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                                                                 EXHIBIT 10.9(b)

                                 AMENDMENT NO. 5
                                     TO THE
                        NATIONAL SERVICE INDUSTRIES, INC.
                         SENIOR MANAGEMENT BENEFIT PLAN


         THIS AMENDMENT made as of the 1st day of October, 2001, by National
Service Industries, Inc., a Delaware corporation ("NSI");

                              W I T N E S S E T H:

         WHEREAS, NSI has previously established the National Service
Industries, Inc. Senior Management Benefit Plan (the "Plan") for the benefit of
its eligible employees and their beneficiaries; and

         WHEREAS, in connection with the planned distribution of the shares of
common stock of Acuity Brands, Inc. to the stockholders of NSI (the "Spin-Off"),
NSI desires to amend the Plan to permit former employees of NSI and its
subsidiaries who did not work for Acuity Brands, Inc. or its subsidiaries to
make a one-time irrevocable election to receive a lump sum distribution of their
benefit under the Plan; and

         WHEREAS, in connection with the Spin-Off, NSI also desires to amend the
Plan to provide for the transfer of accounts for certain employees and former
employees of Acuity Brands, Inc. and its subsidiaries to a deferred compensation
plan being established by Acuity Brands, Inc.;

         WHEREAS, pursuant to the power of amendment contained in Section 11.4
of the Plan, the Plan is hereby amended as follows:

                                       1.

         Effective as of October 1, 2001, the Plan is hereby amended by
inserting the following as a new section 5.6:

         "5.6 Special Payment Election. In connection with, and contingent upon,
         the spin-off of NSI's lighting equipment and chemicals businesses
         ("Spin-Off Businesses") to a separate, publicly-traded company,
         Participants who did not work for the Spin-Off Businesses or the
         portion of the corporate office of the Employer being transferred in
         the Spin-Off (and beneficiaries of such Participants) shall have the
         right to make a one-time irrevocable election to receive a lump sum
         distribution of their Deferred Benefit Account in the Plan. The
         Participant may make such an election during such time period and using
         such form as provided by the Plan Committee. A Participant making such
         an election shall cease to be eligible to participate in the Plan. If
         no such election is made, the Participant's Retirement Benefit shall be
         payable as provided in Section 5.5."

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                                       2.

         Effective as of November 30, 2001, the Plan is hereby amended by
inserting the following as a new Section 11.6:

                  "11.6 Spin-Off of Acuity Brands, Inc. - Transfer of Accounts.
         Pursuant to an Employee Benefits Agreement dated as of November 30,
         2001, between the Employer and Acuity Brands, Inc. ("Acuity") and in
         connection with the distribution of the shares of Acuity to the
         stockholders of the Employer (the "Spin-Off"), the Deferred Benefit
         Account of each Participant who becomes or remains an employee of
         Acuity or its subsidiaries as of November 30, 2001 and of each
         Participant (including Participants and their beneficiaries in pay
         status) who was formerly employed by the businesses transferred to
         Acuity by the Employer (including former employees of the corporate
         office of the Employer), shall be transferred to the Acuity Brands,
         Inc. Senior Management Benefit Plan ("Acuity Plan") as of November 30,
         2001 or as soon as practical thereafter. For purposes of this Plan and
         the Acuity Plan, each Participant who becomes a Participant in the
         Acuity Plan shall not be deemed to have retired from full-time
         employment with the Employer solely as a result of the Spin-Off."

                                       3.

         Effective as of November 30, 2001, the Plan is hereby amended by
incorporating the following as the new Appendix 1:

                                   "Appendix 1
                               Adopting Employers

         National Service Industries, Inc. (CA) f/k/a NSI Enterprises, Inc."

                                       4.

         Except as provided herein, the provisions of the Plan shall remain in
full force and effect.

         IN WITNESS WHEREOF, NSI has caused this Amendment No. 5 to be executed
by its duly authorized corporate officers as of the date and year first written
above.


ATTEST:                                     NATIONAL SERVICE INDUSTRIES, INC.


By: /s/ Helen Haines                        By: /s/  Brock A. Hattox
    ----------------                            --------------------
    Secretary