Exhibit 10.2

WARRANT AGREEMENT
 
WARRANT AGREEMENT dated as of June 7th, 2006 between North American Scientific,
Inc., a Delaware corporation (the “Company”), and Western Corporate Services dba
U.S. Stock Transfer Corporation, a California corporation (the “Warrant Agent”).

The Company proposes to issue stock purchase warrants (hereinafter called the
“Warrants”). Each Warrant entitles the holder thereof to purchase, within seven
(7) years from the offering date, one share of common stock, par value $0.01 per
share (the “Common Stock”), at a purchase price equal to $2.08 per share. The
Warrant Agent, at the request of the Company, has agreed to act as the agent of
the Company in connection with the issuance, registration, transfer, exchange,
and exercise of the Warrants.

NOW, THEREFORE, in consideration of the premises and mutual agreements herein
set forth:

SECTION 1. Appointment of Warrant Agent. The Company hereby appoints the Warrant
Agent to act as agent for the Company in accordance with the instructions
hereinafter set forth in this Agreement, and the Warrant Agent hereby accepts
such appointment. The Company may from time to time appoint such Co-Warrant
Agents as it may deem necessary or desirable. The Company shall promptly notify
the Warrant Agent from time to time in writing of the number of Warrants to be
issued and furnish written instructions in connection therewith.

SECTION 2. Form of Warrant Certificates. The Warrant Certificates (and the forms
of election to purchase shares and of assignment to be printed on the reverse
thereof) shall be substantially of the tenor and purport recited in Exhibit A
hereto and may have such letters, numbers or other marks of identification or
designation and such legends, summaries or endorsements printed, lithographed or
engraved thereon as the Company may deem appropriate and as are not inconsistent
with the provisions of this Warrant Agreement, or as may be required to comply
with any law or with any rule or regulation made pursuant thereto or with any
rule or regulation of any national security association and/or stock exchange on
which the Warrants may from time to time be listed or quoted, or to conform to
usage. The Warrant Certificates shall be dated as of the date of issuance
thereof by the Warrant Agent, either upon initial issuance or upon transfer or
exchange, and initially shall entitle the holders thereof to purchase one share
of Common Stock, but the number of such shares and the purchase price per share
of Common Stock shall be subject to adjustments as provided herein.

SECTION 3. Countersignature and Registration. The Warrant Certificates shall be
executed on behalf of the Company by the President and Chief Executive Officer
and the Chief Financial Officer, by facsimile signature, and shall be attested
by the Secretary of the Company by facsimile signature. The Warrant Certificates
shall be manually countersigned by the Warrant Agent and shall not be valid for
any purpose unless so countersigned. In case any officer of the Company who
shall have signed any of the Warrant Certificates shall cease to be such officer
of the Company before countersignature by the Warrant Agent and issuance and
delivery by the Company, such Warrant Certificates, nevertheless, may be
countersigned by the Warrant Agent, issued and delivered with the same force and
effect as though the person who signed such Warrant Certificates had not ceased
to be such officer of the Company; and any Warrant Certificates may be signed on
behalf of the Company by any person who, at the actual date of the execution of
such Warrant Certificates, shall be a proper officer of the Company to sign such
Warrant Certificates, although at the date of the execution of this Warrant
Agreement any such person was not such an officer.

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The Warrant Agent will keep or cause to be kept, at one of its offices in the
City of Glendale, State of California, books for registration and transfer of
the Warrant Certificates issued hereunder. Such books shall show the names and
addresses of the respective holders of the Warrant Certificates, the number of
Warrants evidenced on its face by each of the Warrant Certificates, and the date
of each of the Warrant Certificates.

The Warrant Agent shall countersign a Warrant Certificate only (a) upon initial
issuance of the Warrants in accordance with the written order signed by an
authorized officer of the Company or (b) upon exchange, transfer or substitution
for one or more previously countersigned Warrant Certificates as hereinafter
provided.

SECTION 4. Transfer and Exchange. Subject to Section 6 hereof, the Warrant Agent
shall, from time to time, register the transfer, in whole or in part, of any
outstanding Warrant Certificate upon the books to be maintained by the Warrant
Agent for that purpose, upon surrender thereof for transfer properly endorsed or
accompanied by appropriate instruments of transfer and written instructions for
transfer. Upon any such registration of transfer, a new Warrant Certificate
shall be issued to the transferee and the surrendered Warrant Certificate shall
be canceled by the Warrant Agent. Any Warrant Certificate may be exchanged at
the option of the holder thereof, upon surrender at the office of the Warrant
Agent specified in Section 21 hereof, for another Warrant Certificate, or other
Warrant Certificates of different denominations, representing in the aggregate
the right to purchase a like number of shares of Common Stock. No fractional
Warrant Certificates will be issued. The Company may require payment of a sum
sufficient to cover any tax or governmental charge that may be imposed in
connection with any transfer or exchange of Warrant Certificates.

SECTION 5. Warrant Common Stock. As hereinafter used in this Agreement, “Warrant
Common Stock” shall mean only Common Stock, and stock of any other class into
which such presently authorized Common Stock may hereafter be changed, issuable
upon exercise or exchange of the Warrant. In case, by reason of the operation of
Section 7, the Warrants shall entitle the registered holders thereof to purchase
any other shares of stock or other securities or property of the Company or of
any other corporation, any reference in this Agreement to the exercise of
Warrants shall be deemed to refer to and include the purchase of such other
shares of stock or other securities or property upon such exercise.

SECTION 6. Warrant Price and Stock Conversion Date of Warrants. The registered
holder of any Warrant Certificate may exercise or exchange the Warrants
evidenced thereby in whole or in part at any time 180 days after the date hereof
upon surrender of the Warrant Certificate with the form of election to purchase
on the reverse side thereof duly executed, to the Warrant Agent at the principal
office of the Warrant Agent in the City of Glendale, State of California,
together with payment of the purchase price for each share of Common Stock as to
which the Warrants are exercised, at or prior to 12:30 p.m. Pacific Time on June
6, 2013 (the “Exercise Date”).

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The purchase price for each share of Common Stock pursuant to the exercise of a
Warrant shall be equal to $2.08 per share (the “Warrant Price”), in each case as
adjusted pursuant to Section 7 hereof, and shall be payable in lawful money of
the United States of America.

SECTION 7. Warrant Adjustments. The Warrant Price and the number of shares
purchasable upon exercise of a Warrant shall be subject to adjustment as
follows:

(a) Stock Dividends, Subdivisions, Combinations and Reclassifications. In case
the Company shall at any time after the date of this Agreement (i) declare a
dividend on the Common Stock payable in shares of Common Stock, (ii) subdivide
the outstanding Common Stock, (iii) combine the outstanding Common Stock into a
smaller number of shares, or (iv) issue any shares of its capital stock in a
reorganization or reclassification of the Common Stock (including any such
reorganization or reclassification in connection with a consolidation or merger
in which the Company is the continuing corporation), the Warrant Price in effect
at the time of the record date for such dividend or of the effective date of
such subdivision, combination, reorganization or reclassification, and/or the
number and kind of shares of capital stock issuable upon exercise of the
Warrants on such date shall be proportionately adjusted so that the holder of
any Warrant exercised after such time shall be entitled to receive the aggregate
number and kind of shares of capital stock which, if such Warrant had been
exercised immediately prior to such date and at a time when the Common Stock
transfer books of the Company were open, such holder would have owned upon such
exercise and been entitled to receive by virtue of such dividend, subdivision,
combination, reorganization or reclassification. Such adjustment shall be made
successively whenever any event listed above shall occur.

(b) Rights Upon Distribution of Assets or Other Property. In case the Company
shall at any time after the date of this Agreement declare or make any dividend
or other distribution of its assets (or rights to acquire its assets) to holders
of shares of Common Stock, by way of return of capital or otherwise (including,
without limitation, any distribution of cash, stock or other securities not
addressed by Section 7(a), property or options not addressed by Section 7(a) by
way of a dividend, spin off, reclassification, corporate rearrangement, scheme
of arrangement or other similar transaction) (a “Distribution”), then, in each
such case:

(i) any Warrant Price in effect immediately prior to the close of business on
the record date fixed for the determination of holders of shares of Common Stock
entitled to receive the Distribution shall be reduced, effective as of the close
of business on such record date, to a price determined by multiplying such
Warrant Price by a fraction of which (i) the numerator shall be the Closing Bid
Price (as defined below) of a share of Common Stock on the trading day
immediately preceding such record date minus the value of the Distribution (as
determined in good faith by the Company’s Board of Directors) applicable to one
share of Common Stock, and (ii) the denominator shall be the Closing Bid Price
of the shares of Common Stock on the trading day immediately preceding such
record date; and

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(ii) the number of Warrant Shares shall be increased to a number of shares equal
to the number of shares of Common Stock obtainable immediately prior to the
close of business on the record date fixed for the determination of holders of
shares of Common Stock entitled to receive the Distribution multiplied by the
reciprocal of the fraction set forth in the immediately preceding paragraph
(ii); provided that in the event that the Distribution is of shares of common
stock (“Other Shares of Common Stock”) of a company whose common shares are
traded on a national securities exchange or a national automated quotation
system, then any holder of each Warrant may elect to receive a warrant to
purchase Other Shares of Common Stock in lieu of an increase in the number of
Warrant Shares, the terms of which shall be identical to those of this Agreement
and the Warrants, except that such warrant shall be exercisable into the number
of shares of Other Shares of Common Stock that would have been payable to the
holder of each Warrant pursuant to the Distribution had such holder exercised
its Warrant immediately prior to such record date and with an aggregate exercise
price equal to the product of the amount by which the exercise price of such
Warrant was decreased with respect to the Distribution pursuant to the terms of
the immediately preceding paragraph (i) and the number of Warrant Shares
calculated in accordance with the first part of this paragraph (ii).

(iii) As used above, “Closing Bid Price” means the last closing bid price for
the Common Stock on the Nasdaq National Market, as reported by Bloomberg
Financial Markets or its successor (“Bloomberg”), or, if the Nasdaq National
Market operates on an extended hours basis and does not designate the closing
bid price or the closing trade price, as the case may be, then the last bid
price of such security prior to 4:00:00 p.m., New York Time, as reported by
Bloomberg, or, if the Principal Market is not the principal securities exchange
or trading market for such security, the last closing bid price of such security
on the principal securities exchange or trading market where such security is
listed or traded as reported by Bloomberg, or if the foregoing do not apply, the
last closing bid price of such security in the over-the-counter market on the
electronic bulletin board for such security as reported by Bloomberg, or, if no
closing bid price is reported for such security by Bloomberg, the average of the
bid prices, or the ask prices, respectively, of any market makers for such
security as reported in the “pink sheets” by Pink Sheets LLC (formerly the
National Quotation Bureau, Inc.). If the Closing Bid Price cannot be calculated
on a particular date on any of the foregoing bases, the Closing Bid Price of
such security on such date shall be the fair market value as mutually determined
by the Company and the holder of the Warrant.

(c) Consolidation, Merger or Sale of Assets. If, prior to the exercise of any
Warrants, the Company shall at any time consolidate with or merge into another
corporation, the holder of any Warrants will thereafter receive, upon the
exercise thereof in accordance with the terms of this Agreement, the securities
or property to which the holder of the number of shares of Common Stock then
deliverable upon the exercise or conversion of such Warrants would have been
entitled upon such consolidation or merger, and the Company shall take such
steps in connection with such consolidation or merger as may be necessary to
assure that the provisions hereof shall thereafter be applicable, as nearly as
reasonably may be, in relation to any securities or property thereafter
deliverable upon the exercise of the Warrants. The Company or the successor
corporation, as the case may be, shall execute and deliver to the Warrant Agent
a supplemental agreement so providing, and the terms of any agreement pursuant
to which any such consolidatation or merger is effected shall include terms
requiring the Company or the successor corporation to comply with the provisions
of this subsection (c). A sale of all or substantially all the assets of the
Company for a consideration (apart from the assumption of obligations)
consisting primarily of securities shall be deemed a consolidation or merger for
the foregoing purposes. The provisions of this subsection (c) shall similarly
apply to successive mergers or consolidations or sales or other transfers.

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(d) Calculations to the Nearest Cent and One-Hundredth of a Share. No adjustment
in the Warrant Price shall be required unless such adjustment would require an
increase or decrease of at least 1% in such price; provided, however, that any
adjustments which by reason of this Section 7(d) are not required to be made
shall be carried forward and taken into account in any subsequent adjustment.
All calculations under this Section 7 shall be made to the nearest cent and to
the nearest one-hundredth of a share as the case may be. Notwithstanding the
first sentence of this subsection (d), any adjustment required by this Section 7
shall be made no later than the earlier of six months from the date of the
transaction which mandates such adjustment or the expiration of the right to
exercise any Warrant.

(e) Notice of Warrant Adjustment. Whenever the Warrant Price or the number of
shares purchasable upon exercise of a Warrant shall be adjusted as provided in
this Section 7, the Company shall forthwith file with the Warrant Agent a
certificate, signed by a firm of independent public accountants, showing in
detail the facts requiring such adjustment and the Warrant Price and number of
shares so purchasable that will be effective after such adjustment. The Company
shall also cause a notice setting forth any adjustments to be sent by mailing
first class, postage prepaid, to each registered holder of a Warrant or Warrants
at its address appearing on the Warrant register and, at its option, may cause a
copy of such notice to be published once in an English language newspaper of
general circulation in the City of New York, New York. The Warrant Agent shall
have no duty with respect to any certificate filed with it except to keep the
same on file and available for inspection by registered holders of Warrants
during reasonable business hours. The Warrant Agent shall not at any time be
under any duty or responsibility to any holder of a Warrant to determine whether
any facts exist which may require any adjustment of the Warrant Price, or with
respect to the nature of any adjustment of the Warrant Price when made, or with
respect to the method employed in making such adjustment.

(f) Other Notices. In case the Company after the date hereof shall propose to
take any action of the type described in subsections (a), (b) or (c) of this
Section 7, the Company shall file with the Warrant Agent a certificate, signed
by the President and Chief Executive Officer or the Chief Financial Officer of
the Company and by its Secretary or Assistant Secretary specifying, in the case
of any action of the type specified in subsections (a), (b) or (c), the date on
which such action shall take place and shall also set forth such facts with
respect thereto as shall be reasonably necessary to indicate the effect of such
action (to the extent such facts may be known on the date of such notice) on the
Warrant Price and the number, or kind, or class of shares or other securities or
property which shall be purchasable upon exercise of Warrants. The Company shall
also cause a notice setting forth any adjustments to be sent by mailing first
class, postage prepaid, to each registered holder of a Warrant Certificate or
Warrant Certificates at its address appearing on the Warrant register and, at
its option, may cause a copy of such notice to be published once in an English
language newspaper of general circulation in the City of New York, New York.
Failure to give such notice or any defect therein shall not affect the legality
or validity of such action.

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(g) No Change in Warrant Terms on Adjustment. Irrespective of any of the
adjustments in the Warrant Price or the number of shares of Warrant Common
Stock, Warrant Certificates theretofore or thereafter issued may continue to
express the same prices and number of shares as are stated in a similar Warrant
Certificate issuable initially, or at some subsequent time, pursuant to this
Agreement and such number of shares specified therein shall be deemed to have
been so adjusted.

(h) Treasury Shares. Shares of Common Stock at any time owned by the Company
shall not be deemed to be outstanding for purposes of any computation under this
Section 7.

(i) Optional Reduction in Warrant Price. Anything in this Section 7 to the
contrary notwithstanding, the Company shall be entitled to make such reductions
in the Warrant Price, in addition to those adjustments required by this Section
7, as it in its sole discretion shall determine to be necessary in order that
any (1) consolidation or subdivision of the Common Stock, (2) issuance wholly
for cash of any Common Stock at less than the Current Market Price, (3) issuance
wholly for cash of Common Stock or securities which by their terms are
convertible into or exchangeable for Common Stock, (4) stock dividend, or (5)
issuance of rights, options or warrants referred to hereinabove in this Section
7, hereinafter made by the Company to its common stockholders, shall not be
taxable to them.

The Company may, at its option, at any time during the term of the Warrants,
reduce the then current Warrant Price to any amount deemed appropriate by the
Board of Directors of the Company, for any length of time.
 
Other than with respect to clause (1) in Section7(i), the Warrant Price of the
Warrants shall not be reduced pursuant to this Section 7(i) below $1.89 (or such
lower Warrant Price as may be applicable as a result of prior adjustment(s)
under Section 7(a), (b) or (c)).

SECTION 8. Current Market Price. For all purposes of this Agreement, the Current
Market Price per share of Common Stock on any date shall be deemed to be the
average of the daily closing prices for the five consecutive business days
commencing before such date. The closing price for each day shall be the average
of the closing bid and asked prices, as reported by the Nasdaq National Market
or a similar source selected from time to time by the Company for the purpose.
If on any such date the shares of Common Stock are not quoted by any such
source, the fair value of such shares on such date, as determined by the Board
of Directors of the Company, shall be used.

SECTION 9. Exercise of Warrants. (a) Subject to the provisions of this
Agreement, each registered holder of Warrants shall have the right, which may be
exercised as in such Warrant Certificates expressed, to purchase from the
Company (and the Company shall issue and sell to such registered holders of
Warrants) all or part of the number of fully paid and nonassessable shares of
Warrant Common Stock specified in such Warrant Certificates (subject to the
adjustments as herein provided), upon surrender to the Company at the office of
the Warrant Agent specified in Section 21 hereof, of such Warrant Certificates
with the exercise form on the reverse thereof duly filled in and signed, and
upon payment to the Warrant Agent to the account of the Company of the Warrant
Price for the number of shares of Warrant Common Stock in respect of which such
Warrants are then exercised. The date of exercise of any Warrant shall be deemed
to be the date of its receipt by the Warrant Agent duly filled in and signed and
accompanied by proper funds as hereinafter provided. Payment of such Warrant
Price may be made in wire transfer in immediately available funds, cash, or by
certified or official bank check. No adjustment shall be made for any cash
dividends on shares of Warrant Common Stock issuable upon exercise of a Warrant.
Upon such surrender of Warrants, and payment of the Warrant Price as aforesaid,
the Company shall issue and cause to be delivered with all reasonable dispatch
to or upon the written order of the registered holder of such Warrants and in
such name or names as such registered holder may designate, a certificate or
certificates for the number of full shares of Warrant Common Stock so purchased
upon the exercise of such Warrants together with cash as provided in Section 11
of this Agreement, in respect of any fraction of a share of such stock issuable
upon such surrender.

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Each person in whose name any certificate for shares of Common Stock is issued
upon the exercise of Warrants shall for all purposes be deemed to have become
the holder of record of the Common Stock represented thereby on, and such
certificate shall be dated, the date upon which the Warrant Certificate
evidencing such Warrants was duly surrendered and payment of the Warrant Price
(and any applicable transfer taxes) was made; provided, however, that if the
date of such surrender and payment is a date upon which the Common Stock
transfer books of the Company are closed, such person shall be deemed to have
become the record holder of such shares on, and such certificate shall be dated,
the next succeeding business day on which the Common Stock transfer books of the
Company are open.

(b) In addition to the method of payment set forth in paragraph 9(a) and in lieu
of any cash payment required thereunder, each registered holder of the Warrants
shall have the right at any time and from time to time 180 days after the date
hereof to exercise the Warrant in full or in part by surrendering to the Company
at the office of the Warrant Agent specified in Section 21 hereof, such Warrant
Certificates with the exercise form on the reverse thereof duly filled in and
signed. The number of shares of Warrant Common Stock to be issued pursuant to
this paragraph (b) shall be equal to the difference between:

(i) the number of shares of Warrant Common Stock in respect of which the Warrant
Certificate is exercised; and

(ii) a fraction, the numerator of which shall be the number of shares of Common
Stock in respect of which the Warrant Certificate is exercised multiplied by the
Warrant Price and the denominator of which shall be the Current Market Price (as
defined in Section 8 hereof) of the Common Stock.

(c) 19.9% Limitations on Exercise of Warrants. Notwithstanding anything to the
contrary contained herein, the number of Warrant Shares that may be acquired by
a registered holder of Warrants upon any exercise of Warrants (or otherwise in
respect hereof) shall be limited to the extent necessary to insure that,
following such exercise (or other issuance), the total number of shares of
Common Stock then beneficially owned by such holder and its affiliates for
purposes of Section 13(d) of the Securities Exchange Act of 1934, as amended
(the “Exchange Act”) does not exceed 19.9% of the total number of issued and
outstanding shares of Common Stock as of the date of such exercise (including
for such purpose the shares of Common Stock issuable upon such exercise of
Warrants) unless Stockholder Approval has been obtained. “Stockholder Approval”
means the approval by a majority of the total votes cast on the proposal, in
person or by proxy, at a meeting of the stockholders of the Company held in
accordance with the Company’s by-laws, of a change of control in the Company, to
the extent required pursuant to Rule 4350(i) of the Nasdaq Stock Market, as
applicable. For such purposes, beneficial ownership shall be determined in
accordance with Section 13(d) of the Exchange Act and the rules and regulations
promulgated thereunder. This Section 9(c) may not be waived.

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SECTION 10. Unexercised Warrants. To the extent that any Warrant Certificates
remain outstanding at the expiration of the period during which the Warrants are
exercisable, the unexercised Warrants represented thereby shall be deemed null
and void.

SECTION 11. Elimination of Fractions. The Company shall not be required to issue
fractional shares of stock upon any exercise of Warrants. As to any final
fraction of a share which the same registered holder of one or more Warrants,
the rights under which are exercised in the same transaction or series of
related transactions, would otherwise be entitled to purchase upon such
exercise, the Company shall pay a cash adjustment in respect of such final
fraction in an amount equal to the same fraction of the Current Market Price (as
determined in the manner prescribed in Section 8 hereof) on the business day
which next precedes the day of exercise.

SECTION 12. Issue Taxes. The Company will pay documentary stamp taxes, if any,
attributable to the initial issuance of shares of Warrant Common Stock upon the
exercise of any Warrant; provided, however, that neither the Company nor the
Warrant Agent shall be required to pay any tax or taxes which may be payable in
respect of any transfer involved in the issue or delivery of any certificates
for shares of Warrant Common Stock in a name other than that of the registered
holder of Warrants, in respect of which such shares are initially issued.

SECTION 13. Reservation of Shares. The Company shall at all times reserve and
keep available out of its authorized but unissued stock, for the purpose of
effecting the issuance of stock upon exercise of Warrants, such number of shares
of its duly authorized Warrant Common Stock as shall from time to time be
sufficient to effect the issuance of shares of Warrant Common Stock upon
exercise of all Warrants at the time outstanding.

SECTION 14. Merger or Consolidation or Change of Name of Warrant Agent. Any
corporation into which the Warrant Agent may be merged or with which it may be
consolidated, or any corporation resulting from any merger or consolidation to
which the Warrant Agent shall be a party, or any corporation succeeding to the
corporate trust business of the Warrant Agent, shall be the successor to the
Warrant Agent hereunder without the execution or filing of any paper or any
further act on the part of any of the parties hereto, anything herein to the
contrary notwithstanding. In the case of Warrants which have been countersigned
by the Warrant Agent, but not delivered at the time any such successor to the
Warrant Agent succeeds to the agency created by this Agreement, any such
successor may adopt the countersignature of the original Warrant Agent and
deliver such Warrants so countersigned; and in case at that time any of the
Warrants shall not have been countersigned, any successor to the Warrant Agent
may countersign such Warrants either in the name of the predecessor Warrant
Agent or in the name of the successor Warrant Agent; and in all such cases such
Warrants shall have the full force and effect provided in the Warrants and in
this Agreement.

In case at any time the name of the Warrant Agent shall be changed and at such
time any of the Warrants shall have been countersigned but not delivered, the
Warrant Agent may adopt the countersignature under its prior name and deliver
Warrant Certificates so countersigned, and in case at that time any of the
Warrant Certificates shall not have been countersigned, the Warrant Agent may
countersign such Warrant Certificates either in its prior name or in its changed
name; and in all such cases such Warrant Certificates shall have the full force
and effect provided in the Warrant Certificates and in this Agreement.

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SECTION 15. Disposition of Proceeds on Exercise of Warrants, etc. The Warrant
Agent shall account promptly to the Company with respect to Warrants exercised
and concurrently pay to the Company all moneys received by the Warrant Agent for
the purchase of shares of Common Stock through the exercise of such Warrants.

The Warrant Agent shall keep copies of this Agreement available for inspection
by holders of Warrants during normal business hours at its office specified in
Section 21 hereof.

SECTION 16. Supplements and Amendments. The parties hereto may from time to time
supplement or amend this Agreement without the approval of any holders of
Warrants to cure any ambiguity or to correct or supplement any provision
contained in this Agreement which may be defective or inconsistent with any
other provision contained herein, or to make such other provisions with respect
to any change or any supplemental agreement as the parties may deem necessary or
desirable and which shall not materially adversely affect the interests of the
registered holders of the Warrants.

SECTION 17. Mutilated or Missing Warrant Certificates. If any Warrant shall be
mutilated, lost, stolen or destroyed the Warrant Agent shall deliver a new
Warrant Certificate of like tenor and denomination in exchange and substitution
therefor upon surrender and cancellation of the mutilated Warrant Certificate
or, in the case of a lost, stolen or destroyed Warrant Certificate, upon receipt
of evidence satisfactory to the Company and the Warrant Agent of the loss, theft
or destruction of such Warrant Certificate and, in either case, upon receipt of
such indemnity as the Company and the Warrant Agent may reasonably require.
Applicants for substitute Warrant Certificates shall also comply with such other
reasonable regulations and pay such other reasonable charges as the Warrant
Agent or the Company may prescribe. Any such new Warrant Certificate shall
constitute an original contractual obligation of the Company, whether or not the
allegedly lost, stolen, mutilated or destroyed Warrant Certificate shall be at
any time enforceable by anyone.

SECTION 18. Duties of the Warrant Agent. The Warrant Agent undertakes the duties
and obligations imposed by this Warrant Agreement upon the following terms and
conditions, by all of which the Company and the holders of Warrants, by their
acceptance thereof, shall be bound:

The Warrant Agent shall not be liable for or by reason of any of the statements
of fact or recitals contained in this Agreement or in the Warrant Certificates
(except its countersignature thereof and except such as describes the Warrant
Agent or action taken or to be taken by it) or be required to verify the same,
but all such statements and recitals are and shall be deemed to have been made
by the Company only. The Warrant Agent shall not be under any responsibility in
respect of the validity of this Agreement or the execution and delivery hereof
or in respect of the validity or execution of any Warrant Certificate (except
its countersignature thereof); nor shall it be responsible for any breach by the
Company of any covenant or condition contained in this Agreement or in any
Warrant Certificate to be complied with by the Company; nor shall it be
responsible for the making of any adjustment in the Warrant Price or the number
of shares issuable upon the exercise of a Warrant required under the provisions
of Section 7 or responsible for the manner, method or amount of any such change
or the ascertaining of the existence of facts that would require any such
change; nor shall it by any act hereunder be deemed to make any representation
or warranty as to the authorization or reservation of any shares to be issued
pursuant to this Agreement or any Warrant or as to whether any shares will, when
issued, be validly issued and fully paid and non-assessable.

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The Warrant Agent may execute and exercise any of the rights or powers hereby
vested in it or perform any duty hereunder either itself or by or through its
attorneys, agents or employees, and the Warrant Agent shall not be answerable or
accountable for any act, default, neglect or misconduct of any such attorneys,
agents or employees or for any loss to the Company resulting from such neglect
or misconduct, provided reasonable care had been exercised in the selection and
continued employment thereof.

The Warrant Agent may consult at any time with legal counsel satisfactory to it
(who may be legal counsel for the Company) and the advice of such counsel shall
be full and complete authorization and protection to the Warrant Agent as to any
action taken or omitted by it in good faith and in accordance with such advice.

The Warrant Agent shall incur no liability or responsibility to the Company or
to any holder of a Warrant Certificate for any action taken in reliance on any
notice, resolution, waiver, consent, order, certificate, or other paper,
document or instrument believed by it to be genuine and to have been signed,
sent or presented by the proper party or parties.

The Company agrees to pay to the Warrant Agent reasonable compensation for all
services rendered by the Warrant Agent in the execution of this Warrant
Agreement, to reimburse the Warrant Agent for all expenses (including reasonable
counsel fees), taxes and governmental charges and other charges of any kind and
nature incurred by the Warrant Agent in the execution of this Warrant Agreement
and to indemnify the Warrant Agent and save it harmless against any and all
liabilities, including judgments, costs and reasonable counsel fees, for
anything done or omitted by the Warrant Agent in the execution of this Warrant
Agreement except as a result of the Warrant Agent's negligence, willful
misconduct or bad faith.

The Warrant Agent and any stockholder, director, officer or employee of the
Warrant Agent may buy, sell, or deal in any of the Warrants or other securities
of the Company or become pecuniarily interested in any transaction in which the
Company may be interested, or contract with or lend money to the Company or
otherwise act as fully and freely as though it were not Warrant Agent under this
Warrant Agreement. Nothing herein shall preclude the Warrant Agent from acting
in any other capacity for the Company or for any other legal entity.

The Warrant Agent shall act hereunder solely as agent for the Company and in a
ministerial capacity, and its duties shall be determined solely by the
provisions hereof. The Warrant Agent shall not be liable for anything which it
may do or refrain from doing in connection with this Agreement except for its
own negligence, willful misconduct or bad faith.

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SECTION 19. Change of Warrant Agent. The Warrant Agent may resign and be
discharged from its duties under this Agreement upon 30 days’ notice in writing
mailed to the Company by registered or certified mail and the Company shall
subsequently mail such notice to the holders of the Warrant Certificates by
first-class mail. The Company may remove the Warrant Agent or any successor
Warrant Agent upon 30 days’ notice in writing, mailed to the Warrant Agent or
successor Warrant Agent, as the case may be, and to each transfer agent of the
Common Stock by registered or certified mail, and to the holders of the Warrant
Certificates by first-class mail. If the Warrant Agent shall resign or be
removed or shall otherwise become incapable of acting, the Company shall appoint
a successor to the Warrant Agent. If the Company shall fail to make such
appointment within a period of 30 days after such removal or after it has been
notified in writing of such resignation or incapacity by the resigning or
incapacitated Warrant Agent or by the holder of a Warrant Certificate (who
shall, with such notice, submit such holder's Warrant Certificate for inspection
by the Company), then the registered holder of any Warrant Certificate may apply
to any court of competent jurisdiction for the appointment of a new Warrant
Agent. Any successor Warrant Agent, whether appointed by the Company or by such
a court, shall be a corporation organized and doing business under the laws of
the United States or of the States of California or New York, in good standing,
having its principal office in the City of New York, New York or the City of Los
Angeles, California, which is authorized under such laws to exercise corporate
trust powers and is subject to supervision or examination by federal or state
authority and which has at the time of its appointment as Warrant Agent a
combined capital and surplus of at least $5,000,000. After appointment, the
successor Warrant Agent shall be vested with the same powers, rights, duties and
responsibilities as if it had been originally named as Warrant Agent without
further act or deed; but the predecessor Warrant Agent shall deliver and
transfer to the successor Warrant Agent any property at the time held by it
hereunder, and execute and deliver any further assurance, conveyance, act or
deed necessary for the purpose. Not later than the effective date of such
appointment the Company shall file notice thereof in writing with the
predecessor Warrant Agent and each transfer agent of the Common Stock, and mail
a notice thereof in writing to the registered holders of the Warrant
Certificates. Failure to give any notice provided for in this Section 19,
however, or any defect therein, shall not affect the legality or validity of the
resignation or removal of the Warrant Agent or the appointment of the successor
Warrant Agent, as the case may be.

SECTION 20. Identity of Transfer Agent. Forthwith upon the appointment of any
subsequent Transfer Agent for shares of the Common Stock, the Company will file
with the Warrant Agent a statement setting forth the name and address of such
Transfer Agent.

SECTION 21. Notices. Any notice pursuant to this Agreement to be given by the
Warrant Agent or by the registered holder of any Warrant to the Company shall be
sufficiently given if sent by first-class mail, postage prepaid, addressed
(until another address is filed in writing by the Company with the Warrant
Agent) as follows:

North American Scientific, Inc.
20200 Sunburst Street
Chatsworth, California 91311
Attention: David King
Telephone No.: (818) 734-8600
Telecopy No.: (818) 734-5224

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with a copy to:

Seyfarth Shaw LLP
55 East Monroe Street, Ste. 4200
Chicago, Illinois 60603
Attention: Allan Reich
Telephone No.: (312) 781-8650
Telecopy No.: (312) 269-8869

Any notice pursuant to this Agreement to be given by the Company or by the
registered holder of any Warrant to the Warrant Agent shall be sufficiently
given if sent by first-class mail, postage prepaid, addressed (until another
address is filed in writing by the Warrant Agent with the Company) as follows:

U.S. Stock Transfer Corporation
1745 Garden Avenue
Glendale, California
Attention: Syed Hussaini

SECTION 22. Successors. All the covenants and provisions of this Agreement by or
for the benefit of the Company or the Warrant Agent shall bind and inure to the
benefit of their respective successors and assigns hereunder.

SECTION 23. Governing Law. This Agreement and each Warrant issued hereunder
shall be deemed to be a contract made under the laws of the State of New York,
and for all purposes shall be construed in accordance with the laws of the State
of New York, without regard to principles of conflict of laws.

SECTION 24. Benefits of this Agreement. Nothing in this Agreement shall be
construed to give to any person or entity other than the Company, the Warrant
Agent and the registered holders of the Warrant Certificates any legal or
equitable right, remedy or claim under this Agreement; but this Agreement shall
be for the sole and exclusive benefit of the Company, the Warrant Agent and the
registered holders of the Warrant Certificates. This Warrant shall not entitle
the holder to any voting rights or any rights as a stockholder of the Company.
The rights and obligations of the Company, the Warrant Agent, the holder and any
holder of shares of Common Stock issuable hereunder shall survive the exercise
of this Warrant.

SECTION 25. Counterparts. This Agreement may be executed in any number of
counterparts and each of such counterparts shall for all purposes be deemed to
be an original, and all such counterparts shall together constitute but one and
the same instrument.

SECTION 26. Registration of Shares of Common Stock. The Company will furnish to
the Warrant Agent (i) if a registration statement filed under the Securities Act
of 1933, as amended, has been declared effective with respect to the shares
issuable upon exercise of the Warrant (the “Registration Statement”), within 10
days after the Registration Statement has been declared effective, an opinion of
counsel to the effect that a Registration Statement is then in effect with
respect to the Warrant Shares and the prospectuses hereinafter referred to
comply as to form in all material respects with the requirements of the
Securities Act of 1933, as amended, and the rules and regulations of the
Securities and Exchange Commission thereunder; or (ii) within 10 days of such
time as a Registration Statement with respect to the shares of Warrant Common
Stock issuable upon the exercise of the Warrants is not required under the
Securities Act of 1933, as amended, an opinion of counsel to the effect that a
Registration Statement is not required under the Securities Act of 1933, as
amended, and the rules and regulations of the Securities and Exchange Commission
thereunder. In the event that said opinion states that such a Registration
Statement is in effect, the Company will, within 10 days of after the
Registration Statement has been declared effective, furnish the Warrant Agent
with current prospectuses meeting the requirements of said Act and all rules and
regulations thereunder in sufficient quantity to permit the Warrant Agent to
deliver a prospectus to each transferee of a Warrant Certificate and each holder
of a Warrant Certificate upon exercise or conversion thereof. The Company
further agrees to pay all fees, costs and expenses in connection with the
preparation and delivery to the Warrant Agent of the foregoing opinions and
prospectuses.

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If any shares of Warrant Common Stock issuable upon the exercise of the Warrants
or the issuance thereof requires registration or approval of any governmental
authority, including, without limitation, the filing of necessary amendments,
supplements or post-effective amendments to a Registration Statement of the
Company under the Securities Act of 1933, or the taking of any other action
under the laws of the United States of America or any political subdivision
hereof or under the laws of any state of the United States of America before
such shares may be validly and legally issued, then the Company covenants that
it will in good faith and as expeditiously as possible endeavor to secure and
keep effective such registration or approval or to take such other action, as
the case may be.

SECTION 27. Entire Agreement. This Agreement (together with the Exhibits
attached hereto) and the Securities Purchase Agreements between certain
purchasers and the Company set forth the entire agreement of the Company and the
holder of the Common Stock issuable upon the exercise of this Warrant with
respect to the rights of the holder and the Common Stock issuable upon the
exercise of this Warrant.

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IN WITNESS WHEREOF, the parties hereto have caused this Warrant Agreement to be
executed and delivered as of the day and year first above written.
 

 
NORTH AMERICAN SCIENTIFIC, INC.

By:  __________________________
Name:
Title:

U.S. Stock Transfer Corporation
as Warrant Agent

By:  __________________________
Name:
Title:

 

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EXHIBIT A
Form of Warrant

EXERCISABLE AT ANY TIME AFTER DECEMBER 3, 2006 AND AT OR PRIOR TO 12:30 P.M.
PACIFIC TIME ON JUNE 6, 2013
 
WARRANT CERTIFICATE
NORTH AMERICAN SCIENTIFIC, INC.
 
No. W-
 

 
This certifies that _____________________________ or registered assigns is the
registered holder of the number of Warrants set forth above, and is entitled,
upon surrender of this Warrant Certificate at the office of U.S. Stock Transfer
Corporation, Warrant Agent (or any successor as such Warrant Agent), in the City
of Glendale, California, at any time 180 after the date hereof and at or prior
to 12:30 p.m. Pacific Time on June 6, 2013, to purchase one share of Common
Stock, par value $0.01, of North American Scientific, Inc., a Delaware
corporation (the “Company”), at the price equal to $2.08 per share.

The applicable per share purchase price shown above and the number of shares
issuable upon exercise of the Warrants represented by this Warrant Certificate
are subject to adjustment for the occurrence of certain events, including stock
dividends and split-ups, combinations, reorganizations, reclassifications,
consolidations, mergers or sales of properties and assets and upon the issuance
of certain rights or warrants to holders of Common Stock, as set forth in the
Warrant Agreement hereinafter referred to. A complete statement with respect to
such adjustments and to other terms and conditions pertaining to the Warrants is
contained in the Warrant Agreement, dated as of June 7, 2006, between the
Company and U.S. Stock Transfer Corporation, Warrant Agent, a copy of which may
be examined by the registered holder hereof at the office of the Warrant Agent.

To exercise the Warrants represented by this Warrant Certificate the form of
election to purchase on the reverse hereof must be duly executed and the
accompanying instructions for the registration and delivery of the stock must be
filled in.

The Warrants represented by this Warrant Certificate are transferable (subject
to the conditions set forth in the preceding paragraphs) at the office in the
City of Glendale, California of the Warrant Agent (or of its successor as
Warrant Agent) by the registered holder thereof in person or by attorney duly
authorized in writing, upon surrender of this Warrant Certificate. Upon any such
transfer, a new Warrant Certificate, representing the right to purchase a like
number of shares of the Company's Common Stock, will be issued to the transferee
in exchange for this Warrant Certificate.

This Warrant Certificate and similar Warrant Certificates when surrendered at
the office in the City of Glendale, California of the Warrant Agent (or of its
successor as Warrant Agent) by the registered holder hereof in person or by
attorney duly authorized in writing may be exchanged for another Warrant
Certificate or Warrant Certificates, representing in the aggregate the right to
purchase a like number of shares of the Company's Common Stock.

A-1

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If the Warrants evidenced by this Warrant Certificate remain outstanding at the
expiration of the period during which Warrants are exercisable, as set forth in
the first paragraph of this Warrant Certificate, such Warrants shall thereupon
be deemed null and void.

No fractional shares of Common Stock will be issued upon the exercise of any
Warrant or Warrants evidenced hereby, but in lieu thereof, a cash payment will
be made, as provided in the Warrant Agreement.

No holder of this Warrant Certificate shall be entitled to vote or receive
dividends or be deemed for any purpose the holder of Common Stock or of any
other securities of the Company which may at any time be issuable on the
exercise hereof, nor shall anything contained in the Warrant Agreement or herein
be construed to confer upon the holder hereof, as such, any of the rights of a
stockholder of the Company or any right to vote upon any matter submitted to
stockholders at any meeting thereof, or to give or withhold consent to any
corporate action (whether upon any recapitalization, issue of stock,
reclassification of stock, change of par value, consolidation, merger,
conveyance, or otherwise) or, except as provided in the Warrant Agreement, to
receive notice of meetings, or to receive dividends or subscription rights or
otherwise, until the Warrant or Warrants evidenced by this Warrant Certificate
shall have been exercised as provided in the Warrant Agreement.
 

 
NORTH AMERICAN SCIENTIFIC, INC.

By: __________________________
Its: __________________________

This Warrant Certificate is not valid until countersigned by the Warrant Agent.
 

Dated:
Countersigned:

___________________________,
as Warrant Agent,

By:_________________________
Authorized Officer

 
A-2

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FORM OF EXERCISE
(Form of exercise to be executed by the Warrant
Holder at the time of exercise)

To U.S. Stock Transfer Corporation or its successor as Warrant Agent:

The undersigned, holder of the within Warrant Certificate, hereby (1)
irrevocably exercises the undersigned's right to purchase _________ shares of
Common Stock, par value $0.01 per share, of North American Scientific, Inc. (the
“Company”) which the undersigned is entitled to purchase under the terms of the
within Warrant Certificate, or such other securities as the undersigned shall be
entitled to purchase under the terms of the Warrant Agreement referred to in
such Warrant Certificate by reason of the occurrence of certain events specified
therein, and (2) elects to make payment in full for the number of shares of
Common Stock so purchased by payment of $______ in wire transfer in immediately
available funds, cash or by certified or official bank check.

Please issue the certificate for shares of Common Stock in the name of, and pay
any cash for any fractional share to:

________________________________________________________________
Print or type name

________________________________________________________________
Social Security or other Identifying Number

________________________________________________________________
Street Address

________________________________________________________________
City             State             Zip Code

If such number of shares shall not be all the shares purchasable upon the
exercise of the Warrants evidenced by this Warrant Certificate, a new Warrant
Certificate for the balance of such Warrants remaining unexercised shall be
registered in the name of and delivered to:

Please insert social security or other identifying number: ___________________

_______________________________________________________________
(Please print name and address)

_________________________________________________________________

Dated: ___________, _______     ___________________________________
Signature
(Signature must conform in all respects to name of holder
as specified on the face of the Warrant Certificate)

A-3

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(Signature Medallion Guaranteed): ___________________________  Date:
___________________

(If the Common Stock, cash in lieu of fractional shares, or Warrants for any
unexercised balance are to be issued or paid to a person other than the person
in whose name the within Warrant is registered, or if otherwise requested by the
Company or the Warrant Agent, a signature Medallion guarantee is required.)
 
A-4

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ASSIGNMENT
(Form of assignment to be executed if Warrant
Holder desires to transfer Warrant)

FOR VALUE RECEIVED, __________________________________ hereby sells, assigns,
and transfer unto ____________________ this Warrant Certificate together with
all right, title or interest therein and does hereby irrevocably appoint
___________________ attorney to transfer the within Warrant Certificate on the
books of the Warrant Agent with full power of substitution in the premises.
 

 

Dated: _____________ _____________________________________   
Signature
(Signature must conform in all respects to name of holder as specified on the
face of the Warrant Certificate)

 
(Signature Medallion Guaranteed): ___________________________  Date:
___________________

A-5

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