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                                                           Exhibit 10(iii)A48(c)

                               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."

                                       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.
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         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,"

                                       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


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         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.

                                       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:
                                       ----------------------------------------
                                       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 ___ day of __________________, 1997.

                                    NATIONAL SERVICE INDUSTRIES, INC.
                                    (Georgia)



                                    By:  /s/ James S. Balloun
                                       ----------------------------------------

                                    NSI ENTERPRISES, INC.



                                    By:  /s/ James S. Balloun
                                       ----------------------------------------

                                    ZEP MANUFACTURING, COMPANY



                                    By:  /s/ James S. Balloun
                                       ----------------------------------------

                                    NSI SERVICES, L.P.



                                    By:  /s/ James S. Balloun
                                       ----------------------------------------


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