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                                                                   Exhibit 10.24

                                   ATMI, INC.
                        RESTRICTED STOCK GRANT AGREEMENT

          THIS AGREEMENT, made as of the ___ day of _____________, between ATMI,
Inc. (the "Company") and __________________ (the "Participant").

          WHEREAS, the Company has adopted and maintains the ATMI, Inc. 2003
Stock Plan (the "Plan"), attached hereto as Exhibit A;

          WHEREAS, the Plan provides that the Board of Directors of the Company
shall administer the Plan and determine the key persons to whom awards shall be
granted and the amount and type of such awards; and

          WHEREAS, the Board of Directors has determined that the purposes of
the Plan would be furthered by granting the Participant an award under the Plan
as set forth in this Agreement;

          NOW, THEREFORE, in consideration of the premises and the mutual
covenants hereinafter set forth, the parties hereto hereby agree as follows:

          1. Grant of Restricted Stock. Pursuant to, and subject to, the terms
and conditions set forth herein and in the Plan, the Board of Directors hereby
grants to the Participant _____ restricted shares (the "Restricted Stock") of
common stock of the Company, par value $0.01 per share ("Common Stock").

          2. Grant Date. The Grant Date of the Restricted Stock is ________,
____.

          3. Incorporation of Plan. All terms, conditions and restrictions of
the Plan are incorporated herein and made part hereof as if stated herein. If
there is any conflict between the terms and conditions of the Plan and this
Agreement, the terms and conditions of the Plan, as interpreted by the Board of
Directors, shall govern. Except as otherwise provided herein, all capitalized
terms used herein shall have the meaning given to such terms in the Plan.

          4. Vesting. Subject to the further provision of this Agreement, the
Restricted Stock shall vest with respect to a number of whole shares as close as
possible to the following percentage of the total number of shares of Restricted
Stock granted hereunder on the following dates (each, a "Vesting Date"):

<TABLE>
<CAPTION>
PERCENTAGE OF TOTAL SHARES             VESTING DATE
--------------------------             ------------
<S>                          <C>
            50%              Third anniversary of Grant Date
            25%              Fourth anniversary of Grant Date
            25%              Fifth anniversary of Grant Date
</TABLE>

          5. Restrictions on Transferability. Until a share of Restricted Stock
vests, such share may not be sold, assigned, transferred, alienated, commuted,
anticipated, or otherwise disposed of (except by will or the laws of descent and
distribution), or pledged or hypothecated as collateral for a loan or as
security for the performance of any obligation, or be otherwise


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encumbered, and are not subject to attachment, garnishment, execution or other
legal or equitable process, and any attempt to do so shall be null and void. If
the Participant attempts to dispose of or encumber the Participant's unvested
shares of Restricted Stock, such shares of Restricted Stock, together with any
property in respect of such shares held by the custodian pursuant to Section 8
hereof, shall be forfeited as of the date of such attempted transfer and the
Participant promptly shall return to the Company any certificates evidencing
such shares.

          6. Termination of Employment. In the event that the Participant's
employment with the Company or one of the Company's subsidiaries terminates for
any reason, all unvested shares of Restricted Stock, together with any property
in respect of such shares held by the custodian pursuant to Section 8 hereof,
shall be forfeited as of the date of such termination of employment and the
Participant promptly shall return to the Company any certificates evidencing
such shares. For purposes of this Agreement, the Participant shall be deemed to
have a terminated employment or incurred a termination of employment upon (i)
the date the Participant ceases to be employed by, or to provide consulting
services for, the Company or any Company subsidiary; or (ii) the date the
Participant ceases to be a Board member, provided, however, that if the
Participant (x) at the time of reference is both an employee or consultant and a
Board member, or (y) ceases to be engaged as an employee, consultant or Board
member and immediately is engaged in another of such relationships with the
Company or any Company subsidiary, the Participant shall not be deemed to have a
"termination of employment" until the last of the dates determined pursuant to
subparagraphs (i) and (ii) above. The Committee, in its discretion, may
determine whether any leave of absence constitutes a termination of employment
for purposes of this Agreement.

          7. Issuance of Certificates.

          (a) Reasonably promptly after the Grant Date, the Company shall issue
and deliver to the Participant stock certificates, registered in the name of the
Participant, evidencing the shares of Restricted Stock. Each such certificate
may bear the following legend:

     "THE SALE, TRANSFER, ASSIGNMENT, PLEDGE, HYPOTHECATION ENCUMBRANCE OR OTHER
     DISPOSAL OF THE SECURITIES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO
     THE TERMS OF THE ATMI, INC. 2003 STOCK PLAN AND A RESTRICTED STOCK GRANT
     AGREEMENT BETWEEN ATMI, INC. AND THE HOLDER OF RECORD OF THE SECURITIES
     REPRESENTED BY THIS CERTIFICATE. NO TRANSFER OF THE SECURITIES REPRESENTED
     BY THIS CERTIFICATE IN CONTRAVENTION OF SUCH PLAN AND RESTRICTED STOCK
     GRANT AGREEMENT SHALL BE VALID OR EFFECTIVE. COPIES OF SUCH AGREEMENT MAY
     BE OBTAINED BY WRITTEN REQUEST MADE BY THE HOLDER OF RECORD OF THE
     CERTIFICATE TO THE SECRETARY OF ATMI, INC."

Such legend shall not be removed from such certificates until such shares of
Restricted Stock vest.


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          (b) Reasonably promptly after any such shares of Restricted Stock vest
pursuant to Section 4 hereof, in exchange for the surrender to the Company of
the certificates evidencing such shares of Restricted Stock delivered to the
Participant under Section 7(a) hereof, the Company shall issue and deliver to
the Participant (or the Participant's legal representative, beneficiary or heir)
certificates evidencing such shares of Restricted Stock, free of the legend
provided in Section 7(a) hereof, together with any property in respect of such
shares held by the custodian pursuant to Section 8 hereof.

          (c) The Company may require as a condition of the delivery of stock
certificates pursuant to Section 7(b) hereof that the Participant remit to the
Company an amount sufficient in the opinion of the Company to satisfy any
federal, state and other governmental tax withholding requirements related to
the vesting of the shares represented by such certificate.

          (d) The Participant shall not be deemed for any purpose to be, or have
rights as, a shareholder of the Company by virtue of the grant of Restricted
Stock, except to the extent a stock certificate is issued therefor pursuant to
Section 7(a) hereof, and then only from the date such certificate is issued.
Upon the issuance of a stock certificate, the Participant shall have the rights
of a shareholder with respect to the Restricted Stock, including the right to
vote the shares, subject to the restrictions on transferability, the forfeiture
provisions and the requirement that dividends be held in escrow until the shares
vest, as set forth in this Agreement.

          8. Dividends, etc. Unless the Board of Directors otherwise determines,
any property, including cash dividends, received by a Participant with respect
to a share of Restricted Stock as a result of any dividend, recapitalization,
merger, consolidation, combination, exchange of shares or otherwise and for
which the Grant Date occurs prior to such event but which has not vested as of
the date of such event, will not vest until such share of Restricted Stock
vests, and shall be promptly deposited with the Company or a custodian
designated by the Company. The Company shall or shall cause such custodian to
issue to the Participant a receipt evidencing the property held by it in respect
of the Restricted Stock.

          9. Delays or Omissions. No delay or omission to exercise any right,
power or remedy accruing to any party hereto upon any breach or default of any
party under this Agreement, shall impair any such right, power or remedy of such
party, nor shall it be construed to be a waiver of any such breach or default,
or an acquiescence therein, or of or in any similar breach or default thereafter
occurring, nor shall any waiver of any single breach or default be deemed a
waiver of any other breach or default theretofore or thereafter occurring. Any
waiver, permit, consent or approval of any kind or character on the part of any
party of any breach or default under this Agreement, or any waiver on the part
of any party or any provisions or conditions of this Agreement, must be in a
writing signed by such party and shall be effective only to the extent
specifically set forth in such writing.

          10. Right of Discharge Preserved. Nothing in this Agreement shall
confer upon the Participant the right to continue in the employ or other service
of the Company or one of the Company's subsidiaries, or affect any right which
the Company may have to terminate such employment or service.


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          11. Integration. This Agreement contains the entire understanding of
the parties with respect to its subject matter. There are no restrictions,
agreements, promises, representations, warranties, covenants or undertakings
with respect to the subject matter hereof other than those expressly set forth
herein. This Agreement, including, without limitation, the Plan, supersedes all
prior agreements and understandings between the parties with respect to its
subject matter.

          12. Counterparts. This Agreement may be executed in two or more
counterparts, each of which shall be deemed an original, but all of which shall
constitute one and the same instrument.

          13. Governing Law. This Agreement shall be governed by and construed
and enforced in accordance with the laws of the State of Connecticut, without
regard to the provisions governing conflict of laws.

          14. Participant Acknowledgment. The Participant hereby acknowledges
receipt of a copy of the Plan. The Participant hereby acknowledges that all
decisions, determinations and interpretations of the Board of Directors in
respect of the Plan, this Agreement and the Restricted Stock shall be final and
conclusive.

          IN WITNESS WHEREOF, the Company has caused this Agreement to be duly
executed by its duly authorized officer, and the Participant has hereunto signed
this Agreement on his own behalf, thereby representing that he has carefully
read and understands this Agreement and the Plan as of the day and year first
written above.

                                        ATMI, INC.


                                        By:
                                            ------------------------------------
                                        Name:
                                        Title:

                                        ----------------------------------------
                                        [Participant]


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