EXHIBIT 4.9

                                 THIRD AMENDMENT

         THIRD AMENDMENT (this "Third Amendment"),  dated as of October 8, 1999,
to the Credit  Agreement,  dated as of March 4, 1997,  as modified by the Waiver
and First  Amendment  dated as of  November  25,  1997,  the Waiver  dated as of
February 11, 1998, the Waiver and Second  Amendment dated as of May 27, 1998 and
the Waiver  dated as of November  13, 1998 (as the same may be further  amended,
supplemented or otherwise  modified from time to time, the "Credit  Agreement"),
among  PACKARD  BIOSCIENCE  COMPANY,  a Delaware  corporation  ("Packard"),  the
Subsidiary  Borrowers  party  thereto,  the  lenders  from time to time  parties
thereto (the  "Lenders"),  BANC OF AMERICA  SECURITIES  LLC  (formerly  known as
NATIONSBANC  MONTGOMERY  SECURITIES LLC) and CIBC  OPPENHEIMER  CORP.  (formerly
known as CIBC-WOOD GUNDY SECURITIES  CORP.), as co-arrangers and  co-syndication
agents (in such capacities, the "Co-Arrangers" and the "Co-Syndication Agents"),
CANADIAN  IMPERIAL BANK OF COMMERCE,  as documentation  agent (in such capacity,
the "Documentation Agent"), and BANK OF AMERICA, N.A. (formerly known as BANK OF
AMERICA NATIONAL TRUST AND SAVINGS ASSOCIATION), as administrative agent.

                              W I T N E S S E T H :

         WHEREAS,  Packard has  requested  that the  Lenders  agree to amend the
Credit  Agreement upon the terms and subject to the conditions set forth herein;
and

         WHEREAS,  the Lenders have agreed to such amendment only upon the terms
and subject to the conditions set forth herein;

         NOW,  THEREFORE,  in  consideration  of the  premises  and  the  mutual
covenants contained herein, the parties hereto hereby agree as follows:

         1. Defined Terms.  Capitalized  terms not otherwise defined herein have
the meanings ascribed to such terms in the Credit Agreement.

         2. Section  1.1--Consolidated  EBITDA.  The definition of  Consolidated
EBITDA  contained in Section 1.1 of the Credit  Agreement  is hereby  amended by
adding the following new clause (g) immediately after clause (f) thereof:

               "and (g) up to $2,000,000 of professional fees paid in connection
          with the Foreign Subsidiary Corporate Reorganization"

         3. Section  1.1--Consolidated  Interest  Expense.   The  definition  of
Consolidated  Interest Expense  contained in Section 1.1 of the Credit Agreement
is  hereby  amended  by adding  the words ", but  excluding  the  Amendment  Fee
referred to in the Third Amendment hereto" at the end of the last  parenthetical
contained therein.

         4. Section 1.1--Consolidated Total Debt. The definition of Consolidated
Total Debt  contained in Section 1.1 of the Credit  Agreement is hereby  amended
and restated in its entirety as follows:

               "Consolidated  Total Debt": at any date, the aggregate  principal
          amount of all  Indebtedness  of Packard and its  Subsidiaries  at such
          date (other than the principal  amount of the Japan Debt to the extent
          Packard  Japan  KK has  an  equivalent  amount  of  cash  ("Equivalent
          Japanese  Cash") on hand on such date),  determined on a  consolidated
          basis in accordance with GAAP; provided, that, except for calculations
          of the Consolidated  Leverage Ratio pursuant to the Pricing Grid, such
          amount shall be reduced by the aggregate amount of cash on hand (other
          than  Equivalent  Japanese  Cash) held by the  Borrower  or any of its
          Subsidiaries (not to exceed $8,000,000).

         5. Section  1.1--Fronted  Offshore Revolving Credit Loan Sublimit.  The
definition  of Fronted  Offshore  Revolving  Credit Loan  Sublimit  contained in
Section 1.1 of the Credit  Agreement  is hereby  amended by changing  the amount
"$35,000,000" to the amount "$50,000,000".

         6. Section 1.1--New Definition.  Section 1.1 of the Credit Agreement is
hereby  amended  by adding  the  following  new  definition  in the  appropriate
alphabetical order:

               "Foreign  Subsidiary  Corporate   Reorganization":   a  corporate
          reorganization   pursuant  to  which  certain  of  Packard's   Foreign
          Subsidiaries  shall  become  Subsidiaries  of one or more Wholly Owned
          Subsidiaries organized under the laws of countries that are members of
          the European Union or the laws of  Switzerland.  Packard hereby agrees
          to give the  Administrative  Agent at least 30 days' advance notice of
          the Foreign Subsidiary Corporate Reorganization, which notice shall be
          accompanied  by  a  substantially  final  description,  in  reasonable
          detail, of such reorganization.

         7. Section  8.9(d).  Section  8.9(d) of the Credit  Agreement is hereby
amended by  changing  the phrase  "Packard  or any of its  Subsidiaries"  (which
appears  twice in said  Section) to the phrase  "Packard or any of its  Domestic
Subsidiaries".

         8. Section  9.1(a).  The third,  fourth and fifth rows of the table set
forth in Section  9.1(a) are hereby  amended and  restated in their  entirety as
follows:

               December 31, 1998 - September 29, 1999         5.50:1.00
               September 30, 1999 - December 30, 1999         5.85:1.00
               December 31, 1999 - June 29, 2000              5.35:1.00
               June 30, 2000 - December 30, 2000              5.15:1.00
               December 31, 2000 - March 30, 2001             4.80:1.00
               March 31, 2001 - December 30, 2001             4.50:1.00

         9. Section  9.1(c).  The  first row of the table  set forth in  Section
9.1(c) is hereby amended and restated in its entirety as follows:

               June 30, 1997 - September 29, 1999             1.00:1.00
               September 30, 1999 - December 30, 1999         0.90:1.00
               December 31, 1999 - March 30, 2000             1.00:1.00

         10. Section 9.2 (d).  Section 9.2(d) of the  Credit Agreement is hereby
amended and restated in its entirety as follows:

               "(d)  Indebtedness  of any Wholly  Owned  Foreign  Subsidiary  to
          Packard or any  Wholly  Owned  Subsidiary  Guarantor  in an  aggregate
          amount not to exceed $25,000,000 at any one time outstanding, provided
          that (i) such  Indebtedness  is evidenced by a note that is pledged as
          collateral under the Guarantee and Collateral Agreement,  (ii) no more
          than $5,000,000 of such  Indebtedness  shall result from cash loans to
          any such Foreign  Subsidiary (with any such Indebtedness not resulting
          from cash loans being  referred to herein as "Non-Cash  Indebtedness")
          and (iii) in the case of any such  Indebtedness  issued in  connection
          with a transfer of property (other than cash) to a Foreign Subsidiary,
          such transfer constitutes a Disposition expressly permitted by Section
          9.5;"


         11. Section 9.6.

          (a) Section 9.6 of the Credit  Agreement is hereby amended by changing
the amount "$2,000,000" to the amount "$5,000,000".

          (b) Section 9.6 of the Credit  Agreement  is hereby  amended by adding
the following new clause (C) to the end thereof:


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               "and (C)  Packard  may  make  cash  payments  in  respect  of tax
          obligations  of  employees  or  directors  of  Packard  or  any of its
          Subsidiaries resulting from the exercise by such Persons of options to
          purchase  common  stock of Packard  in  exchange  for a  corresponding
          reduction in the number of shares obtainable upon such exercise"


         12. Section 9.7.  Section 9.7 of the Credit Agreement is hereby amended
by  changing  the  amounts   "$10,000,000"   and  "$3,000,000"  to  the  amounts
"$15,000,000" and "$5,000,000", respectively.

         13. Section 9.8(f).  Section 9.8(f) of the Credit  Agreement  is hereby
amended and restated in its entirety as follows:

               "(f) (i)  investments  by Packard or any of its  Subsidiaries  in
          Packard  or any Person  that,  prior to such  investment,  is a Wholly
          Owned  Subsidiary  Guarantor,   (ii)  any  investment  resulting  from
          intercompany  reorganizations  to the extent  expressly  permitted  by
          Section  9.5(d)  or (e) and (iii) any  investment  resulting  from the
          issuance of Non-Cash Indebtedness (as defined in Section 9.2(d));"


         14. Section 9.8(g).

          (a) The  second  parenthetical  contained  in  Section  9.8(g) of  the
Credit Agreement is hereby amended and restated in its entirety as follows:

               "(or,  (x) in the  case  of  investments  in  CCS  Packard  Inc.,
          $27,000,000  and (y) in the case of one other  investment  during  the
          term of this Agreement, $40,000,000)"

          (b) Clause (ii) of  the  proviso  to   Section  9.8(g) of  the  Credit
Agreement is hereby amended by changing the amount  "$20,000,000"  to the amount
"$23,000,000".

          15. Section 9.9(b).  Section 9.9(b) of the Credit  Agreement is hereby
amended by changing the amount "$2,000,000" to the amount "$5,000,000".

         16.  Standby  Letters  of Credit in  Offshore  Currencies.  The  Credit
Agreement is hereby amended to the extent necessary to permit standby Letters of
Credit in  Offshore  Currencies  ("Offshore  Letters of Credit") to be issued on
terms and conditions  comparable to those  applicable to Letters of Credit under
the Credit Agreement and, to the extent relevant, the Fronted Offshore Revolving
Credit  Subfacility.  Without  limiting the  generality  of the  foregoing,  the
following  terms and  conditions  shall be  applicable  to  Offshore  Letters of
Credit:  (1)  the  account  party  must be a  Borrower  (and,  accordingly,  all
obligations  of the type  applicable  to Packard  under  Section 3 of the Credit
Agreement  shall, in the case of Offshore  Letters of Credit,  be obligations of
such Borrower),  (2) each L/C Participant  will be obligated to make payments to
the  Issuing  Lender in respect of  Offshore  Letters of Credit in the  relevant
Offshore  Currency  (or, at the option of the Issuing  Lender,  in Dollars based
upon the Dollar Equivalent of the relevant  Reimbursement  Obligation) under the
circumstances  described in Section 3.4 of the Credit Agreement,  (3) the limits
described  in clauses  (a),  (b) and (c) of Section 4.1 of the Credit  Agreement
shall apply to each issuance of an Offshore Letter of Credit, (4) the procedures
specified in Section 4.5 of the Credit  Agreement  shall apply to each  Offshore
Currency  utilized for the Offshore  Letters of Credit,  (5) Offshore Letters of
Credit shall count as  utilization  of the  Revolving  Credit  Commitments,  the
Fronted Offshore Revolving Credit Sublimit and the L/C Commitment (determined on
the basis of the Dollar Equivalent thereof),  including, without limitation, for
the  purposes  of Section  5.4(g) of the Credit  Agreement,  (6)  references  to
Fronted Offshore Revolving Credit Loans shall, to the extent relevant, be deemed
to include the L/C Obligations in respect of Offshore  Letters of Credit for the
purposes of interpreting  provisions  relating to the administration of Offshore
Currency matters, including, without limitation, (I) the definitions of "Banking
Day",  "Calculation  Date" and "Cost of Funds" and (II)  Section  5.10(e) of the
Credit Agreement,  (7) relevant determinations to be made by the Fronting Lender
in respect of Offshore  Currency  matters shall, in the case of Offshore Letters
of Credit, be made by the Issuing Lender, (8) the Offshore  Currencies for which
Offshore  Letters of Credit are  available,  as well as  administrative  matters
relating  to  Offshore  Letters of Credit,  shall be  determined  pursuant  to a
separate agreement between the Issuing Lender and the relevant Borrowers.

         17.  Release of Liens.  The  parties  hereto (a)  acknowledge  that the
Foreign Subsidiary Corporate Reorganization may result in certain direct Foreign
Subsidiaries of the Loan Parties becoming  indirect Foreign  Subsidiaries of the
Loan  Parties and (b) confirm the  authority  of the  Administrative  Agent,  as
provided in Section 11.10 of the Credit  Agreement,  to release any Liens on the
Capital Stock of such formerly direct Foreign  Subsidiaries  created pursuant to
the Security Documents.

         18.  Conditions to  Effectiveness.  This Third  Amendment  shall become
effective (the actual date of such effectiveness, the "Third Amendment Effective
Date") as of the date first above  written  when (a)  counterparts  hereof shall
have been duly executed and delivered by the Required  Lenders,  Packard and the
Administrative  Agent and  acknowledged  by each  Subsidiary  Guarantor  and (b)
Packard  shall have paid to the  Administrative  Agent for  distribution  to the
relevant  Lenders an amendment fee (the  "Amendment  Fee") equal to 0.25% of the
sum of the Revolving  Credit  Commitment  and Term Loans of each Lender that has
submitted an executed signature page to this Amendment by facsimile transmission
to the  Administrative  Agent or its counsel prior to 12:00 Noon,  New York City
time, on October 8, 1999.

         19. Representations.  Packard represents and warrants that:

          (a) this  Third  Amendment  has been  duly  authorized,  executed  and
delivered by Packard;

          (b) each of this Third Amendment,  and the Credit Agreement as amended
by  this  Third   Amendment,    constitutes  the  legal,   valid   and   binding
obligation of Packard;

          (c) each  of  the   representations  and   warranties  set   forth  in
Section 6 of the Credit Agreement are true and correct as of the Third Amendment
Effective  Date;  provided  that  references  in the  Credit  Agreement  to this
"Agreement"  shall be deemed  references  to the Credit  Agreement as amended by
this Third Amendment; and

          (d) after giving effect to this Third Amendment,  there does not exist
any Default or Event of Default.

         20.  Continuing  Effect.  Except as expressly amended or waived hereby,
the Credit  Agreement  shall  continue to be and shall  remain in full force and
effect in accordance with its terms.

         21.  Expenses.  Packard agrees to pay and reimburse the  Administrative
Agent for all of its  out-of-pocket  costs and expenses  incurred in  connection
with  the  negotiation,  preparation,  execution,  and  delivery  of this  Third
Amendment,  including  the  reasonable  fees  and  expenses  of  counsel  to the
Administrative Agent.

         22.  Counterparts.  This Third  Amendment may be executed on any number
of separate  counterparts and all of said counterparts taken  together  shall be
deemed to constitute one and the same instrument.

         23.  GOVERNING  LAW.  THIS THIRD  AMENDMENT  SHALL  BE GOVERNED BY, AND
CONSTRUED AND INTERPRETED IN ACCORDANCE  WITH, THE LAW OF THE STATE OF NEW YORK.

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



PACKARD BIOSCIENCE COMPANY

By:
Name:
Title:



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                           ACKNOWLEDGEMENT AND CONSENT

                  Each of the undersigned does hereby acknowledge and consent to
the foregoing Third  Amendment.  Each of the undersigned does hereby confirm and
agree that,  after giving  effect to such Third  Amendment,  the  Guarantee  and
Collateral   Agreement  and  the  other  Security  Documents  in  favor  of  the
Administrative Agent to which it is a party are and shall continue to be in full
force and effect and are hereby confirmed and ratified in all respects.


                                            PACKARD INSTRUMENT COMPANY, INC.

                                            By:
                                            Name:
                                            Title:


                                            AQUILA TECHNOLOGIES GROUP, INC.

                                            By:
                                            Name:
                                            Title:


                                            CCS PACKARD, INC.

                                            By:
                                            Name:
                                            Title:


                                            HARWELL INSTRUMENTS LIMITED

                                            By:
                                            Name:
                                            Title:


                                            TENNELEC, INC.

                                            By:
                                            Name:
                                            Title:



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