Exhibit 4.1

THIS WARRANT AND THE SHARES OF COMMON STOCK ISSUABLE UPON EXERCISE OF THIS
WARRANT HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED.
EXCEPT AS OTHERWISE SET FORTH HEREIN, NEITHER THIS WARRANT NOR ANY OF SUCH
SHARES MAY BE SOLD, TRANSFERRED OR ASSIGNED IN THE ABSENCE OF AN EFFECTIVE
REGISTRATION STATEMENT FOR SUCH SECURITIES UNDER SAID ACT OR PURSUANT TO AN
EXEMPTION THEREFROM.

SEPTEMBER 7, 2004                                            WARRANT TO PURCHASE
                                                          SHARES OF COMMON STOCK

                       ENVIRONMENTAL TECTONICS CORPORATION
                             STOCK PURCHASE WARRANT

         THIS CERTIFIES THAT, for value received, H. F. Lenfest, or his
registered assigns (each, a "HOLDER"), is entitled to purchase from
Environmental Tectonics Corporation, a Pennsylvania corporation (the "COMPANY"),
at any time or from time to time during the period specified in Section 1
hereof, Two Hundred Thousand (200,000) fully paid and nonassessable shares of
the Company's common stock, par value $0.05 per share (the "COMMON STOCK"), at
an exercise price equal to the lesser of (i) $4.00 per share or (ii) 66 2/3
percent of the Market Price (as hereinafter defined), subject to adjustment as
provided herein (the "EXERCISE PRICE"). The term "WARRANT SHARES," as used
herein, refers to the shares of Common Stock purchasable hereunder. This Warrant
has been issued pursuant to the terms of an agreement, dated as of September 7,
2004, by and between the Company and H. F. Lenfest. The term "WARRANTS" means
this Warrant and any warrants issued as a result of the transfer, exchange or
replacement of such warrants.

         This Warrant is subject to the following terms, provisions, and
conditions:

         1. PERIOD OF EXERCISE. This Warrant is exercisable at any time or from
time to time beginning on the date of issuance (the "ISSUE DATE") and ending at
5:00 p.m., Philadelphia, Pennsylvania time on the sixth (6th) anniversary of the
Issue Date (the "EXERCISE PERIOD").

         2. EXERCISE OF WARRANT. Subject to the provisions hereof, including,
without limitation, the limitations contained in Section 7 hereof, this Warrant
may be exercised by the holder hereof, in whole or in part (which such amount
shall be not less than 25,000 Warrant Shares, or a whole multiple of 5,000 in
excess thereof; provided that, the foregoing shall not apply if the remaining
Warrant Shares issuable hereunder are less than such minimum amount), by the
surrender of this Warrant, together with a completed exercise agreement in the
form attached hereto (the "EXERCISE AGREEMENT"), to the Company during normal
business hours on any business day at the Company's principal executive offices
(or such other office or agency of the Company as it may designate by notice to
the holder hereof), and upon payment to the Company in cash, by certified or
official bank check or by wire transfer for the account of the Company of the
Exercise Price for the Warrant Shares specified in the Exercise Agreement. The






Warrant Shares so purchased shall be deemed to be issued to the holder hereof or
such holder's designee, as the record owner of such shares, as of the close of
business on the date on which this Warrant shall have been surrendered, the
completed Exercise Agreement shall have been delivered and payment shall have
been made for such shares as set forth above. Certificates for the Warrant
Shares so purchased, representing the aggregate number of shares specified in
the Exercise Agreement, shall be delivered to the holder hereof within fifteen
(15) business days after this Warrant shall have been so exercised. The
certificates so delivered shall be in such denominations as may be requested by
the holder hereof and shall be registered in the name of such holder or such
other name as shall be designated by such holder. If this Warrant shall have
been exercised only in part, then, unless this Warrant has expired, the Company
shall, at its expense, as soon as practicable after the date of exercise,
deliver to the holder a new Warrant representing the number of shares with
respect to which this Warrant shall not then have been exercised.

         3. CERTAIN AGREEMENTS OF THE COMPANY. The Company hereby covenants and
agrees as follows:

            (a) SHARES TO BE FULLY PAID. All Warrant Shares will, upon issuance
in accordance with the terms of this Warrant, be validly issued, fully paid, and
nonassessable and free from all taxes, liens, and charges with respect to the
issue thereof.

            (b) RESERVATION OF SHARES. During the Exercise Period, the Company
shall at all times have authorized, and reserved for the purpose of issuance
upon exercise of this Warrant, a sufficient number of shares of Common Stock to
provide for the exercise in full of this Warrant.

            (c) LISTING. The Company shall secure the listing of the Warrant
Shares upon each securities exchange or automated quotation system, if any, upon
which shares of Common Stock are then listed (subject to official notice of
issuance upon exercise of this Warrant) and shall maintain, so long as any other
shares of Common Stock shall be so listed, such listing of all Warrant Shares.

            (d) CERTAIN ACTIONS PROHIBITED. The Company will not, by amendment
of its charter or through any reorganization, transfer of assets, consolidation,
merger, dissolution, issue or sale of securities, or any other voluntary action,
directly or indirectly, by operation of law or otherwise, avoid or seek to avoid
the observance or performance of any of the terms to be observed or performed by
it hereunder, but will at all times in good faith assist in the carrying out of
all the provisions of this Warrant and in the taking of all such action as may
reasonably be requested by the holder of this Warrant in order to protect the
exercise privilege of the holder of this Warrant against dilution or other
impairment, consistent with the tenor and purpose of this Warrant.

            (e) SUCCESSORS AND ASSIGNS. This Warrant will be binding upon any
entity succeeding to the Company or its assets.

                                       2



         4. ANTIDILUTION PROVISIONS. During the Exercise Period, the Exercise
Price and the number of Warrant Shares shall be subject to adjustment from time
to time as provided in this Section 4. In the event that any adjustment of the
Exercise Price as required herein results in a fraction of a cent, such Exercise
Price shall be rounded off to the nearest cent.

            (a) SALE OF SECURITIES BELOW CURRENT EXERCISE PRICE. Except as
otherwise provided in Sections 4(b) and 4(d), if at any time the Company shall
issue or, pursuant to the provisions hereof, be deemed to have issued (other
than as set forth in Section 4(a)(vi) hereof) any shares of Common Stock,
Convertible Securities (as hereinafter defined), Rights (as hereinafter defined)
or Related Rights (as hereinafter defined) (collectively, "SECURITIES") without
consideration or for a consideration per share less than the Exercise Price in
effect immediately prior to the issuance of such Securities, then the Exercise
Price in effect immediately prior to each such issuance shall forthwith be
reduced to the lowest per share price paid for a share of Common Stock (or
deemed paid for a share of Common Stock in the case of Rights, Convertible
Securities or Related Rights, as determined below). For the purpose of this
Section 4(a), the following definitions, procedures and exceptions shall be
applicable:

                (i) RIGHTS. In the case of the issuance of options, warrants or
         other rights to purchase or otherwise acquire shares of Common Stock,
         whether or not at the time exercisable (collectively, "RIGHTS"), the
         total number of shares of Common Stock issuable upon exercise of such
         Rights shall be deemed to have been issued at the time such Rights are
         issued, for a consideration equal to the sum of the consideration, if
         any, received by the Company upon the issuance of such Rights and the
         minimum purchase or exercise price payable upon the exercise of such
         Rights for the Common Stock to be issued upon the exercise thereof; and
         the consideration per share shall be determined by dividing (i) the
         aggregate consideration so received by and payable to the Company, by
         (ii) the number of shares of Common Stock issuable upon exercise of
         such Rights.

                (ii) CONVERTIBLE SECURITIES AND RELATED RIGHTS. In the case of
         the issuance of any class or series of stock or any bonds, debentures,
         notes or other securities or obligations convertible into or
         exchangeable for Common Stock, whether or not then convertible or
         exchangeable (collectively, "CONVERTIBLE SECURITIES"), or options,
         warrants or other rights to purchase or otherwise acquire Convertible
         Securities (collectively, "RELATED RIGHTS"), the total number of shares
         of Common Stock issuable upon the conversion or exchange of such
         Convertible Securities or exercise of such Related Rights shall be
         deemed to have been issued at the time such Convertible Securities or
         Related Rights are issued, for a consideration equal to the sum of (A)
         the consideration, if any, received by the Company upon issuance of
         such Convertible Securities or Related Rights (excluding any cash
         received on account of accrued interest or dividends) and (B)(1) in the
         case of Convertible Securities, the minimum additional consideration,
         if any, to be received by the Company upon the conversion or exchange
         of such Convertible Securities or (2) in the case of Related Rights,
         the sum of (x) the minimum purchase or exercise price payable upon the
         exercise of such Related Rights for Convertible Securities and (y) the
         minimum additional consideration, if any, to be received by the Company
         upon the conversion or exchange of the Convertible Securities issued
         upon the exercise of such Related Rights; and the consideration per

                                       3



         share shall be determined by dividing (i) the aggregate consideration
         so received by and payable to the Company, by (ii) the number of shares
         of Common Stock issuable upon conversion or exchange of such
         Convertible Securities or exercise of such Related Rights.

                (iii) CHANGES. On any change in the number of shares of Common
         Stock issuable upon the exercise of Rights or Related Rights or upon
         the conversion or exchange of Convertible Securities or on any change
         in the minimum purchase or exercise price of Rights, Related Rights or
         Convertible Securities, including, but not limited to, a change
         resulting from the anti-dilution provisions of such Rights, Related
         Rights or Convertible Securities, the Exercise Price to the extent in
         any way affected by such Rights, Related Rights or Convertible
         Securities shall forthwith be readjusted to be thereafter the Exercise
         Price that would have been obtained had the adjustment which was made
         upon the issuance of such Rights, Related Rights or Convertible
         Securities been made after giving effect to such change. No further
         adjustment shall be made in respect of such change upon the actual
         issuance of Common Stock or any payment of consideration upon the
         exercise of such Rights or Related Rights or the conversion or exchange
         of such Convertible Securities.

                (iv) EXPIRATION OR CANCELLATION. On the expiration or
         cancellation of any such Rights, Related Rights or Convertible
         Securities, if the Exercise Price shall have been adjusted upon the
         issuance thereof, the Exercise Price shall forthwith be readjusted to
         such Exercise Price as would have been obtained had the adjustment made
         upon the issuance of such Rights, Related Rights or Convertible
         Securities been made upon the basis of the issuance of only the number
         of shares of Common Stock actually issued upon the exercise of such
         Rights or Related Rights or the conversion or exchange of such
         Convertible Securities.

                (v) CASH. In the case of the issuance of such Securities for
         cash, the amount of consideration received by the Company shall be
         deemed to be the amount of cash paid therefor before deducting any
         reasonable discounts, commissions or other expenses paid or incurred by
         the Company for any underwriting or otherwise in connection with the
         issuance and sale thereof. In the case of the issuance of such
         Securities for consideration other than cash, the amount of
         consideration received by the Company shall be determined in good faith
         by the Company's Board of Directors.

                (vi) EXCEPTIONS TO ADJUSTMENT OF EXERCISE PRICE. No adjustment
         to the Exercise Price will be made (i) upon the exercise of any
         warrants, options or convertible securities issued and outstanding on
         the Issue Date in accordance with the terms of such securities as of
         such date; (ii) upon exercise of any stock or options which may
         hereafter be exercised under any employee benefit plan of the Company
         now existing or to be implemented in the future, so long as the
         issuance of such stock or options is approved by a majority of the
         non-employee members of the Board of Directors of the Company or a
         majority of the members of a committee of non-employee directors


                                       4


         established for such purpose; or (iii) upon the issuance of securities
         in connection with a strategic transaction, the primary purpose of
         which, in the good faith determination of the Board of Directors of the
         Company, is not to raise capital for the Company.

            (b) SUBDIVISION OR COMBINATION OF COMMON STOCK. If the Company at
any time subdivides (by any stock split, stock dividend, recapitalization,
reorganization, reclassification or otherwise) the shares of Common Stock
acquirable hereunder into a greater number of shares, then, after the date of
record for effecting such subdivision, the Exercise Price in effect immediately
prior to such subdivision will be proportionately reduced. If the Company at any
time combines (by reverse stock split, recapitalization, reorganization,
reclassification or otherwise) the shares of Common Stock acquirable hereunder
into a smaller number of shares, then, after the date of record for effecting
such combination, the Exercise Price in effect immediately prior to such
combination will be proportionately increased.

            (c) ADJUSTMENT IN NUMBER OF SHARES. Upon each adjustment of the
Exercise Price pursuant to the provisions of this Section 4, the number of
shares of Common Stock issuable upon exercise of this Warrant shall be adjusted
by multiplying a number equal to the Exercise Price in effect immediately prior
to such adjustment by the number of shares of Common Stock issuable upon
exercise of this Warrant immediately prior to such adjustment and dividing the
product so obtained by the adjusted Exercise Price.

            (d) CONSOLIDATION, MERGER OR SALE. In case of any consolidation of
the Company with, or merger of the Company into any other Company, or in case of
any sale or conveyance of all or substantially all of the assets of the Company
other than in connection with a plan of complete liquidation of the Company,
then as a condition of such consolidation, merger or sale or conveyance,
adequate provision will be made whereby the holder of this Warrant will have the
right to acquire and receive upon exercise of this Warrant in lieu of the shares
of Common Stock immediately theretofore acquirable upon the exercise of this
Warrant, such shares of stock, securities or assets as the holders of the
Warrants would have received had the Warrants been exercised immediately prior
to such consolidation, merger or sale or conveyance. In any such case, the
Company will make appropriate provision to insure that the provisions of this
Section 4 hereof will thereafter be applicable as nearly as may be in relation
to any shares of stock or securities thereafter deliverable upon the exercise of
this Warrant. The Company will not effect any consolidation, merger or sale or
conveyance unless prior to the consummation thereof, the successor or acquiring
entity (if other than the Company) and, if an entity different from the
successor or acquiring entity, the entity whose capital stock or assets the
holders of the Common Stock of the Company are entitled to receive as a result
of such consolidation, merger or sale or conveyance assumes by written
instrument the obligations of the Company under this Warrant (including under
this Section 4) and the obligations to deliver to the holder of this Warrant
such shares of stock, securities or assets as, in accordance with the foregoing
provisions, the holder may be entitled to acquire. This Section 4(d) shall apply
to any successive consolidations, mergers, sales or conveyances.

            (e) DISTRIBUTION OF ASSETS. In case the Company shall declare or
make any distribution of its assets (including cash) to holders of Common Stock
as a partial liquidating dividend, by way of return of capital or otherwise,
then, after the date of record for determining stockholders entitled to such
distribution, but prior to the date of distribution, the holder of this Warrant

                                       5




shall be entitled upon exercise of this Warrant for the purchase of any or all
of the shares of Common Stock subject hereto, to receive the amount of such
assets which would have been payable to the holder had such holder been the
holder of such shares of Common Stock on the record date for the determination
of stockholders entitled to such distribution.

            (f) NOTICE OF ADJUSTMENT. Upon the occurrence of any event which
requires any adjustment of the Exercise Price, then, and in each such case, the
Company shall give notice thereof to the holder of this Warrant, which notice
shall state the Exercise Price resulting from such adjustment and the increase
or decrease in the number of Warrant Shares purchasable at such price upon
exercise, setting forth in reasonable detail the method of calculation and the
facts upon which such calculation is based. Such calculation shall be certified
by the chief financial officer of the Company.

            (g) MINIMUM ADJUSTMENT OF EXERCISE PRICE. No adjustment of the
Exercise Price shall be made in an amount of less than 1% of the Exercise Price
in effect at the time such adjustment is otherwise required to be made, but any
such lesser adjustment shall be carried forward and shall be made at the time
and together with the next subsequent adjustment which, together with any
adjustments so carried forward, shall amount to not less than 1% of such
Exercise Price.

            (h) NO FRACTIONAL SHARES. No fractional shares of Common Stock are
to be issued upon the exercise of this Warrant, but the Company shall pay a cash
adjustment in respect of any fractional share which would otherwise be issuable
in an amount equal to the same fraction of the Market Price of a share of Common
Stock on the date of such exercise.

            (i) OTHER NOTICES. In case at any time:

                (i) the Company shall declare any dividend upon the Common Stock
         payable in shares of stock of any class or make any other distribution
         (including dividends or distributions payable in cash out of retained
         earnings) to the holders of the Common Stock;

                (ii) there shall be any capital reorganization of the Company,
         or reclassification of the Common Stock, or consolidation or merger of
         the Company with or into, or sale of all, substantially all or a
         material portion of its assets to, another Company or entity; or

                (iii) there shall be a voluntary or involuntary dissolution,
         liquidation or winding-up of the Company;

then, in each such case, the Company shall give to the holder of this Warrant
(a) notice of the date on which the books of the Company shall close or a record
shall be taken for determining the holders of Common Stock entitled to receive
any such dividend or distribution or for determining the holders of Common Stock
entitled to vote in respect of any such reorganization, reclassification,
consolidation, merger, sale, dissolution, liquidation or winding-up and (b) in
the case of any such reorganization, reclassification, consolidation, merger,
sale, dissolution, liquidation or winding-up, notice of the date (or, if not


                                       6



then known, a reasonable approximation thereof by the Company) when the same
shall take place. Such notice shall also specify the date on which the holders
of Common Stock shall be entitled to receive such dividend, distribution, or
subscription rights or to exchange their Common Stock for stock or other
securities or property deliverable upon such reorganization, reclassification,
consolidation, merger, sale, dissolution, liquidation, or winding-up, as the
case may be. Such notice shall be given at least ten (10) business days prior to
the record date or the date on which the Company's books are closed in respect
thereto. Failure to give any such notice or any defect therein shall not affect
the validity of the proceedings referred to in clauses (i), (ii) and (iii)
above; provided that if notice is not given in accordance with this Section
4(i), the Company will use its best efforts to insure that the holder of this
Warrant shall nevertheless receive the same rights and benefits received by
other holders of securities of the Company from the proceedings referred to in
clauses (i), (ii) and (iii) above, unless the holder of this Warrant chooses not
to receive such rights and benefits.

            (j) CERTAIN EVENTS. If any event occurs of the type contemplated by
the adjustment provisions of this Section 4 but not expressly provided for by
such provisions, the Company will give notice of such event as provided in
Section 4(i) hereof, and the Company's Board of Directors will make an
appropriate adjustment in the Exercise Price and the number of shares of Common
Stock acquirable upon exercise of this Warrant so that the rights of the holder
shall be neither enhanced nor diminished by such event.

            (k) CERTAIN DEFINITIONS.

                (i) "MARKET PRICE," as of any date, (i) means the average of the
         high and the low sale prices for the shares of Common Stock as reported
         on the American Stock Exchange ("AMEX") by Bloomberg Financial Markets
         ("BLOOMBERG") for the twenty five (25) consecutive trading days
         immediately preceding such date, or (ii) if the AMEX is not the
         principal trading market for the shares of Common Stock, the average of
         the reported closing sale prices reported by Bloomberg on the principal
         trading market for the Common Stock during the same period, or (iii) if
         the foregoing do not apply, the last sale price of such security in the
         over-the-counter market on the pink sheets or bulletin board for such
         security as reported by Bloomberg, or if no sale price is so reported
         for such security, the last bid price of such security as reported by
         Bloomberg, or (iv) if market value cannot be calculated as of such date
         on any of the foregoing bases, the Market Price shall be determined in
         good faith by the Board of Directors.

         5. ISSUE TAX. The issuance of certificates for Warrant Shares upon the
exercise of this Warrant shall be made without charge to the holder of this
Warrant or such shares for any issuance tax or other costs in respect thereof.

         6. NO RIGHTS OR LIABILITIES AS A SHAREHOLDER. This Warrant shall not
entitle the holder hereof to any voting rights, rights to dividends, or other
rights as a shareholder of the Company. No provision of this Warrant, in the
absence of affirmative action by the holder hereof to purchase Warrant Shares,
and no mere enumeration herein of the rights or privileges of the holder hereof,
shall give rise to any liability of such holder for the Exercise Price or as a
shareholder of the Company, whether such liability is asserted by the Company or
by creditors of the Company.

                                       7



         7. TRANSFER, EXCHANGE, AND REPLACEMENT OF WARRANT.

            (a) RESTRICTION ON TRANSFER. This Warrant and the rights granted to
the holder hereof are transferable, in whole or in part (which such amount shall
be not less than 25,000 Warrant Shares, or a whole multiple of 5,000 in excess
thereof; provided that, the foregoing shall not apply if the remaining Warrant
Shares issuable hereunder are less than such minimum amount), upon surrender of
this Warrant, together with a properly executed assignment in the form attached
hereto, at the office or agency of the Company referred to in Section 7(e)
below; provided, however, that any transfer or assignment shall be subject to
the conditions set forth in Section 7(f). Notwithstanding the foregoing, this
Warrant, the shares of Common Stock issuable upon exercise hereof, and the
rights granted hereunder may not be transferred to a competitor of the Company
or any Subsidiary or affiliate of the Company.

            (b) WARRANT EXCHANGEABLE FOR DIFFERENT DENOMINATIONS. This Warrant
is exchangeable, upon the surrender hereof by the holder hereof at the office or
agency of the Company referred to in Section 7(e) below, for new Warrants of
like tenor representing in the aggregate the right to purchase the number of
shares of Common Stock which may be purchased hereunder, each of such new
Warrants to represent the right to purchase such number of shares as shall be
designated by the holder hereof at the time of such surrender.

            (c) REPLACEMENT OF WARRANT. Upon receipt of evidence of the loss,
theft, destruction, or mutilation of this Warrant and, in the case of any such
loss, theft, or destruction, upon delivery of an indemnity agreement reasonably
satisfactory in form and amount to the Company, or, in the case of any such
mutilation, upon surrender and cancellation of this Warrant, the Company, at its
expense, will execute and deliver, in lieu thereof, a new Warrant of like tenor.

            (d) CANCELLATION; PAYMENT OF EXPENSES. Upon the surrender of this
Warrant in connection with any transfer, exchange, or replacement as provided in
this Section 7, this Warrant shall be promptly canceled by the Company. The
Company shall pay all taxes (other than securities transfer taxes) and all other
expenses (other than legal expenses, if any, incurred by the holder or
transferees) and charges payable in connection with the preparation, execution,
and delivery of Warrants pursuant to this Section 7.

            (e) REGISTER. The Company shall maintain, at its principal executive
offices (or such other office or agency of the Company as it may designate by
notice to the holder hereof), a register for this Warrant, in which the Company
shall record the name and address of the person in whose name this Warrant has
been issued, as well as the name and address of each transferee and each prior
owner of this Warrant.

            (f) EXERCISE OR TRANSFER WITHOUT REGISTRATION. If, at the time of
the surrender of this Warrant in connection with any exercise, transfer, or
exchange of this Warrant, this Warrant (or, in the case of any exercise, the
Warrant Shares issuable hereunder), shall not be registered under the Securities
Act and under applicable state securities or blue sky laws, the Company may
require, as a condition of allowing such exercise, transfer, or exchange, that
the holder or transferee of this Warrant, as the case may be, furnish to the


                                       8




Company a written opinion of counsel to the effect that such exercise, transfer,
or exchange may be made without registration under the Securities Act and under
applicable state securities or blue sky laws; provided however, that no legal
opinion shall be required in connection with a transfer pursuant to Rule 144
under the Securities Act unless in the opinion of counsel to the Company, such
transfer does not comply with the provisions of Rule 144. Notwithstanding the
foregoing, the initial holder of this Warrant, by taking and holding the same,
represents to the Company that such holder is acquiring this Warrant for
investment and not with a present view to the distribution thereof.

         8. NOTICES. Any notice which is required or provided to be given under
this Warrant shall be deemed to have been sufficiently given and received for
all purposes when delivered by hand, telecopy (if a copy of such confirmed
telecopy transmission shall be contemporaneously sent by first class mail), or
nationally recognized overnight courier, or five days after being sent by
certified or registered mail, postage and charges prepaid, return receipt
requested, to the following addresses:

         If to the Company:

                  Environmental Tectonics Corporation
                  125 James Way
                  Southampton, PA 18966
                  Attention:  Chief Financial Officer
                  Facsimile:  (215) 357-4000








                                       9



         With a copy to:

                  Klehr, Harrison, Harvey, Branzburg & Ellers LLP
                  260 S. Broad Street
                  Philadelphia, PA  19102
                  Attention:  William W. Matthews, III, Esquire
                  Facsimile:  (215) 568-6603

         If to a holder hereof, at the address shown for such holder on the
books of the Company; or, with respect to any party hereto, at any other address
designated in writing by such party in accordance with the provisions of this
Section 8.

         9. GOVERNING LAW; JURISDICTION. This Warrant shall be governed by and
construed in accordance with the laws of the Commonwealth of Pennsylvania
applicable to agreements made and to be performed in the Commonwealth of
Pennsylvania (without regard to principles of conflict of laws). The Company and
the holder hereof consent to the jurisdiction of the United States federal
courts and the state courts located in the Commonwealth of Pennsylvania with
respect to any suit or proceeding based on or arising under this Warrant or the
transactions contemplated hereby and agree that all claims in respect of such
suit or proceeding may be determined in such courts. The Company and the holder
hereof waive the defense of an inconvenient forum to the maintenance of such
suit or proceeding and agree that service of process upon a party mailed by
first class mail shall be deemed in every respect effective service of process
upon the party in any such suit or proceeding. Nothing herein shall affect
either party's right to serve process in any other manner permitted by law.

         10. MISCELLANEOUS.

            (a) AMENDMENTS. This Warrant and any provision hereof may only be
amended by an instrument in writing signed by the Company and a majority in
interest of the outstanding Warrants.

            (b) DESCRIPTIVE HEADINGS. The descriptive headings of the several
paragraphs of this Warrant are inserted for purposes of reference only, and
shall not affect the meaning or construction of any of the provisions hereof.

                            [SIGNATURE PAGE FOLLOWS]








                                       10




       IN WITNESS WHEREOF, the Company has caused this Warrant to be signed by
its duly authorized officer.

                                    ENVIRONMENTAL TECTONICS CORPORATION


                                    By: Duane D. Deaner
                                        Name:  Duane Deaner
                                        Title: C.F.O.



                                    Dated as of September 7, 2004







                           FORM OF EXERCISE AGREEMENT


                                                        Dated: ________ __, 20__


To:   [Company]
      [Address]


         The undersigned, pursuant to the provisions set forth in the Warrant
attached hereto, hereby agrees to purchase ________ shares of Common Stock
covered by such Warrant, and makes payment herewith in full therefor at the
price per share provided by such Warrant in cash, by wire transfer or by
certified or official bank check in the amount of $______________. Please issue
a certificate or certificates for such shares of Common Stock in the name of and
pay any cash for any fractional share to:


                                   Name:________________________________________

                                   Signature:___________________________________
                                   Address:  ___________________________________
                                             ___________________________________


                                   Note: The above signature should correspond
                                         exactly with the name on the face
                                         of the within Warrant.

and, if said number of shares of Common Stock shall not be all the shares
purchasable under the within Warrant, a new Warrant is to be issued in the name
of said undersigned covering the balance of the shares purchasable thereunder
less any fraction of a share paid in cash.





                               FORM OF ASSIGNMENT


         FOR VALUE RECEIVED, the undersigned hereby sells, assigns, and
transfers all the rights of the undersigned under the within Warrant, with
respect to the number of shares of Common Stock covered thereby set forth
hereinbelow, to:

Name of Assignee                  Address                          No. of Shares
- ----------------                  -------                          -------------





, and hereby irrevocably constitutes and appoints_______________________________
______________________________________ as agent and attorney-in-fact to transfer
said Warrant on the books of the within-named Company, with full power of
substitution in the premises.


Dated: _________________ __, 20__

In the presence of:



_________________________________

                                        Name:__________________________________

                                        Signature:_____________________________

                                        Title of Signing Officer
                                        or Agent (if any):
                                                 ______________________________
                                        Address: ______________________________
                                                 ______________________________


                                        Note: The above signature should
                                              correspond exactly with the name
                                              on the face of the within Warrant.