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                                                             Exhibit 10(iii)A(3)



                               AMENDMENT NO. 2 TO
                        NATIONAL SERVICE INDUSTRIES, INC.
                            BENEFITS PROTECTION TRUST

     This  Amendment  made and  entered  into as of this 23rd day of  September,
1997, by and between National Service Industries,  Inc., a Delaware  Corporation
(the  "Company"),  and Wachovia  Bank,  N.A.  (formerly  Wachovia Bank and Trust
Company), as Trustee (the "Trustee");

                              W I T N E S S E T H:

     WHEREAS,  the Company  previously  established a trust arrangement known as
the National Service Industries, Inc. Benefits Protection Trust (the "Trust") in
order to  ensure  that,  in the  event of  Change  in  Control  of the  Company,
participants and their beneficiaries  receive the benefits which the Company and
its  Affiliates  are  obligated  to  provide   pursuant  to  various   executive
compensation arrangements (collectively, the "Plans"); and

     WHEREAS,  the  Company  now  desires  to amend  the  Trust  in a number  of
respects;

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

                                       1.

          Section 2.2 is hereby  amended by adding the  following  new  sentence
after the first sentence of the present section:

          "The Trust shall become irrevocable upon the occurrence of a Change in
     Control, subject to the provisions of Section 17.5."

                                       2.

          Section 4.2 is hereby amended by deleting the second paragraph of such
section in its entirety and substituting the following in lieu thereof:

     "Immediately  upon the  occurrence of a Threatened  Change in Control and a
     Change in Control,  the Company  shall  contribute  sufficient  cash to the
     Benefit Account to pay all benefits earned or accrued as of the date of the
     Threatened  Change in Control  and the Change in Control  (whether  payable
     currently or on a deferred  basis) under all the Plans as determined by the
     Trustee in its discretion."





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                                                             Exhibit 10(iii)A(3)
                                       3.

     Section  4.3 is hereby  amended  by  deleting  the  present  section in its
entirety and substituting the following in lieu thereof:

     "During a Threatened  Change in Control Period or after the occurrence of a
     Change in Control,  if the Trustee determines that the funds in the Benefit
     Account are  insufficient to fully pay all benefits earned or accrued as of
     any date under the Plans,  the Trustee  shall make a written  demand on the
     Company  to provide  funds in an amount  determined  by the  Trustee in its
     discretion.  The Company shall transfer such funds within fifteen (15) days
     from the time the written demand is mailed."

                                       4.

     Article 6 is  hereby  amended  by  deleting  Sections  6.1 and 6.2 in their
entirety and substituting the following in lieu thereof:

     "6.1  Prior to a Change in  Control,  this  Trust's  assets  shall be held,
     invested  and  reinvested  by  the  Trustee  in  accordance   with  written
     investment  guidelines provided by the Company from time to time. Except as
     mandated  by law,  the  Trustee  shall  not be  liable  for  following  the
     investment  guidelines  from the  Company  prior to a Change in  Control if
     there is a loss due to investments  made in accordance  with the investment
     guidelines  provided  by the  Company.  The  Trustee may invest in and hold
     securities  (including  stock or rights to acquire stock) or obligations of
     the Company,  if directed to do so in writing by the Company. In exercising
     the powers of the Company  under this Section 6.1 of Article 6, the Company
     shall act by its Corporate Treasurer or his written designees, each of whom
     is fully  authorized to exercise  such powers.  The Trustee may, and shall,
     follow the written  guidelines  signed by said Corporate  Treasurer or such
     designees.

     6.2 In  the  absence  of  written  investment  guidelines  provided  by the
     Company,  the Trustee shall invest the assets as if a Change in Control had
     occurred as provided in Section 6.3 of this Article 6 and Article 9."

                                       5.

     Section 10.1 is hereby  amended by adding the following to the beginning of
the second sentence of the present section:

     "To the extent not deducted and paid by the Company,"





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                                                             Exhibit 10(iii)A(3)

                                       6.

     Section  11.2 is hereby  amended by  deleting  the  present  section in its
entirety and substituting the following in lieu thereof:

     "11.2 (a) Except as restricted  by  securities  or other laws,  the Company
     shall  notify the  Trustee as soon as  practical  of any facts of which its
     officers have knowledge  which have caused the  commencement or termination
     of a Threatened  Change in Control  Period or the occurrence of a Change in
     Control.

     (b) The Trustee is responsible for ascertaining whether a Threatened Change
     in  Control  Period  has  commenced  and  whether a Change in  Control  has
     occurred."

                                                                              7.

     Section  18.2 is hereby  amended  by  deleting  the third  sentence  of the
present section in its entirety and substituting the following in lieu thereof:

     "Upon  receipt of such notice or any other  written  allegation,  or if the
     Trustee has actual  knowledge of the insolvency of, or of the  commencement
     of a case  under the  Bankruptcy  Code in respect  of,  the  Company or any
     Affiliate,  the Trustee  shall  suspend all  payments of benefits  from the
     Trust with respect to  Participants  and  beneficiaries  and shall hold the
     assets of the Trust for the benefit of the general creditors of the Company
     or its Affiliates."

and by adding the following at the end of the present section:

     "Provided that there are sufficient assets, if the Trustee discontinues the
     payment of benefits from the Trust and subsequently  resumes such payments,
     the first payment following such discontinuance shall include the aggregate
     amount of all payments due  Participants or their  beneficiaries  under the
     terms  of the  Plan(s)  for the  period  of such  discontinuance,  less the
     aggregate   amount  of  any  payments   made  to   Participants   or  their
     beneficiaries by the Company (or an Affiliate) in lieu of payments provided
     for hereunder during any such period of discontinuance." 8.

     Schedule 1 is hereby amended by  substituting  a revised  Schedule 1, dated
September 23, 1997, which is attached hereto and made a part hereof.




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                                                             Exhibit 10(iii)A(3)


                                       9.

     The within and  foregoing  amendments to the Trust shall be effective as of
September 23, 1997.  Except as hereby  modified,  the Trust shall remain in full
force and effect.

     IN WITNESS  WHEREOF,  the parties hereto have executed this Amendment No. 2
as of the day and year first written above.

                                     NATIONAL SERVICE INDUSTRIES, INC.

                                     By:  /s/ David Levy
                                     WACHOVIA BANK, N.A., AS TRUSTEE

                                     By: /s/

     The undersigned  Affiliates of the Corporation hereby consent to, and agree
to be bound by, this Amendment No. 2 to the Trust.

     This _23_ day of __September_______, 1997.

                                     NATIONAL SERVICE INDUSTRIES, INC.
                                    (Georgia)

                                     By:  /s/ James S. Balloun

                                     NSI ENTERPRISES, INC.

                                     By:  /s/ James S. Balloun

                                     ZEP MANUFACTURING, COMPANY

                                     By:  /s/ Glen Reed

                                     NSI SERVICES, L.P.

                                     By:  /s/ James S. Balloun