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                              EMPLOYMENT AGREEMENT

         This Agreement is made by and between AIRTECH INTERNATIONAL
CORPORATION, a Texas Corporation (the "Corporation") and JOHN POTTER (the
"Executive") effective the 1st day of May, 1977.

         WHEREAS, The Corporation is in the business of manufacturing and
marketing commercial air purification technology ,

         WHEREAS, The Executive has considerable experience in the management of
a successful businesses,

         WHEREAS, The Corporation desires to hire Executive as President of the
Company.

         NOW, THEREFORE, in consideration of the promises and of the mutual
covenants and agreements contained in this Agreement, the parties hereby agree
as follows:

         1.       EMPLOYMENT SCOPE AND AUTHORITY. The Corporation hereby
employs the Executive and Executive accepts employment as President of the
Corporation. The Executive shall report and be responsible to the Chief
Executive Officer and the Corporation's Board of Directors. The management
powers shall be superior to all other officers or employees of the
Corporation, except the Chief Executive Officer. Executive shall become and
remain a Director of the Corporation during the term of this agreement.

         2.       TERM. The initial term of the Agreement shall be for ten (10)
years from the date the Agreement is signed by all of the parties.

         3.       CONTINUED TERM. The Executive Committee of the Board of
Directors, after the initial term of the Agreement has expired, may extend
and renew this Agreement for additional ten (10) year terms.

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         4.       DUTIES. The Executive shall serve as President of the
Corporation and shall have such duties, responsibilities and authority as is
customary to such position and such other duties, responsibilities as may
from time to time be assigned by the Chief Executive Officer and the Board of
Directors of the Corporation.

         5.       TIME, ABILITY AND ATTENTION. The Executive shall devote
substantially all of his working time, ability and attention to the business of
the Corporation. Corporation recognizes that the Executive may have other
business interest to which he may devote a reasonable amount of time, provided
such do not conflict with the conduct of the business affairs of the
Corporation.

         6.       PLACE OF PERFORMANCE. The Executive shall maintain his office
at the principal executive offices of the Corporation, as designated from
time to time by the Chief Executive Officer and President of the Corporation,
subject to required travel on behalf of the Corporation.

         7.       COMPENSATION. The Corporation shall pay the Executive the
salary, reimbursement of expenses and provide the benefits as specified below.

         (a)      SALARY. The Corporation shall pay the Executive a salary at
                  the annual rate of $250,000 commencing May 1, 1997, payable
                  bimonthly or otherwise in accordance with the Corporation's
                  payroll practices for all employees;

         (b)      INCENTIVE BONUS. As a further inducement to accept the
                  position with the Corporation, during the term of this
                  Agreement and extensions thereof, Corporation shall pay to
                  Executive an annual bonus to be determined in good faith by
                  the Board of Directors. The Board of Directors of the
                  Corporation shall, within six (6) months of the date of this
                  Agreement, structure, institute and establish an incentive
                  bonus program specifying how and when bonuses are to paid
                  pursuant to this paragraph.


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         (c)      BENEFITS. Executive shall be entitled to participate in the
                  Corporation's employee benefit programs in effect from time to
                  time for employees at comparable levels of responsibility.
                  Participation will be in accordance with any applicable
                  policies adopted by the Board of Directors. Executive shall be
                  entitled to vacations, absences for illness, and to similar
                  benefits of employment to the extent such benefits are
                  generally offered to employees of the Corporation at a
                  comparable level of responsibility, subject to the policies
                  and procedures adopted by the Board of Directors.

         (d)      EXPENSES. Subject to the policies and procedures as may be
                  adopted by the Corporation's Board of Directors, Executive
                  shall be entitled to reimbursement for travel, entertainment
                  and other expenses actually incurred on behalf of Corporation
                  (upon presentation of reasonable evidence thereof) to the
                  extent such expenses are incurred in connection with direct
                  activities of the Corporation, and to the extent similar
                  reimbursements are generally available to employees of the
                  Corporation at a comparable level of responsibility.

         (e)      SERVICES. The Corporation shall furnish Executive office
                  space, personnel and such other facilities and services as
                  reasonably required for Executive to perform the duties of
                  President of the Corporation.

         8.       TERMINATION BY CORPORATION. This Agreement, and the employment
of Executive, hereunder, shall terminate immediately upon the occurrence of any
one of the following events:

         (a)      DEATH.  Upon the death of Executive.


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         (b)      DISABILITY. The Executive becomes incapacitated due to
                  physical or mental illness and Executive shall have been
                  absent from employment on a full-time basis for one hundred
                  fifty (150) consecutive days, and fails to return to perform
                  the duties assigned by the Corporation on a full-time basis
                  within thirty (30) days after delivery of written notice of
                  termination of the Agreement.

         (c)      AGREEMENT. The mutual written agreement of the Corporation and
                  the Executive.

         (d)      TERM. The expiration of the term, as extended, of this
                  Agreement.

         (e)      FOR CAUSE. (i) wilful, intentional and continued failure to
                  perform the duties of President of the Corporation, except
                  disability, for more than thirty (30) days after delivery of
                  written demand by the Corporation for performance which shall
                  specify the manner and means which the Corporation believes
                  that the Executive is not performing the duties of President,
                  (ii) the conviction of the Executive of a criminal act of
                  moral turpitude, have or liable to have an adverse affect on
                  the Corporation, its business, reputation or good will. For
                  purposes of this paragraph, no act, or failure to act, on the
                  Executive's part shall be considered "wilful" or "intentional"
                  unless done, omitted to be done, knowingly, in bad faith, and
                  without reasonable belief that such action or omission was in
                  the best interest of the Corporation. The Executive shall not
                  be terminated for cause by the Corporation without first
                  having received the opportunity, together with legal counsel,
                  to be heard before the Board of Directors and delivery of
                  written notice specifying the provisions of this Agreement and
                  the facts and circumstances relied upon as basis for
                  termination and


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                  a written finding of facts and good faith opinion of the Board
                  of Directors that the Executive violated clause (i) and/or
                  (ii) of this paragraph.

         9.       TERMINATION BY EXECUTIVE. This Agreement may be terminated by
the Executive upon the occurrence of any one of the following events:

         (a)      DISABILITY. In the event the Executive's health impairs the
                  performance of the duties of President and such is hazardous
                  to Executive's physical or mental health or life, provided a
                  written statement from a qualified physician is delivered to
                  the Board of Directors reasonably describing such impairment.

         (b)      GOOD CAUSE. (i) the Corporation or the Board of Directors
                  terminates this Agreement pursuant to paragraph 3, (ii) the
                  Board of Directors fails to reelect Executive as President and
                  Director of the Company or removes Executive from such
                  position or positions, (iii) the Board of Directors shall fail
                  to vest the powers and authority of President, (iv) the Board
                  of Directors shall fail to comply with any material provision
                  of the Agreement which is not cured within ten (10) days of
                  delivery of written notice to the Board of Directors; or (v)
                  any purported termination by Corporation not in compliance
                  with the requirements of paragraph 8(e).

         10.      EXECUTIVE COMPENSATION UPON TERMINATION. The Corporation shall
pay the Executive upon the event of termination the compensation set forth
below:

         (a)      DEATH. The Corporation shall continue the salary for a period
                  of twelve (12) months from and including the month of death
                  and pay such in accordance with the payroll policies of the
                  Corporation to the representative of the deceased Executive's
                  estate.


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         (b)      DISABILITY. The Corporation shall continue the salary for a
                  period of six (6) months after this agreement is terminated
                  pursuant to paragraph 8 (b), provided the salary payments may
                  be reduced by the amount of payment received by the Executive
                  under disability benefits plans of the Company, if any.

         (c)      BREACH OF AGREEMENT. In the event this Agreement is terminated
                  pursuant to paragraph 9(b) the Corporation shall pay Executive
                  (i) full salary through Date of Termination at the annual rate
                  then in effect at the time Notice of Termination is delivered,
                  (ii) in lieu of further salary payments after the Date of
                  Termination, the Corporation shall pay as severance pay to
                  Executive, the greater of one million dollars ($1,000,000) or
                  an amount equal to two times the salary remaining unpaid under
                  the term of this agreement or two times the amount equal to
                  the annual salary in effect at the Date of Termination,
                  payable in one lump sum on or before five (5) business days
                  after the Date of Termination; and (iii) if the termination
                  arises out of a breach by the Company of this agreement, the
                  Corporation shall pay all other damages to which the Executive
                  may be entitled in law or equity resulting from such breach,
                  including damages for loss of benefits, legal expenses
                  incurred and costs of court. In the event this Agreement is
                  terminated pursuant to paragraph 8(e) the Corporation shall be
                  obligated to pay Executive any salary due to the Date of
                  Termination.

         (d)      OPTIONAL SEVERANCE PAYMENT. Executive upon the event of the
                  Corporation's obligation to pay severence, may in Executive's
                  sole discretion and option elect to accept a number of shares
                  of registered stock of the Corporation determined by


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                  dividing the severance amount due by $1.00 which number of
                  shares when delivered shall be in full payment and
                  satisfaction of the Corporation's obligation to Executive.

         (e)      CONTINUATION OF BENEFITS. Except for termination for Cause,
                  the Corporation shall maintain in full force and effect, for
                  the benefit of the Executive for twelve (12) months, all
                  employee benefits, plans and programs in which Executive was
                  entitled to participate and did participate immediately prior
                  to the Date of Termination. If the Executive is terminated for
                  Cause, the Corporation shall terminate all employee benefits,
                  plans and programs in which Executive was entitled to
                  participate and did participate immediately prior to the Date
                  of Termination.

         (f)      MITIGATION. The Executive shall not be required to mitigate
                  the amount of any payment provided under this paragraph 10 by
                  seeking other employment or otherwise.

         11.      NON-COMPETITION. Executive expressly agrees that while this
agreement is in effect, and except for termination for Good Cause, for a period
of two (2) years following the termination of this Agreement, Executive will not
directly or indirectly, as an employee, agent, proprietor, partner, broker,
stockholder, officer, director, or otherwise, render any services to, on
Executives' own behalf or on behalf of any other person or entity, engage in as
an employee or owner of any competitive business or organization located within
a 100 mile radius of the Counties of Dallas, Tarrant, Denton, Collin, Rockwall,
Texas or any other county in any state in which the Corporation then maintains
an office that would compete directly or indirectly with Corporation's business,
without prior written consent of Corporation. The term "competitive business"
shall include but shall not be limited to any business that manufactures and
markets commercial air purification


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technology. Executive further expressly agrees that Executive will not use
for Executives' own benefit or disclose to any person any information,
including confidential information, which is obtained or learned while acting
as Executive, without prior written consent of the Corporation. The
agreements contained in this paragraph on the part of Executive shall be
construed as an integral part of an enforceable agreement and the agreements
contained herein were made at the time this agreement was consummated by the
parties. The Executive acknowledges and agrees that the non-competition
restrictions contained herein are fair and reasonable as to geographical
area, length of time and scope of activity restrained. The existence of any
claim or cause of action against Executive by the Corporation, whether
predicated on this Agreement or otherwise, shall not constitute a defense to
the enforcement by the Corporation of the agreements contained in this
paragraph.

         12.      ADMINISTRATIVE PROVISIONS. The terms of this Agreement shall
be administered pursuant to the following provisions:

         (a)      DEFINITION. "Date of Termination" shall mean (i) the date of
                  death of Executive, (ii) thirty (30) days after notice of
                  termination is given for disability, (iii) the date specified
                  in the notice of termination for cause or good cause;
                  provided, if within thirty (30) days after delivery of a
                  notice of termination the person receiving such notice
                  notifies the other in writing that a dispute exists, the
                  Date of Termination shall be the date he dispute is finally
                  determined by mutual agreement or otherwise.

         (b)      PARTIES BOUND. This Agreement shall be binding on and inure
                  to the benefit of the parties and their respective heirs,
                  executors, administrators, legal representatives, successors
                  and assigns.


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         (c)      ASSIGNMENT. Executive shall have no right to transfer or
                  assign any interest in this Agreement without the prior
                  written consent of the Corporation.

         (d)      TIME LIMITS. Time is of the essence in this Agreement; and all
                  time limits shall be strictly construed and rigidly enforced.

         (e)      NO WAIVER. A failure or delay in the enforcement of the rights
                  detailed in this Agreement by Corporation shall not constitute
                  a waiver of those rights or be considered a basis for
                  estoppel. Corporation may exercise its rights under this
                  Agreement despite any delay or failure to enforce those
                  rights.

         (f)      DISPUTE OR CONTEST. In the unlikely event that a dispute
                  occurs or an action in law or equity arises out of the
                  operation, construction, or interpretation of this Agreement,
                  the prevailing party shall be entitled, in addition to any
                  other relief granted to reasonable expenses for attorneys'
                  fees and costs incurred by such party in the action,.

         (g)      PARAGRAPH HEADINGS. The paragraph headings used in this
                  Agreement are descriptive only and shall have no legal force
                  or effect whatever.

         (h)      TEXAS LAW. This Agreement shall be subject to and governed by
                  the laws of the State of Texas. Any and all obligations or
                  payments are due and payable in Dallas County, Texas.

         (i)      SEVERABILITY. If any provision of this Agreement shall, for
                  any reason, be held violative of any applicable law, and so
                  much of the Agreement is held to be unenforceable, then the
                  invalidity of such a specific provision of this Agreement
                  shall not be deemed to invalidate any other provisions of this
                  Agreement, which other


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                  provisions shall remain in full force and effect unless
                  removal of the invalid provisions destroy the legitimate
                  purposes of this Agreement, in which event this Agreement
                  shall be cancelled.

         (j)      MODIFICATION OF AGREEMENT. This Agreement represents the
                  entire Agreement by and between the parties, except as
                  otherwise provided in this Agreement, and it may not be
                  changed except by written amendment duly executed by all
                  parties.

         (k)      NOTICES. All notices and communications pursuant to this
                  Agreement shall be in writing and delivered when sent by
                  United States certified mail, return receipt requested,
                  postage prepaid, addressed as follows:

                  If to Executive:    John Potter
                                      4528 New Orleans Dr.
                                      Plano, TX 75093

                  If to Corporation:  Airtech International Corporation
                                      15400 Knoll Trail Suite 106
                                      Dallas, Texas 75248

or such other address an any party may have furnished to the other in writing
upon receipt by such party.


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SIGNED, accepted and agreed to the first date stated above, by the undersigned
parties.

CORPORATION:

AIRTECH INTERNATIONAL CORPORATION


   /s/ C J Comu
-------------------------------------------------------
C. J. Comu, Chief Executive Officer

EXECUTIVE:


   /s/ John Potter
-------------------------------------------------------
John Potter


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