or
privilege preclude any further exercise thereof or of any other right, power,
remedy or privilege. The rights and remedies of the Agent and the Lenders under
this Agreement and any other Loan Documents are cumulative and not exclusive of
any rights or remedies which they would otherwise have. Any waiver, permit,
consent or approval of any kind or character on the part of any Lender of any
breach or default under this Agreement or any such waiver of any provision or
condition of this Agreement must be in writing and shall be effective only to
the extent specifically set forth in such writing.
<PAGE>
 
        10.08.  Severability. Any provision of this Agreement which
                ------------                                         
is prohibited or unenforceable in any jurisdiction shall, as to such
jurisdiction, be ineffective to the extent of such prohibition or enforceability
without invalidating the remaining portions hereof or affecting the validity or
enforceability of such provision in any other jurisdiction.

        10.09. Indemnity. The Borrower hereby agrees to indemnify
               ---------                                           
the Agent, the Lenders, the L/C Issuer, and the directors, officers, employees,
attorneys, agents and Affiliates or all of the foregoing (each of the foregoing
an "Indemnified Person") against, and hold each of them harmless from, any loss,
liabilities, damages, claims, costs and expenses (including reasonable
attorneys' fees and disbursements) suffered or incurred by any Indemnified
Person (except those caused by such Indemnified Person's gross negligence or
willful misconduct, ) arising out of, resulting from or in any manner connected
with, the execution, delivery and performance of each of the Loan Documents, the
Lender Obligations and any and all transactions related to or consummated in
connection with the Lender Obligations, including, without limitation, losses,
liabilities, damages, claims, costs and expenses suffered or incurred by any
Indemnified Person arising out of or related to investigating, preparing for,
defending against, or providing evidence, producing documents or taking any
other action in respect of any commenced or threatened litigation,
administrative proceeding or investigation under any Federal securities law or
by any Official Body of any jurisdiction, or at common law or otherwise, that is
alleged to arise out of or is based on (i) any untrue statement or alleged
untrue statement of any material fact of the Borrower or any Affiliate of the
Borrower in any document or schedule filed with the Securities and Exchange
Commission or any other Official Body, (ii) any omission or alleged omission to
state any material fact required to be stated in such document or schedule, or
necessary to make the statements made therein, in light of the circumstances
under which made, not misleading; (iii) any actual or alleged acts, practices or
omissions of the Borrower, any other Loan Party, or any of their respective
directors, officers, partners, employees, attorneys, agents or Affiliates,
related to the making of any acquisition, purchase of shares or assets pursuant
thereto, financing of such purchases or the consummation of any other
transactions contemplated by any such acquisitions that are alleged to be in
violation of any Federal securities law or of any other statute, regulation or
other law of any jurisdiction applicable to the making of any such acquisition,
the purchase of shares or assets pursuant thereto, the financing of such
purchases or the consummation of the other transactions contemplated by any such
acquisition; or (iv) any withdrawals, termination or cancellation of any such
proposed acquisition for any reason whatsoever. The indemnity set forth in this
Section 10.09 shall be in addition to any other obligations or liabilities of
the Borrower to the Agent, the Lenders or the L/C Issuer, or at common law or
otherwise. The provisions of this Section 10.09 shall survive the payment of the
Lender Obligations and the termination of this Agreement and the other Loan
Documents.

        10.10  Confidentiality. The Agent, the Lenders and the L/C
               ---------------                                      
Issuer shall keep confidential and not disclose to any Person, other than to
their respective directors, officers, employees, Affiliates and agents, and to
actual and potential Purchasing Lenders and Participants, all non-public
information concerning the Borrower and the Borrower's Affiliates which comes
into the possession of the Agent, the Lenders or the L/C Issuer during the term
hereof. Notwithstanding the foregoing, the Agent, the Lenders and the L/C Issuer
may disclose information concerning the Borrower (i) in accordance-with normal
banking practices and the Agent's, such Lender's or the L/C Issuer's policies
concerning disclosure of such information in connection with syndication or
sales of Participations, subject to informing the recipient of such
<PAGE>
 
information of the duties of confidentiality hereunder, (ii) pursuant to what
the Agent, such Lender or the L/C Issuer believes to be the lawful requirements
or request of any Official Body regulating banks or banking, (iii) as required
by governmental regulation or rule, judicial process or subpoena; provided
however, if permitted by law, the Agent, or such Lender shall notify the
Borrower and permit the Borrower, at the Borrower's cost, to contest such
subpoena; and (iv) to their respective attorneys, accountants and auditors who
have been informed of the confidentiality hereunder.

        10.11. Survival. All representations, warranties, covenants
               --------                                              
and agreements of the Borrower contained herein or in the other Loan Documents
or made in writing in connection herewith shall survive the issuance of the
Notes and the Letters of Credit and shall continue in full force and effect so
long as the Borrower may borrow hereunder and so long thereafter until payment
in full of all the Notes and the Lender Obligations is made. The obligations of
the Borrower under Sections 2.13, 2.19, 2.21, 6.13, 10.02, 10.03 and 10.09 shall
survive the termination of this Agreement and the discharge of the other
obligations of the Borrower hereunder, and any other Loan Documents, and shall
also survive the payment in full of all Lender Obligations, the termination of
the Revolving Credit Commitment in accordance with the provisions of this
Agreement and the termination or expiration of all Letters of Credit in
accordance with their respective terms.

        10.12. GOVERNING LAW. THIS AGREEMENT AND THE OTHER LOAN DOCUMENTS SHALL
               -------------
BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE COMMONWEALTH OF
PENNSYLVANIA, WITHOUT REGARD TO THE PRINCIPLES THEREOF REGARDING CONFLICT OF
LAWS, EXCEPTING APPLICABLE FEDERAL LAW AND EXCEPT ONLY TO THE EXTENT PRECLUDED
BY THE MANDATORY APPLICATION OF THE LAW OF ANOTHER JURISDICTION.

        10.13. FORUM. THE PARTIES HERETO AGREE THAT ANY ACTION OR PROCEEDING
               -----
ARISING OUT OF OR RELATING TO THIS AGREEMENT OR THE OTHER LOAN DOCUMENTS TO
WHICH THE BORROWER IS A PARTY MAY BE COMMENCED IN THE COURT OF COMMON PLEAS OF
ALLEGHENY COUNTY, PENNSYLVANIA OR IN THE DISTRICT COURT OF THE UNITED STATES FOR
THE WESTERN DISTRICT OF PENNSYLVANIA, AND THE PARTIES HERETO AGREE THAT A
SUMMONS AND COMPLAINT COMMENCING AN ACTION OR PROCEEDING IN EITHER OF SUCH
COURTS SHALL BE PROPERLY SERVED AND SHALL CONFER PERSONAL JURISDICTION IF SERVED
PERSONALLY OR BY CERTIFIED MAIL TO THE PARTIES AT THEIR ADDRESSES SET FORTH IN
SECTION 10.04, OR AS OTHERWISE PROVIDED UNDER THE LAWS OF THE COMMONWEALTH OF
PENNSYLVANIA. FURTHER, THE BORROWER HEREBY SPECIFICALLY CONSENTS TO THE PERSONAL
JURISDICTION OF THE COURT OF COMMON PLEAS OF ALLEGHENY COUNTY, PENNSYLVANIA AND
THE DISTRICT COURT OF THE UNITED STATES FOR THE WESTERN DISTRICT OF PENNSYLVANIA
AND WAIVES AND HEREBY ACKNOWLEDGES THAT IT IS ESTOPPED FROM RAISING ANY
OBJECTION BASED ON FORUM NON CONVENIENS, ANY CLAIM THAT EITHER SUCH COURT LACKS
                   --------------------
PROPER VENUE OR ANY OBJECTION THAT EITHER SUCH COURT LACKS PERSONAL JURISDICTION
OVER THE BORROWER SO AS TO PROHIBIT EITHER SUCH COURT FROM ADJUDICATING ANY
ISSUES RAISED IN A COMPLAINT FILED WITH EITHER SUCH COURT AGAINST THE BORROWER
BY THE AGENT, THE LENDERS OR THE L/C ISSUER CONCERNING THIS AGREEMENT OR THE
OTHER LOAN
<PAGE>
 
DOCUMENTS OR PAYMENT TO THE LENDERS. THE BORROWER HEREBY ACKNOWLEDGES AND AGREES
THAT THE CHOICE OF FORUM CONTAINED IN THIS SECTION 10.13 SHALL NOT BE DEEMED TO
PRECLUDE THE ENFORCEMENT OF ANY JUDGMENT OBTAINED IN ANY FORUM OR THE TAKING OF
ANY ACTION UNDER THE LOAN DOCUMENTS TO ENFORCE THE SAME IN ANY APPROPRIATE
JURISDICTION.

        10.14. Non-Business Days.  Whenever any payment hereunder or
               -----------------                                    
under the Notes is due and payable on a day which is not a Business Day, such
payment may be made on the next succeeding Business Day, and such extension of
time shall in each such case be included in computing interest in connection
with such payment.

        10.15. Integration. This Agreement and the other Loan
               -----------                                     
Documents constitute the entire agreement between the parties relating to this
financing transaction and they supersede all prior understandings and
agreements, whether written or oral, between the parties hereto relating to the
transactions provided for herein.

        10.16. Counterparts. This Agreement and any amendment hereto
               ------------                                           
may be executed in several counterparts and by each party on a separate
counterpart, each of which, when so executed and delivered, shall be an
original, but all of which together shall constitute but one and the same
instrument. In proving this Agreement, it shall not be necessary to produce or
account for more than one such counterpart signed by the other party against
whom enforcement is sought. Delivery of an executed counterpart of a signature
page to this Agreement by telecopier shall be as effective as delivery of a
manually executed counterpart of this Agreement.

        10.17. Funding by Branch, Subsidiary or Affiliate.
               ------------------------------------------ 

              (a) Notional Funding. Each Lender shall have the right from time
                  ---------------- 
to time, without notice to the Borrower, to deem any branch, subsidiary or
affiliate (which for the purposes of this Section 10.17 shall mean any
corporation or association which is directly or indirectly controlled by or is
under direct or indirect common control with any corporation or association
which directly or indirectly controls such Lender) of such Lender to have made,
maintained or funded any Loan in Dollars or in any Optional Currency to which
the Euro-Rate Option applies at any time, provided that immediately following
(on the assumption that a payment were then due from the Borrower to such other
office) and as a result of such change the Borrower would not be under any
greater financial obligation to such Lender hereunder, pursuant to Section 2.08,
2.10, 2.11 or 2.12 hereof than it would have been in the absence of such change.
Notional funding offices may be selected by each Lender without regard to a
Lender's actual methods of making, maintaining or funding the Loans or any
sources of funding actually used by or available to such Lender.

              (b) Actual Funding. Each Lender shall have the right from time to
                  --------------
time to make or maintain any Loan by arranging for a branch, subsidiary or
affiliate of such Lender to make or maintain such Loan subject to the last
sentence of this Section 10.17(b). If any Lender causes a branch, subsidiary or
affiliate to make or maintain any part of the Loans hereunder, all terms and
conditions of this Agreement shall, except where the context clearly requires
otherwise, be applicable to such part of the Loans to the same extent as if such
Loans were made or maintained by such Lender but in no event shall any Lender's
use of such a branch,
<PAGE>
 
subsidiary or affiliate to make or maintain any part of the Loans hereunder
cause such Lender or such branch, subsidiary or affiliate to incur any cost or
expenses payable by the Borrower hereunder or require the Borrower to pay any
other compensation to any such Lender (including, without limitation, any
expenses incurred or payable pursuant to Section 2.08, 2.10, 2.11 or 2.12
hereof) which would otherwise not be incurred.

        10.18 WAIVER OF JURY TRIAL. THE BORROWER, EACH LENDER, THE AGENT AND THE
              --------------------
L/C ISSUER EACH HEREBY WAIVES THE RIGHT TO TRIAL BY JURY IN ANY COURT AND IN ANY
ACTION OR PROCEEDING OF ANY TYPE IN WHICH THE BORROWER, THE LENDERS, THE AGENT,
THE L/C ISSUER OR ANY OF THEIR RESPECTIVE SUCCESSORS OR ASSIGNS IS A PARTY, AS
TO ALL MATTERS AND THINGS ARISING OUT OF THIS AGREEMENT, THE NOTES OR THE OTHER
LOAN DOCUMENTS.



                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]
<PAGE>
 
  IN WITNESS WHEREOF, the parties hereto, intending to be legally bound hereby,
have caused this Credit Agreement to be executed by their respective duly
authorized officers as of the date first written above.

                                          MASTECH CORPORATION, a Pennsylvania
                                          corporation


                                          By:                            (SEAL)
                                             ----------------------------
                                          Name:
                                          Title: 


                                          PNC BANK, NATIONAL ASSOCIATION,
                                          in its capacities as Agent and L/C
                                          Issuer and as a Lender


                                          By:                            (SEAL)
                                             ----------------------------
                                          Name:
                                          Title: 



                                          FLEET NATIONAL BANK


                                          By:                            (SEAL)
                                             ----------------------------
                                          Name:
                                          Title: 


                                          FIRST UNION NATIONAL BANK


                                          By:                            (SEAL)
                                             ----------------------------
                                          Name:
                                          Title: 


                                          CHASE MANHATTAN BANK


                                          By:                            (SEAL)
                                             ----------------------------
                                          Name:
                                          Title: