Exhibit 3.1
                      RESTATED CERTIFICATE OF INCORPORATION
                                       OF
                           MEDICAL STERILIZATION, INC.
              Under Section 807 of the Business Corporation Law

      We, Kennard H. Morganstern and Harvey Cohen, being respectively the
President and Secretary of Medical Sterilization, Inc. hereby certify:
      1.    The name of the corporation is Medical Sterilization, Inc.
      2.    The Certificate of Incorporation was filed on May 27, 1982
under the name, General Sterilization Services, Inc.  Restated Certificates
of Incorporation were filed on May 12, 1983 and August 5, 1983.
      3.    The Certificate of Incorporation is amended as follows:
            (a)   to increase the authorized number of shares of Common
Stock from Five Million (5,000,000) to Ten Million (10,000,000); 
            (b) to eliminate the Class A Convertible Non-Cumulative
Preferred Stock and the Class B Convertible Non-Cumulative Preferred Stock;
the shares being eliminated are not issued;
            (c) to authorize the issuance of 3,000,000 shares of Preferred Stock
issuable in series, par value .01 per share.
      4.    The Certificate of Incorporation is hereby restated to set
forth its entire text as amended:

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      "FIRST:  The name of the corporation shall be Medical Sterilization,
Inc.
      SECOND:  The purposes for which it is formed are:
            A.    To engage in the business of providing sterilization
services for business and institutions, supplying and/or leasing materials,
instruments and equipment, experimenting with, developing, producing, buying,
renting, leasing, maintaining, servicing, repairing and generally dealing in all
types of sterilization equipment, x-ray equipment and instruments, electronic
and nuclear equipment, scientific apparatus and instruments, and all other
articles and equipment of kindred nature, and to engage in the business of
acting as scientific consultants in connection with the above.
            B. To own, operate and control, to lease, manage, take over or in
any lawful manner acquire any business, factory, warehouse, plant, office, store
or establishment for the carrying on of the business of the corporation and for
the purchase, sale, import, export, manufacture, fabrication, production or
storage of all kinds of goods, wares, merchandise of any and all descriptions.
            C. To do all and everything necessary, suitable or proper for the
accomplishment of any of the purposes, the attainment of any of the objects, or
the furtherance of any of the powers hereinbefore set forth, either alone or in
connection with other corporations, firms, or individuals, and either as
principals or agents, and to do every other act or acts, thing or things,
incidental or appurtenant to or growing out of or connected with the aforesaid
objects, purposes, or powers, or any of them.
      THIRD:  The office of the corporation is to be located in the Village
of Garden City, County of Nassau.

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      FOURTH: The aggregate number of shares which the corporation shall have
authority to issue is Thirteen Million (13,000,000) shares to consist of Ten
Million (10,000,000) shares of Common Stock, with a par value of $.01 per share
and Three Million (3,000,000) shares of Preferred Stock, with a par value of
$.01 per share.
      The respective designations, preferences, privileges and voting powers or
restrictions or qualifications of each class of stock are as follows:
            A. Preferred Stock. The Preferred Stock may be issued from time to
time in one or more series and with such designation for each such series as
shall be stated and expressed in the resolution or resolutions providing for the
issue of each such series adopted by the Board of Directors. The Board of
Directors in any such resolution or resolutions is expressly authorized to state
and express for each such series:
                  (i) Voting rights, if any, including without limitation the
authority to confer multiple votes per share, voting rights as to specified
matters or issues such as mergers, consolidations or sales of assets, or voting
rights to be exercised either together with holders of Common Stock as a single
class, or independently as a separate class;
                  (ii) The rate per annum and the times at and conditions upon
which the holders of stock of such series shall be entitled to receive
dividends, and whether such dividends shall be cumulative or non-cumulative and
if cumulative the terms upon which such dividends shall be cumulative;
                  (iii) The price or prices and the time or times at and
the manner in which the stock of such series shall be redeemable;

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                  (iv) The rights to which the holders of the shares of stock of
such series shall be entitled upon any voluntary or involuntary liquidation,
dissolution or winding up of the Corporation;
                  (v) The terms, if any, upon which the shares of stock of such
series shall be convertible into, or exchangeable for, shares of stock of any
other class or classes or of any other series of the same or any other class or
classes, including the price or prices or the rate or rates of conversion or
exchange and the terms of adjustment, if any; and
                  (vi) Any other designations, preferences and relative,
participating, optional or other special rights, and qualifications, limitations
or restrictions thereof so far as they are not inconsistent with the provisions
of the Certificate of Incorporation, as amended, and to the full extent now or
hereafter permitted by the laws of the State of New York.
                  All shares of the Preferred Stock of any one series shall be
identical to each other in all aspects, except that shares of any one series
issued at different times may differ as to the dates from which dividends
thereon, if cumulative, shall be cumulative.
            B.    Common Stock.
                  (i) Whenever dividends upon the Preferred Stock at the time
outstanding shall have been paid in full for all past dividend periods or
declared and set apart for payment, such dividends as may be determined by the
Board of Directors may be declared by the Board of Directors and paid from time
to time to the holders of the Common Stock, subject to any restrictions stated
and expressed in any resolution or resolutions adopted by the Board of Directors
including any resolutions providing for the issuance of Preferred Stock.
                  (ii) In the event of any liquidation, dissolution or winding
up of the affairs of the Corporation, whether voluntary or involuntary, all
assets remaining after the

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payment to the holders of the Preferred Stock at the time outstanding of the
full amounts to which they shall be entitled, shall be divided and distributed
among the holders of Common Stock according to their respective shares.
                  (iii) Each holder of the Common Stock shall have one vote in
respect of each share of such stock held by him.
            C. Pre-emptive Rights. No shareholder of this corporation shall have
a pre-emptive right because of his shareholdings to have first offered to him
any part of any of the presently authorized shares of this corporation hereafter
issued, optioned, or sold, or any part of any debenture, bonds, notes, or
securities of this corporation convertible into shares hereafter issued,
optioned, or sold by the corporation. This provision shall operate to defeat
rights in all shares and classes of shares now authorized and in all debentures,
bonds, notes, or securities of the corporation which may be convertible into
shares, and also to defeat pre-emptive rights in any and all shares and classes
of shares and securities convertible into shares which this corporation may be
hereafter authorized to issue by any amended certificate duly filed. Thus, any
and all of the shares of this corporation presently authorized, and any and all
debentures, bonds, notes, or securities of this corporation convertible into
shares and any and all of the shares of this corporation which may hereafter be
authorized, may at any time be issued, optioned, and contracted for sale, and/or
sold and disposed of by direction of the Board of Directors of this corporation
to such persons, and upon such terms and conditions as may to the Board of
Directors seem proper and advisable, without first offering the said shares or
securities or any part thereof to existing shareholders.
            D.    Stock Rights and Options.  The corporation shall have the
power to create and issue rights, warrants, or options entitling the
holders thereof to purchase from the

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corporation any shares of its capital stock of any class or classes, upon such
terms and conditions and at such time and prices as the Board of Directors may
provide, which terms and conditions shall be incorporated in an instrument or
instruments evidencing such rights. In the absence of fraud, the judgment of the
Directors as to the adequacy of consideration for the issuance of such rights or
options and the sufficiency thereof shall be conclusive.

      FIFTH: The Secretary of State is designated as the agent of the
corporation upon whom process against it may be served, and the post office
address to which the Secretary of State shall mail a copy of such process served
upon him is c/o Murtagh, Cohen & Byrne, 1122 Franklin Avenue, Garden City, New
York 11530."
      5. The Restatement of the Certificate of Incorporation was authorized by
the vote of the Board, followed by the affirmative vote of the holders of a
majority of all outstanding shares entitled to vote thereon at a meeting of
shareholders.
      IN WITNESS WHEREOF, we have signed this Restated Certificate of
Incorporation on the 22nd day of May, 1989.


                                     ------------------------------------
                                            Kennard H. Morganstern
                                                  President


                                     ------------------------------------
                                                 Harvey Cohen
                                                   Secretary

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STATE OF NEW YORK )
                  )ss.:
COUNTY OF NASSAU  )

      On this 22nd day of May, 1989, before me personally came KENNARD H.
MORGANSTERN and HARVEY COHEN, to me known to be the individual's described in
and who executed the foregoing Restated Certificate of Incorporation, and they
duly acknowledged to me they executed the same.



                                     ------------------------------------
                                                Notary Public





393LMM5962/1.195515_1


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