FIRST LIEN PLEDGE AND SECURITY AGREEMENT

Exhibit 10.5

FIRST LIEN PLEDGE AND SECURITY AGREEMENT

made by

GLOBAL MONITORING SYSTEMS, INC.

in favor of

AMERICAN CAPITAL FINANCIAL SERVICES, INC.,

as First Lien Agent

Dated as of January 1, 2006

First Lien Pledge and Security Agreement

FIRST LIEN PLEDGE AND SECURITY AGREEMENT

                THIS FIRST LIEN PLEDGE AND SECURITY AGREEMENT (this “ Agreement ”) dated as of, made by Global Monitoring Systems, Inc., a Delaware corporation (the “ Grantor ”), in favor of American Capital Financial Services, Inc., a Delaware corporation (“ ACFS ”), as administrative and collateral agent for the Secured Parties (as defined herein) (in such capacity, the “ First Lien Agent ”).

RECITALS:

               A. Reference is made to the guarantees dated as of the date hereof, made (i) by Grantor in favor of ACFS with respect to the debt obligations of Global Dosimetry Solutions, Inc. (“ GDS ”) (the “ GDS Guaranty ”); (ii) by Grantor in favor of ACFS with respect to the debt obligations of Dosimetry Acquisitions (U.S.), LLC (“ Dosimetry ”) and Grantor (the “ Dosimetry Guaranty ”), and (iii) by Grantor in favor of ACFS with respect to the debt obligations of IST Acquisitions, Inc. (“ IST ,” and together with GDS and Dosimetry, the “ Borrowers ”) and Parent (the “ IST Guaranty ,” and together with the Dosimetry Guaranty and the GDS Guaranty, the “ Guarantees ”). Capitalized terms used in this Agreement and not otherwise defined herein have the meanings specified in the GDS Guaranty.

               B. Pursuant to the Guarantees, the Grantor has agreed to guaranty the payment and performance of the obligations of each of the Borrowers under their respective debt instruments.

               C. In order to secure its performance of the Guarantees, the Grantor has agreed to grant to First Lien Agent, as collateral agent for the Secured Parties, a Lien on and security interest in all of the Grantor’s assets and properties, whether now or hereafter existing, owned or acquired, all pursuant to the terms of this Agreement.

               NOW, THEREFORE, for and in consideration of the covenants and provisions set forth herein, and for other valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the Grantor agrees as follows:

SECTION 1. DEFINED TERMS

          1.1 Definitions . The following terms used herein shall have the meanings as defined in the Maryland UCC: Accounts, Certificated Security, Chattel Paper, Commercial Tort Claims, Documents, Equipment, Farm Products, General Intangibles, Goods, Instruments, Inventory, Letter-of-Credit Rights and Supporting Obligations.

               The following terms shall have the following meanings:

          “ Agreement ” means this First Lien Pledge and Security Agreement, as the same may be amended, supplemented or otherwise modified from time to time.

          “ Collateral ” has the meaning assigned to such term in Section 2.

          “ Collateral Account ” means any deposit account established by the First Lien Agent as provided in Section 5.1.

          “ Copyrights ” means (a) all copyrights arising under the laws of the United States, any other country or any political subdivision thereof, whether registered or unregistered and whether published or unpublished (including, without limitation, those listed in Schedule 5) , all registrations and recordings thereof, and all applications in connection therewith, including, without limitation, all registrations, recordings and applications in the United States Copyright Office, and (b) the right to obtain all renewals thereof.

          “ Copyright Licenses ” means any written agreement naming the Grantor as licensor or licensee (including, without limitation, those listed in Schedule 5) , granting any right under any Copyright, including, without limitation, the grant of rights to manufacture, distribute, exploit and sell materials derived from any Copyright.

          “ Deposit Account ” means “deposit account” as such term is defined in the Uniform Commercial Code of any applicable jurisdiction and, in any event, including, without limitation, any demand, time, savings, passbook or like account maintained with a depositary institution.

          “ Excluded Assets ” the collective reference to (i) any contract, General Intangible, Copyright License, Patent License or Trademark License (“ Intangible Assets ”), in each case to the extent the grant by the relevant Grantor of a security interest pursuant to this Agreement in the Grantor’s right, title and interest in such Intangible Asset (A) is prohibited by legally enforceable provisions of any contract, agreement, instrument or indenture governing such Intangible Asset, (B) would give any other party to such contract, agreement, instrument or indenture a legally enforceable right to terminate its obligations thereunder or (C) is permitted only with the consent of another party, if the requirement to obtain such consent is legally enforceable and such consent has not been obtained; provided , that in any event any Receivable or any money or other amounts due or to become due under any such contract, agreement, instrument or indenture shall not be Excluded Assets to the extent that any of the foregoing is (or if it contained a provision limiting the transferability or pledge thereof would be) subject to Section 9-406 of the Maryland UCC, and (ii) Foreign Subsidiary Voting Stock excluded from the definition of “Pledged Stock” set forth in this Section 1.1.

          “ Event of Default ” means an event of default under any of the Guaranteed Obligations.

          “ Foreign Subsidiary ” means any Subsidiary organized under the laws of any jurisdiction outside the United States of America.

          “ Foreign Subsidiary Voting Stock ” means the voting Capital Stock of any Foreign Subsidiary.

          “ Grantor Obligations ” means with respect to the Grantor, the collective reference to all obligations and liabilities of the Grantor which may arise under or in connection with this Agreement (including, without limitation, Section 2), the Guarantees, in each case whether on account of guarantee obligations, reimbursement obligations, fees, indemnities, costs, expenses or otherwise (including, without limitation, all fees and disbursements of counsel to the First

Lien Agent or to any Secured Party that are required to be paid by the Grantor pursuant to the terms of this Agreement).

          “ Guaranteed Obligations ” means the collective reference to (i) the obligations of the Grantor under the Guarantees and (ii) all other obligations and liabilities of the Grantors, whether direct or indirect, absolute or contingent, due or to become due, or now existing or hereafter incurred, which may arise under, out of, or in connection with, this Agreement (including, without limitation, all fees and disbursements of counsel to the First Lien Agent or to the Secured Parties that are required to be paid by the Grantor pursuant to the terms of this Agreement).

          “ Intellectual Property ” means the collective reference to all rights, priorities and privileges relating to intellectual property, whether arising under United States, multinational or foreign laws or otherwise, including, without limitation, the Copyrights, the Copyright Licenses, the Patents, the Patent Licenses, the Trademarks and the Trademark Licenses, and all rights to sue at law or in equity for any infringement or other impairment thereof, including the right to receive all proceeds and damages therefrom.

          “ Intercompany Note ” means any promissory note evidencing loans made by Grantor to any parent entity or any of its subsidiaries.

          “ Investment Property ” means the collective reference to (i) all “investment property” as such term is defined in Section 9-102(a)(49) of the Maryland UCC (other than any Foreign Subsidiary Voting Stock excluded from the definition of “Pledged Stock” in this Section 1.1) and (ii) whether or not constituting “investment property” as so defined, all Pledged Notes and all Pledged Stock.

          “ Issuers ” means the collective reference to each issuer of any Investment Property.

          “ Maryland UCC ” means the Uniform Commercial Code as from time to time in effect in the State of Maryland.

          “ Patents ” means (i) all letters patent of the United States, any other country or any political subdivision thereof, all reissues and extensions thereof and all goodwill associated therewith, including, without limitation, any of the foregoing referred to in Schedule 5 , (ii) all applications for letters patent of the United States or any other country and all divisions, continuations and continuations-in-part thereof, including, without limitation, any of the foregoing referred to in Schedule 5 , and (iii) all rights to obtain any reissues or extensions of the foregoing.

          “ Patent License ” means all agreements, whether written or oral, providing for the grant by or to the Grantor of any right to manufacture, use or sell any invention covered in whole or in part by a Patent, including, without limitation, any of the foregoing referred to in Schedule 5 .

          “ Pledged Collateral ” has the meaning assigned to such term in Section 2.2(a).

          “ Pledged Interests ” means the limited liability company interests listed on Schedule 1 , together with any other certificates, options or rights of any nature whatsoever in respect of the

limited liability company interests of any Person that may be issued or granted to, or held by, the Grantor while this Agreement is in effect.

          “ Pledged Notes ” means all promissory notes listed on Schedule 1 , all Intercompany Notes at any time issued to the Grantor and all other promissory notes issued to or held by the Grantor (other than promissory notes issued in connection with extensions of trade credit by the Grantor in the ordinary course of business).

          “ Pledged Securities ” means the collective reference to the Pledged Interests, Pledged Notes and the Pledged Stock.

          “ Pledged Stock ” means the shares of Capital Stock listed on Schedule 1 , together with any other shares, stock certificates, options or rights of any nature whatsoever in respect of the Capital Stock of any Person that may be issued or granted to, or held by, the Grantor while this Agreement is in effect; provided that in no event shall more than 65% of the total outstanding Foreign Subsidiary Voting Stock of any Foreign Subsidiary be required to be pledged hereunder.

          “ Proceeds ” means all “proceeds” as such term is defined in Section 9-102(a)(64) of the Maryland UCC on the date hereof and, in any event, including, without limitation, all dividends or other income from the Investment Property, collections thereon or distributions or payments with respect thereto.

          “ Receivable ” means any right to payment for goods sold, leased, licensed, assigned or otherwise disposed of, or for services rendered, whether or not such right is evidenced by an Instrument or Chattel Paper and whether or not it has been earned by performance (including, without limitation, any Account).

          “ Secured Parties ” means the First Lien Agent and its successors and assigns.

          “ Security Interest ” has the meaning assigned to such term in Section 2.

          “ Securities Act ” means the Securities Act of 1933, as amended.

          “ Trademarks ” means (i) all trademarks, trade names, corporate names, company names, business names, fictitious business names, trade styles, service marks, logos and other source or business identifiers, and all goodwill associated therewith, now existing or hereafter adopted or acquired, all registrations and recordings thereof, and all applications in connection therewith, whether in the United States Patent and Trademark Office or in any similar office or agency of the United States, any State thereof or any other country or any political subdivision thereof, or otherwise, and all common-law rights related thereto, including, without limitation, any of the foregoing referred to in Schedule 5 , and (ii) the right to obtain all renewals thereof.

          “ Trademark License ” means any agreement, whether written or oral, providing for the grant by or to the Grantor of any right to use any Trademark, including, without limitation, any of the foregoing referred to in Schedule 5 .

          1.2 Other Definitional Provisions . The words “hereof,” “herein,” “hereto” and “hereunder” and words of similar import when used in this Agreement shall refer to this

Agreement as a whole and not to any particular provision of this Agreement, and Section and Schedule references are to this Agreement unless otherwise specified.

          The meanings given to terms defined herein shall be equally applicable to both the singular and plural forms of such terms.

          Where the context requires, terms relating to the Collateral or any part thereof, when used in relation to a Grantor, shall refer to the Grantor’s Collateral or the relevant part thereof.

SECTION 2. GRANT OF SECURITY INTEREST

          2.1 Security Interest in Personal Property . The Grantor hereby mortgages, pledges, hypothecates, assigns and transfers to the First Lien Agent, and hereby grants to the First Lien Agent, its successors and assigns, for the ratable benefit of the Secured Parties, a lien on and a continuing security interest (the “ Security Interest ”), in all of the following property now owned or at any time hereafter acquired by the Grantor or in which the Grantor now has or at any time in the future may acquire any right, title or interest (collectively, the “ Collateral ”), as collateral security for the prompt and complete payment and performance when due (whether at the stated maturity, by acceleration or otherwise) of the Grantor Obligations:

          (n) all Goods and personal property not otherwise described above whether tangible or intangible and wherever located;

          (o) all books and records pertaining to the Collateral;

          (p) to the extent not otherwise included, all Proceeds and products of any and all of the foregoing, all Supporting Obligations in respect of any of the foregoing and all collateral security and guarantees given by any Person with respect to any of the foregoing; and

          (q) all property of the Grantor held by the First Lien Agent or any other Secured Party, including all property of every description, in the possession or custody of or in transit to the First Lien Agent or such Secured Party for any purpose, including safekeeping, collection or pledge, for the account of the Grantor or as to which the Grantor may have any right or power;

provided , that the Collateral shall not include any Excluded Assets or any leasehold interest of the Grantor.

          2.2 Pledge of Pledged Collateral .

          (a) The Grantor hereby assigns and pledges to the First Lien Agent, its successors and assigns, for the ratable benefit of the Secured Parties, a security interest in, all of the Grantor’s right, title and interest in, to and under (i) the Pledged Securities; (ii) subject to Section 5.3, all payments of dividends, cash, instruments and other property from time to time received, receivable or otherwise distributed in respect of, in exchange for or upon conversion of, and all other Proceeds received in respect of the Pledged Securities; (iii) subject to Section 5.3, all rights and privileges of the Grantor with respect to the securities and other property referred to in clauses (i) and (ii) above; and (iv) all Proceeds of any of the foregoing (the items in clauses (i) through (iv) above being collectively referred to as the “ Pledged Collateral ”);

          (b) The Grantor agrees to promptly deliver or cause to be delivered to First Lien Agent any and all Pledged Stock. Upon delivery to the First Lien Agent, (i) any Pledged Stock shall be accompanied by stock powers duly executed in blank or other instruments of transfer satisfactory to First Lien Agent and by such other instruments and documents as the First Lien Agent may reasonably request and (ii) all other property comprising part of the Pledged Collateral shall be accompanied by proper instruments of assignment duly executed by the applicable Grantor and such other instruments or documents as First Lien Agent may reasonably request. Each delivery of Pledged Stock shall be accompanied by a schedule describing the securities, which schedule shall be attached hereto as Schedule 1 and made a part hereof; provided that the failure to attach any such schedule hereto shall not affect the validity of such pledge of such Pledged Collateral. Each schedule so delivered shall supplement any prior schedules so delivered.

          2.3 It being understood that the Security Interest is granted as security only and shall not subject the First Lien Agent or any other Secured Party to, or in any way alter or modify, any obligation or liability of the Grantor with respect to or arising out of the Collateral.

SECTION 3. REPRESENTATIONS AND WARRANTIES

          3.1 Title; No Other Liens . The Grantor owns each item of the Collateral free and clear of any and all Liens or claims of others. No financing statement or other public notice with respect to all or any part of the Collateral is on file or of record in any public office, except such as have been filed in favor of the First Lien Agent, for the ratable benefit of the Secured Parties, pursuant to this Agreement. It is understood and agreed that the Grantor may, as part of its business, grant licenses to third parties to use Intellectual Property owned or developed by the Grantor. For purposes of this Agreement and the other Transaction Documents, such licensing activity shall not constitute a “Lien” on such Intellectual Property. Each of the First Lien Agent and each Secured Party understands that any such licenses may be exclusive to the applicable licensees, and such exclusivity provisions may limit the ability of the First Lien Agent to utilize, sell, lease or transfer the related Intellectual Property or otherwise realize value from such Intellectual Property pursuant hereto.

          3.2 Perfected First Priority Liens . The security interests granted pursuant to this Agreement (a) will constitute valid perfected security interests in all of the Collateral in favor of the First Lien Agent, for the ratable benefit of the Secured Parties, as collateral security for the Grantor’s Obligations, enforceable in accordance with the terms hereof against all creditors of the Grantor and any Persons purporting to purchase any Collateral from the Grantor and (b) except as aforesaid, are prior to all other Liens on the Collateral in existence on the date hereof.

          3.3 Jurisdiction of Organization; Chief Executive Office . On the date hereof, the Grantor’s jurisdiction of organization, identification number from the jurisdiction of organization (if any), and the location of the Grantor’s chief executive office or sole place of business or principal residence, as the case may be, are specified on Schedule 2 . The Grantor has furnished to the First Lien Agent a certified charter, certificate of incorporation or other organization document and good standing certificate as of a date which is recent to the date hereof.

          3.4 Inventory and Equipment . On the date hereof, the Inventory and the Equipment (other than mobile goods) are kept at the locations listed on Schedule 3 .

          3.5 Farm Products . None of the Collateral constitutes, or is the Proceeds of, Farm Products.

          3.6 Investment Property .

          (a) The shares of Pledged Stock pledged by the Grantor hereunder constitute all the issued and outstanding shares of all classes of the Capital Stock of each Issuer owned by the Grantor or, in the case of Foreign Subsidiary Voting Stock, if less, 65% of the outstanding Foreign Subsidiary Voting Stock of each relevant Issuer.

          (b) All the shares of the Pledged Stock have been duly and validly issued and are fully paid and nonassessable.

          (c) The Pledged Interests constitute all the issued and outstanding limited liability company interests of each Issuer owned by the Grantor.

          (d) Each of the Pledged Notes constitutes the legal, valid and binding obligation of the obligor with respect thereto, enforceable in accordance with its terms, subject

to the effects of bankruptcy, insolvency, fraudulent conveyance, reorganization, moratorium and other similar laws relating to or affecting creditors’ rights generally, general equitable principles (whether considered in a proceeding in equity or at law) and an implied covenant of good faith and fair dealing.

          (e) Schedule 1 correctly sets forth the percentage of the issued and outstanding shares of each class of Capital Stock of the Issuer thereof represented by such Pledged Stock.

          (f) The Grantor is the record and beneficial owner of, and has good and marketable title to, the Investment Property pledged by it hereunder, free of any and all Liens or options in favor of, or claims of, any other Person.

          (g) By virtue of the execution and delivery by the Grantor of this Agreement, when any Pledged Stock is delivered to the First Lien Agent in accordance with this Agreement, the First Lien Agent will obtain a legal, valid and perfected first priority lien upon and security interest in such Pledged Stock as security for the payment and performance of the Obligations; and

          (h) The pledge affected hereby is effective to vest in the First Lien Agent, for the benefit of the Secured Parties, the rights of the First Lien Agent in the Pledged Collateral as set forth herein.

          3.7 Receivables .

          (a) No material amount payable to the Grantor under or in connection with any Receivable is evidenced by any Instrument or Chattel Paper which has not been delivered to the First Lien Agent to the extent required by Section 4.2.

          (b) The amounts represented by the Grantor to the Secured Parties from time to time as owing to the Grantor in respect of the Receivables will at such times be accurate in all material respects.

          3.8 Intellectual Property.

          (a) On the date hereof, all material Intellectual Property of the Grantor described on Schedule 4 is valid, subsisting, unexpired and enforceable in accordance with its terms and applicable law, has not been abandoned and to Grantor’s knowledge, does not infringe the intellectual property rights of any other Person, except as would not be reasonably expected to have a Material Adverse Effect.

          (b) Except as set forth in Schedule 4 , on the date hereof, none of the Intellectual Property is the subject of any licensing or franchise agreement pursuant to which the Grantor is the licensor or franchisor, except as would not be reasonably expected to have a Material Adverse Effect.

          (c) No holding, decision or judgment has been rendered by any Governmental Authority which would limit, cancel or question the validity of, or the Grantor’s rights in, any

Intellectual Property in any respect that could reasonably be expected to have a Material Adverse Effect

          (d) No action or proceeding is pending, or, to the knowledge of the Grantor, threatened, on the date hereof which, if adversely determined, would have a Material Adverse Effect.

SECTION 4. COVENANTS

               The Grantor covenants and agrees with the First Lien Agent that, from and after the date of this Agreement until the Guaranteed Obligations shall have been paid in full:

          4.1 Delivery of Instruments and Chattel Paper . If any amount payable under or in connection with any of the Collateral shall be or become evidenced by any Instrument, Certificated Security or Chattel Paper, such Instrument, Certificated Security or Chattel Paper shall be immediately delivered to the First Lien Agent, duly indorsed in a manner satisfactory to the First Lien Agent, to be held as Collateral pursuant to this Agreement; provided that the Grantor shall not be obligated to deliver to the First Lien Agent any Instruments or Chattel Paper held by the Grantor at any time to the extent that the aggregate face amount of all such Instruments and Chattel Paper held by the Grantor at such time does not exceed $100,000.

          4.2 Maintenance of Insurance .

          (a) The Grantor will maintain, with financially sound and reputable companies, insurance policies (i) insuring the Inventory and Equipment against loss by fire, explosion, theft and such other casualties as may be reasonably satisfactory to the First Lien Agent and (ii) insuring the Grantor, the First Lien Agent and the Secured Parties against liability for personal injury and property damage relating to such Inventory and Equipment, such policies to be in such form and amounts and having such coverage as may be reasonably satisfactory to the First Lien Agent and the Lenders.

          (b) All such insurance shall (i) provide that no cancellation, material reduction in amount or material change in coverage thereof shall be effective until at least 30 days after receipt by the First Lien Agent of written notice thereof, (ii) name the First Lien Agent as insured party or loss payee, (iii) if reasonably requested by the First Lien Agent, include a breach of warranty clause and (iv) be reasonably satisfactory in all other respects to the First Lien Agent.

          4.3 Payment of Obligations . The Grantor will pay and discharge or otherwise satisfy at or before maturity or before they become delinquent, as the case may be, all taxes, assessments and governmental charges or levies imposed upon the Collateral or in respect of income or profits therefrom, as well as all claims of any kind (including, without limitation, claims for labor, materials and supplies) against or with respect to the Collateral, except that no such charge need be paid if the amount or validity thereof is currently being contested in good faith by appropriate proceedings, reserves in conformity with GAAP with respect thereto have been provided on the books of the Grantor and such proceedings could not reasonably be expected to result in the sale, forfeiture or loss of any material portion of the Collateral or any interest therein.

          4.4 Maintenance of Perfected Security Interest; Further Documentation .

          (a) The Grantor shall maintain the security interest created by this Agreement as a perfected security interest having at least the priority described in Section 3.2 and shall defend such security interest against the claims and demands of all Persons whomsoever.

          (b) The Grantor will furnish to the First Lien Agent from time to time statements and schedules further identifying and describing the assets and property of the Grantor and such other reports in connection with the Collateral as the First Lien Agent may reasonably request, all in reasonable detail.

          (c) At any time and from time to time, upon the written request of the First Lien Agent, and at the sole expense of the Grantor, the Grantor will promptly and duly execute and deliver, and have recorded, such further instruments and documents and take such further actions as the First Lien Agent may reasonably request for the purpose of obtaining or preserving the full benefits of this Agreement and of the rights and powers herein granted, including, without limitation, (i) the filing of any financing or continuation statements under the Uniform Commercial Code (or other similar laws) in effect in any jurisdiction with respect to the Security Interests and (ii) in the case of Investment Property, Deposit Accounts and Letter of Credit Rights, taking any actions necessary to enable the First Lien Agent to obtain “control” (within the meaning of the applicable Uniform Commercial Code) with respect thereto.

          (d) The Grantor shall have possession of the Collateral, except where as expressly otherwise provided in this Agreement or where the First Lien Agent chooses to perfect its security interest by possession in addition to the filing of a financing statement and other filing or recording documents or instruments with respect to the Collateral.

          (e) Except for statutory landlord liens regarding existing leases entered into by the Grantor, the Grantor agrees that it shall not permit any Collateral to be in the possession or control of any warehouseman, bailee, agent, landlord or processor at any time unless such warehouseman, bailee, agent, landlord or processor shall have been notified of the Security Interest and shall have acknowledged in writing, in form and substance satisfactory to the First Lien Agent, that such warehouseman, bailee, agent, landlord or processor holds the Collateral for the benefit of the First Lien Agent subject to the Security Interest and shall act upon the instructions of the First Lien Agent without further consent from the Grantor, and that such warehouseman, bailee, agent, landlord or processor further agrees to waive and release any Lien held by it with respect to such Collateral, whether arising by operation of law or otherwise.

          4.5 Changes in Name, etc. The Grantor will not, except upon 10 days’ prior written notice to the First Lien Agent and delivery to the First Lien Agent of all additional executed financing statements and other documents reasonably requested by the First Lien Agent to maintain the validity, perfection and priority of the Security Interest:

          (a) change its jurisdiction of organization or the location of its chief executive office or sole place of business or principal residence from that referred to in Section 3.3; or

          (b) change its name.

          4.6 Notices . The Grantor will advise the First Lien Agent and the Lenders promptly, in reasonable detail, of:

          (a) any Lien (other than security interests created hereby) on any of the Collateral which would adversely affect the ability of the First Lien Agent to exercise any of its remedies hereunder; and

          (b) the occurrence of any other event which could reasonably be expected to have a material adverse effect on the aggregate value of the Collateral or on the Security Interest.

          4.7 Investment Property .

          (a) If the Grantor shall become entitled to receive or shall receive any certificate (including, without limitation, any certificate representing a dividend or a distribution in connection with any reclassification, increase or reduction of capital or any certificate issued in connection with any reorganization), option or rights in respect of the Capital Stock of any Issuer, whether in addition