AMENDED AND RESTATED SUBORDINATION AND INTERCREDITOR AGREEMENT

Exhibit 10.4

AMENDED AND RESTATED SUBORDINATION AND

     This Amended and Restated Subordination and Intercreditor Agreement (this “ Agreement ”) is dated as of July 31, 2007 among PNC BANK, NATIONAL ASSOCIATION (the “ Bank ”), SUBORDINATED LENDER (as defined below), and ENVIRONMENTAL TECTONICS CORPORATION , a Pennsylvania corporation (“ Company ”).

BACKGROUND

     As an inducement for Bank to continue and increase a credit facility in favor of Company, Subordinated Lender has agreed to enter into this Agreement to provide for the subordination of (i) the Subordinated Indebtedness (as defined below) and (ii) the Liens (as defined below) in the assets of Company granted to Subordinated Lender to the prior payment of Senior Indebtedness (as defined below) and to any Liens granted to Bank. This Agreement restates and replaces (but does not constitute a novation of) the existing Restated Subordination and Intercreditor Agreement among Bank, Subordinated Lender and Company dated as of November 16, 2006.

AGREEMENTS

     NOW, THEREFORE, for good and valuable consideration, receipt of which is hereby acknowledged, the parties hereto agree as follows:

     1.  Definitions .

     1.1 General Terms . For purposes of this Agreement, the following terms shall have the following meanings:

     “ Bank ” shall have the meaning set forth in the introductory paragraph of this Agreement and any successor, assign or other provider of the Senior Indebtedness.

     “ Collateral ” shall mean all of the property and interests in property, tangible or intangible, real or personal, now owned or hereafter acquired by Company or the Guarantor in or upon which Bank and/or Subordinated Lender at any time has a Lien, and including, without limitation, all proceeds and products of such property and interests in property and any guaranty by the Guarantor.

     “ Company ” shall mean Company and its successors and assigns.

     “ Creditor Agreements ” shall mean, collectively, the Senior Lending Agreements and the Subordinated Lending Agreements.

     “ Creditors ” shall mean, collectively, Bank and Subordinated Lender and their respective successors and assigns.

     “ Default ” shall have the meaning given to the term “Default” set forth in the Loan Agreement.

     “ Distribution ” shall mean any payment in cash or any other property (other than securities of the Company into which the Subordinated Indebtedness is convertible pursuant to the terms of the Subordinated Note), or security for any such Distribution.

     “ Event of Default ” shall have the meaning given to the term “Event of Default” in any of the Senior Lending Agreements.

     “ Guarantor ” shall mean H.F. Lenfest, an individual.

     “ Insolvency Event ” shall have the meaning set forth in Section 2.2(c) hereof.

     “ Lien ” shall mean any mortgage, deed of trust, pledge, hypothecation, assignment, deposit arrangement, security interest, encumbrance (including, but not limited to, easements, rights of way and the like), lien (statutory or other), security agreement or transfer intended as security including, without limitation, any conditional sale or other title retention agreement, the interest of a lessor under a capital lease or any financing lease having substantially the same economic effect as any of the foregoing.

     “ Loan Agreement ” shall mean the amended and restated Letter Agreement, dated as of the date hereof, between Company and Bank, as the same may be amended, supplemented, modified or restated from time to time.

     “ Note Purchase Agreement ” shall mean the Convertible Note and Warrant Purchase Agreement dated as of February 18, 2003 between Company and Subordinated Lender, as the same has and may be amended, supplemented, modified or restated from time to time.

     “ Person ” shall mean an individual, a partnership, a corporation (including a business trust), a joint stock company, a trust, an unincorporated association, a joint venture, a limited liability company, a limited liability partnership or other entity, or a government or any agency, instrumentality or political subdivision thereof.

     “ Secured Lender Remedies ” shall mean any action which results in the sale, foreclosure, realization upon, or a liquidation of any of the Collateral including, without limitation, the exercise or any of the rights or remedies of a “secured party” under Article 9 of the Uniform Commercial Code, such as, without limitation, the notification of account debtors.

     “ Senior Indebtedness ” shall mean all obligations of any kind owed by Company or the Guarantor to Bank from time to time under or pursuant to any of the Senior Lending Agreements including, without limitation, all principal, interest accruing thereon, charges, expenses, fees and other sums (including all interest, charges, expenses, fees and other sums accruing after commencement of any case, proceeding or other action relating to the bankruptcy, insolvency or reorganization of Company) chargeable to Company or Guarantor by Bank, and reimbursement, indemnity or other obligations due and payable to Bank. Senior Indebtedness shall continue to constitute Senior Indebtedness, notwithstanding the fact that such Senior Indebtedness or any claim for such Senior Indebtedness is subordinated, avoided or disallowed under the federal

Bankruptcy Code or other applicable law. Senior Indebtedness shall also include any indebtedness of Company incurred in connection with a refinancing of the Senior Indebtedness under the Senior Lending Agreements if the terms and conditions of the agreements, documents and instruments related to such refinancing, taken as a whole, are not materially more onerous to Subordinated Lender than those set forth in the Senior Lending Agreements, as in effect on the date hereof. The principal portion of the Senior Indebtedness and the principal amount subject to this Agreement shall in no event exceed $20,000,000.

     “ Subordinated Lender ” shall mean H.F. Lenfest and any other Person(s) at any time or in any manner acquiring any right or interest in any of the Subordinated Indebtedness.

     “ Senior Lending Agreements ” shall mean collectively the Loan Agreement and the Loan Documents together with any other agreements, documents and instruments at any time evidencing, securing or related to the Senior Indebtedness, each as from time to time in effect.

     “ Subordinated Indebtedness ” shall mean all principal, interest and other amounts payable or chargeable in connection with the Subordinated Note.

     “ Subordinated Lending Agreements ” shall mean, collectively, the Note Purchase Agreement, the Subordinated Note and all promissory notes, guaranties, agreements, documents and instruments now or at any time hereafter executed and/or delivered by Company, Guarantor or any other person to, with or in favor of Subordinated Lender in connection therewith or related thereto (other than the warrants issued simultaneously with the Subordinated Note and the documents and agreements executed in connection therewith or related thereto), as all of the foregoing now exist or may hereafter be amended, modified, supplemented, extended, renewed, restated or replaced.

     “ Subordinated Note ” shall mean collectively the convertible promissory note issued by Company to Subordinated Lender in the original aggregate principal amount of $10,000,000 dated February 18, 2003 issued pursuant to the Note Purchase Agreement, together with any extensions thereof, or modifications or amendments thereto or replacements and substitutions therefor.

     1.2 Other Terms . Capitalized terms not otherwise defined herein shall have the meanings given to them in the Loan Agreement.

     1.3 Certain Matters of Construction . The terms “herein”, “hereof and “hereunder” and other words of similar import refer to this Agreement as a whole and not to any particular section, paragraph or subdivision. Any pronoun used shall be deemed to cover all genders. Wherever appropriate in the context, terms used herein in the singular also include the plural and vice versa . All references to statutes and related regulations shall include any amendments of the same and any successor statutes and regulations. Except as expressly set forth herein, all references to any instruments or agreements, including, without limitation, references to any of the Creditor Agreements shall include any and all modifications or amendments thereto and any and all extensions or renewals thereof.

     2.  Covenants . Company and Subordinated Lender hereby covenant that until the Senior Indebtedness shall have been paid in full and satisfied in cash and the Loan Agreement

shall have been terminated, all in accordance with the terms of the Loan Agreement, each will comply with such of the following provisions as are applicable to it:

     2.1 Transfers . Subordinated Lender covenants to cause any transferee from it of any Subordinated Indebtedness, prior to acquiring such interest, to execute and deliver a counterpart of this Agreement to Bank.

     2.2 Subordination Provisions . To induce Bank to enter into the Loan Agreement, notwithstanding any other provision of the Subordinated Indebtedness to the contrary but subject to subsection 2.2(a), any Distribution with respect to the Subordinated Indebtedness is and shall be expressly junior and subordinated in right of payment to all amounts due and owing upon all Senior Indebtedness outstanding from time to time until such time as the Senior Indebtedness has been paid in full in cash and the Loan Agreement has been terminated.

     (a)  Payments . Company shall not make a Distribution on the Subordinated Indebtedness until such time as the Senior Indebtedness shall have been paid in full in cash and the Loan Agreement shall have been terminated; provided , however , so long as no Default or Event of Default shall have occurred and be continuing under the Senior Lending Agreements, Company may pay, and Subordinated Lender may receive, regularly scheduled payments of interest on, and principal at the stated (but not any accelerated) maturity of, the Subordinated Indebtedness as set forth on the date hereof in the Note Purchase Agreement and the Subordinated Note.

     Following the occurrence of an Event of Default under the Senior Lending Agreements and receipt by Subordinated Lender of written notice of such Event of Default from Bank (such notice, the “ Default Notice ”), Company shall not make a Distribution on the Subordinated Indebtedness and Subordinated Lender shall not be entitled to receive any such Distribution in respect of the Subordinated Indebtedness; provided , however , that notwithstanding the foregoing restriction, Company may pay, and Subordinated Lender shall be entitled to receive, any then due and payable (on a non-accelerated basis) interest payment with respect to the Subordinated Indebtedness on the earlier to occur of (x) the date on which all such Events of Default specified in the Default Notice shall have been cured or waived, or (y) in the case of an Event of Default other than with respect to the payment when due of any Senior Indebtedness, the expiration of a period of 180 days from delivery of the Default Notice. Nothing herein shall limit the accrual of deferred interest or default interest in accordance with the terms of the Subordinated Lending Agreements.

     (b)  Limitation on Acceleration . During any period described in Section 2.2 (a) hereof in which a Distribution is not permitted to be made on Subordinated Indebtedness, Subordinated Lender shall not be entitled to accelerate the maturity of the Subordinated Indebtedness, exercise any Secured Lender Remedies or commence any other action or proceeding to recover any amounts due or to become due with respect to Subordinated Indebtedness, provided , however , the foregoing limitation on acceleration or exercise of any remedies shall not be applicable following (x) the occurrence of an Insolvency Event or (y) following the maturity or acceleration of the Senior Indebtedness.

     (c)  Prior Payment of Senior Indebtedness in Bankruptcy, etc . In the event of any insolvency or bankruptcy proceedings relative to Company or Company’s property, or any receivership, liquidation, reorganization or other similar proceedings in connection therewith, or, in the event of any proceedings for voluntary liquidation, dissolution or other winding up of Company or distribution or marshalling of Company’s assets or any composition with creditors of Company, whether or not involving insolvency or bankruptcy, or if Company shall cease its operations, call a meeting of its creditors or no longer do business as a going concern (each individually or collectively, an “Insolvency Event”), then all Senior Indebtedness shall be paid in full and satisfied in cash and the Loan Agreement terminated before any Distribution shall be made on account of any Subordinated Indebtedness. Any such Distribution resulting from an Insolvency Event which would, but for the provisions hereof, be payable or deliverable in respect of the Subordinated Indebtedness, shall be paid or delivered directly to Bank until amounts owing upon Senior Indebtedness shall have been paid in full in cash and the Loan Agreement terminated provided that any such Distribution to Bank to which Subordinated Lender would be entitled except for the provisions of this Agreement shall, as between Company and Subordinated Lender, not be deemed to be a Distribution by Company to or on account of the Subordinated Indebtedness.

     (d)  Acceleration . In the event of all Senior Indebtedness becoming due and payable, whether by acceleration, maturity or otherwise, no Distribution shall thereafter be made on account of the Subordinated Indebtedness until all Senior Indebtedness shall be paid in full in cash and the Loan Agreement shall have been terminated.

     (e)  Power of Attorney . Subordinated Lender shall have the right to participate in any bankruptcy or insolvency proceedings, subject to the terms and conditions of this Section 2.2(e). To enable Bank to assert and enforce its rights hereunder upon the happening of any Insolvency Event and until all amounts owing upon Senior Indebtedness shall have been paid in full in cash and the Loan Agreement terminated, Bank or any person whom it may designate is hereby irrevocably appointed attorney in fact for Subordinated Lender with full power to act in the place and stead of Subordinated Lender solely for such purpose, including the right to make, present, file and vote such proofs of claim against Company on account of all or any part of the Subordinated Indebtedness as Bank may deem advisable and to receive and collect any and all distributions or other payments in respect of the Subordinated Indebtedness made thereon and to apply the same on account of the Senior Indebtedness. In the event that Bank or its designee fails to file a proof of claim with respect to the Subordinated Indebtedness in any bankruptcy proceeding relative to Company prior to the date which is ten (10) days prior to any claims bar date in such proceeding, Subordinated Lender may file such proofs of claim with respect to the Subordinated Indebtedness. Subordinated Lender will execute and deliver to Bank such instruments as may be required by Bank to enforce any and all Subordinated Indebtedness, to effectuate the aforesaid power of attorney and to effect collection of any and all distributions or other payments in respect of the Subordinated Indebtedness which may be made at any time after the occurrence of an Insolvency Event, on account thereof, and Subordinated Lender hereby irrevocably appoints Bank as the lawful attorney and agent of Subordinated Lender to execute financing statements on behalf of Subordinated Lender and hereby further authorizes Bank to file such financing statements in any appropriate public office.

     (f)  Knowledge; Delivery of Default Notice . Subordinated Lender shall not at any time be charged with knowledge of any Event of Default under the Senior Lending Agreements or on such account be prohibited from receiving or retaining any payment of monies or from taking any action regarding acceleration or the exercise of remedies, unless and until Subordinated Lender shall have received the Default Notice; provided , however , any “default” or “event of default” under the Subordinated Note and/or Subordinated Lending Agreements shall automatically constitute an Event of Default under the Senior Lending Agreements so that payments received by Subordinated Lender following any such occurrence shall not be retained irrespective of the lack of receipt by Subordinated Lender of a Default Notice, unless the Event of Default is waived by such Holder of Subordinated Indebtedness or satisfied or cured by Company.

     Each Default Notice shall be deemed to be properly given by Bank or other holder of Senior Indebtedness to Subordinated Lender if such Default Notice is delivered in accordance with Section 4.10 hereof.

     (g)  Payments Held in Trust . Should any Distribution or the proceeds thereof, in respect of the Subordinated Indebtedness, be collected or received by Subordinated Lender or any Affiliate (as such term is defined in Rule 405 of Regulation C adopted by the Securities and Exchange Commission pursuant to the Securities Act of 1933) of Subordinated Lender at a time when Subordinated Lender is not permitted to receive any such Distribution or proceeds thereof pursuant to the terms hereof, then Subordinated Lender will forthwith deliver, or cause to be delivered, the same to Bank in precisely the form held by Subordinated Lender (except for any necessary endorsement) and until so delivered, the same shall be held in trust by Subordinated Lender, or any such Affiliate, as the property of Bank and shall not be commingled with other property of Subordinated Lender or any such Affiliate.

     (h)  Subrogation . Subject to the prior payment in full in cash of the Senior Indebtedness and the termination of the Loan Agreement, to the extent that Bank has received any Distribution on the Senior Indebtedness which, but for this Agreement, would have been applied to the Subordinated Indebtedness, the rights of Subordinated Lender shall be subrogated to the then or thereafter rights of Bank including, without limitation, the right to receive any Distribution made on the Senior Indebtedness (as if the Senior Indebtedness had not been paid in full or the Loan Agreement terminated) until the principal of, interest on and other charges due under the Subordinated Indebtedness shall be paid in full; and, for the purposes of such subrogation, no Distribution to Bank to which the Subordinated Lender would be entitled except for the provisions of this Agreement shall, as between Company, its creditors (other than Ban