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                                                                      Exhibit 10


                                    HIE, INC.
                     NON-EMPLOYEE DIRECTOR STOCK OPTION PLAN

                   (amended and restated as of April 20, 1999)

         1.       Purpose of the Plan. The purpose of the HIE, Inc. Non-Employee
Director Stock Option Plan (the "Plan") of HIE, Inc. (the "Corporation") is to
promote the interests of the Corporation and its shareholders in obtaining and
maintaining the services of knowledgeable and independent directors on the
Corporation's Board of Directors (the "Board"). The Plan is intended to make
available for purchase by Non-Employee directors shares of the Corporation's
common stock, par value $.01 per share, together with associated preferred stock
purchase rights (the "Common Stock"), thus providing an additional incentive for
such directors to continue to serve on the Board and giving them a greater
interest as shareholders in the success of the Corporation.

         2.       Effective Date of the Plan. The Plan shall take effect on the
date of its adoption by the Board (the "Effective Date"), provided that the Plan
shall be subject to approval by the Corporation's shareholders (to the extent
required by applicable law or rules). If the Plan is not so approved by the
Corporation's shareholders, the Plan shall terminate and any options granted
hereunder shall be void and have no force or effect.

         3.       Shares Subject to the Plan. Subject to adjustment as provided
in paragraph 13 hereof, an aggregate of 500,000 shares of the Common Stock shall
be available for issuance upon the exercise of all options granted under the
Plan. Such shares may consist either in whole or in part, as the Board in its
discretion shall from time to time determine, either of authorized but unissued
shares of Common Stock or issued shares of Common Stock which have been
reacquired by the Corporation. If any option granted under this Plan expires or
ceases to be exercisable without having been exercised in full, the unpurchased
shares shall thereafter be available for the grant of further options under the
Plan.

         4.       Administration of the Plan. The Plan shall be administered by
the Board. The Board shall, subject to the provisions of the Plan, have the
power to construe the Plan, to determine all questions arising thereunder and to
adopt and amend such rules and regulations for the administration of the Plan as
it may deem desirable.

         5.       Eligibility; Grant of Options.

                  (a)      Options under the Plan shall be granted to each
director of the Corporation who is not otherwise an employee of the Corporation
or any subsidiary of the Corporation (a "Non-Employee Director") on the
Effective Date or, in the case of future Non-Employee Directors, on (i) the date
such director is first duly elected as a director by the shareholders of the
Corporation or the Board, or, if later, (ii) the date such director first
becomes a Non-Employee Director (in either case, the "Initial Grant Date"). In
addition, an option shall be granted to each continuing Non-Employee Director
who is serving as such at the annual meeting of the shareholders, provided that
such individual has been a Non-Employee Director for the preceding six (6)
months (the "Annual Grant Date").

                  (b)      Each Non-Employee Director shall be granted, as of
the Initial Grant Date, with respect to such director, an option to acquire
20,000 shares of Common Stock, subject to adjustment as set forth in paragraph
13 hereof. In addition, in accordance with paragraph (a) above each Non-Employee
Director shall be granted on each Annual Grant Date with respect to such
director an option to acquire 5,000 shares of Common Stock, subject to
adjustment as set forth in paragraph 13 hereof. Each option granted under the
Plan shall be evidenced by an option agreement (an "Agreement") duly executed on
behalf of the Corporation and by the director to


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whom such option is granted, which Agreement shall comply with and be subject to
the terms and conditions of the Plan. An Agreement may contain such other terms,
provisions and conditions not inconsistent with the Plan as may be determined by
the Board. No option shall be deemed to be granted within the meaning of the
Plan and no purported grant of any option shall be deemed effective until such
an Agreement shall have been duly executed on behalf of the Corporation and the
director to whom the option is to be granted.

         6.       Option Price. The option price per share with respect to each
option granted under the Plan shall be 100% of the fair market value on the
applicable Initial Grant Date or applicable Annual Grant Date (in all cases said
date to be referred to as the "Date of Grant"). For purposes of the preceding
sentence, the fair market value of a share of Common Stock shall mean the
closing sale price of the Common Stock on the Date of Grant or, if a public
holiday, weekend or other day in which shares of stock are not publicly traded,
the first trading day immediately prior thereto, or, in case no sale is publicly
reported, the average of the closing bid and asked quotations for the Common
Stock on that date, in any case as reported in the Wall Street Journal or, if
the Common Stock is not then quoted in the Wall Street Journal or an equivalent
publication, as furnished by a member of the National Association of Securities
Dealers, Inc. selected by the Corporation for that purpose.

         7.       Term of Options. The term of each option granted under the
Plan shall be five (5) years from the Date of Grant, subject to earlier
termination as provided in paragraphs 10 and 11 herein.

         8.       Time and Manner of Exercise of Options.

                  (a)      Except as otherwise provided herein, options granted
under the Plan shall not be exercisable for a period of one year from the Date
of Grant. Thereafter, options shall be exercisable in accordance with the terms
of the Plan at any time or from time to time during the term of the option,
subject to the following: (i) not more than one third of the total number of
option shares shall be purchasable on or following the first anniversary of the
Date of Grant; (ii) not more than two thirds of the total number of option
shares shall be purchasable on or following the second anniversary of the Date
of Grant; and (iii) 100% of the option shares shall be purchasable on or
following the third anniversary of the Date of Grant.

                  (b)      Subject to the foregoing, an option granted under the
Plan may be exercised in full at one time or in part from time to time by giving
written notice, signed by the person or persons exercising the option, to the
Corporation, stating the number of shares with respect to which the option is
being exercised. Upon the exercise of the option, the purchase price of the
shares shall be paid in full (i) in cash; (ii) in shares of Common Stock of the
Corporation (not subject to limitations on transfer) valued at the fair market
value of such shares on the trading day immediately preceding the date of
purchase; provided that any shares of Common Stock tendered for payment shall
have been owned for a period of six (6) months or such other period as in the
opinion of the Board shall be sufficient for such shares to be considered
"mature" shares for purposes of accounting for the transaction; or (iii) if the
applicable Agreement so specifies, and subject to such rules as may be
established by the Board through a so-called "cashless exercise" procedure with
a designated broker; or (iv) a combination of the above. The Corporation shall
not be required to deliver certificates for such shares until such payment has
been made.

                  (c)      The holder of an option granted under the Plan shall
not have any rights as a shareholder with respect to the shares subject to the
option until certificates representing such shares are delivered to him by the
Corporation upon the exercise of his option.


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                  9.       Nontransferability of Options. No option granted
under the Plan shall be transferable or assignable by the optionee, otherwise
than by will or the laws of descent and distribution. During the lifetime of the
optionee, the option shall be exercisable only by him. Notwithstanding the
above, the Board, in its sole discretion, may allow for the limited transfer of
an option to family members of the optionee, or a trust benefiting such family
members, for estate planning purposes.

                  10.      Effect of Termination of Services or Loss of Eligible
Director Status. An option granted under the Plan shall terminate within thirty
(30) days immediately following (i) the director's discontinuance of service on
the Board of Directors for any reason, with or without cause, other than the
director's death or the discontinuance of his services due to the circumstances
set forth in paragraph 12 herein, or (ii) the director's loss of Non-Employee
status with respect to the Corporation or any subsidiary of the Corporation. In
either of such events, the optionee may exercise his option during such
thirty-day period, to the extent of the number of shares of Common Stock covered
by his option which were purchasable by him at the date of such termination or
loss of Non-Employee status, as the case may be.

                  11.      Death of Option Holder. In the event of the death of
an optionee while serving as a Non-Employee Director of the Corporation, the
option shall terminate on the earlier of six months following the date of death
or the expiration date of the option as provided by paragraph 7 of the Plan.
Such option may be exercised during such time by the executors or administrators
of the optionee or by any person or persons to whom the option is transferred by
will or the applicable laws of descent and distribution, to the extent of the
full number of shares that the optionee was entitled to purchase under the
option on the date of his death.

                  12.      Change in Control. If an optionee's service as a
member of the Board of Directors is terminated or discontinued due to or as
result of change in control, his option shall become immediately exercisable in
full as of a period beginning thirty (30) days prior to such proceeding, without
regard to the provisions of paragraph 8(a) of the Plan. For purposes of this
paragraph, a "change in control" of the business and operations of the
Corporation shall mean a change in control of a nature that would be required to
be reported in response to Item 5(f) of Schedule 14A of Regulation 14A
promulgated under the Exchange Act, as in effect on the Effective Date; provided
that, without limitation, such a change in control shall be deemed to have
occurred if any "person" (as such term is used in Section 13(d)(2) of the
Exchange Act) after the Effective Date becomes the beneficial owner, directly or
indirectly, of securities of the Corporation representing 20% or more of the
combined voting power of the Corporation's then outstanding securities.
Notwithstanding the foregoing, this paragraph 12 shall not apply to the
distribution by Healthdyne, Inc. to its shareholders of common stock of the
Corporation and such transaction shall not constitute a "change in control"
hereunder.

                  13.      Antidilution. In the event that the outstanding
shares of the Common Stock of the Corporation are changed into or exchanged for
a different number or kind of shares or other securities of the Corporation or
of another corporation by reason of any reorganization, merger, consolidation,
recapitalization, reclassification, stock split-up, combination of shares or
dividends payable in capital stock, appropriate adjustment shall be made in the
number and kind of shares as to which outstanding options, or portions thereof
then unexercised shall be exercisable, to the end that the proportionate
interest of the optionee shall be maintained as before the occurrence of such
event; such adjustment in outstanding options shall be made without change in
the total price applicable to the unexercised portion of such options and with a
corresponding adjustment in the option price per share. Notwithstanding the
foregoing, the Corporation may adjust the option price of any option hereunder
pursuant to a formula established by the Corporation solely to preserve


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without exceeding the value of such option in the event of the spin-off of any
subsidiary of the Corporation.

                  14.      Securities Matters. The exercise of any option
granted hereunder shall only be effective at such time as counsel to the
Corporation shall have determined that the issuance and delivery of shares of
Common Stock pursuant to such exercise will not violate any state or federal
securities or other laws. The optionee desiring to exercise an option may be
required by the Corporation, as a condition of the effectiveness of any exercise
of an option granted hereunder, to agree in writing that all shares of Common
Stock to be acquired pursuant to such exercise shall be held for investment for
his own account without a view to any further distribution thereof, that the
certificates for such shares shall bear an appropriate legend to that effect and
that such shares will not be transferred or disposed of except in compliance
with applicable federal and state laws. The Corporation may, in its sole
discretion, defer the effectiveness of any exercise of an option granted
hereunder in order to allow the issuance of shares of Common Stock pursuant
thereto to be made pursuant to registration or an exemption from registration or
other methods for compliance available under federal or state securities laws.
The Corporation shall be under no obligation to effect the registration pursuant
to the Securities Act of 1933, as amended, of any shares of Common Stock to be
issued hereunder or to effect similar compliance under any state laws.

                  The Corporation shall inform the optionee in writing of its
decision to defer the effectiveness of the exercise of an option granted
hereunder. During the period that the exercise of the option has been
deferred, the optionee may, by written notice, withdraw such exercise and
obtain the refund of any amount paid with respect thereto.

                  15.      Termination and Amendment of the Plan. Unless sooner
terminated as herein provided, the Plan shall terminate ten (10) years from the
Effective Date. The Board may suspend or terminate the Plan or make such
modification or amendment thereto as it deems advisable; provided, however, that
(a) the Plan may not be amended or modified more than once every six months
unless such amendment is necessary to comply with changes to either the Internal
Revenue Code of 1986, as amended, or the Employee Retirement Income Security Act
of 1974, as amended, and (b) except as provided in paragraph 13, the Board may
not, without the approval of the shareholders of the Corporation, change the
number of shares subject to the Plan or any option granted thereunder, extend
the option period provided for in paragraph 7, or materially increase the
benefits under the Plan. No termination, modification or amendment of the Plan
shall, without the consent of an optionee, adversely affect the rights of such
optionee.

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