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     10.24  Lease Agreement, dated April 25, 1995 between Five-Forty North
            Associates a Partnership and the Registrant, for Registrant's
            offices, demonstration facility, and equipment manufacturing
            facilities.


                                 LEASE AGREEMENT

                           FIVE-FORTY NORTH ASSOCIATES
                                   (Landlord)


                                KYZEN CORPORATION
                                    (Tenant)

                           First Floor, South End and
                              Second Floor, Center
                           540 North Commercial Street
                            Manchester, New Hampshire


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                                    CONTENTS


ARTICLE I - Leased Premises; Construction; Possession
ARTICLE II - Term of Lease
ARTICLE III - Option to Renew 
ARTICLE IV - Rent 
ARTICLE V - Security Deposit
ARTICLE VI - Quiet Enjoyment 
ARTICLE VII - Common Areas of the Building; Maintenance Thereof 
ARTICLE VIII - Condition of Leased Premises; Repairs 
ARTICLE IX - Improvements by Tenant 
ARTICLE X - Machinery and Equipment - Trace Fixtures
ARTICLE XI - Utilities
ARTICLE XII - Use of Leased Premises
ARTICLE XIII - Hazardous Waste or Substances 
ARTICLE XIV - Assignment; Subleasing
ARTICLE XV - Taxes and Assessments 
ARTICLE XVI - Mechanic's Lien 
ARTICLE XVII - Eminent Domain 
ARTICLE XVIII - Liability 
ARTICLE XIX - Rules and Regulations
ARTICLE XX - Landlord's Insurance 
ARTICLE XXI - Tenant's Insurance 
ARTICLE XXII - Destruction or Damage 
ARTICLE XXIII - Repossession by Landlord 
ARTICLE XXIV - Mortgage Lien 
ARTICLE XXV - Default 
ARTICLE XXVI - Access to Leased Premises
ARTICLE XXVII - Notices 
ARTICLE XXVIII - Signs; Exterior Appearance; Pylon; Sign
ARTICLE XXIX - Short Form Recording 
ARTICLE XXX - No Broker 
ARTICLE XXXI - Warranties and Representations of Tenant 
ARTICLE XXXII - Succession 
ARTICLE XXXIII - Waiver 
ARTICLE XXXIV - Governing Law
ARTICLE XXXV - Counterparts
ARTICLE XXXVI - Modification; Entire Agreement 
ARTICLE XXXVII - Section Headings
ARTICLE XXXVIII- Severability


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         LEASE dated this 25th day of April, 1995, by and between FIVE-FORTY
NORTH ASSOCIATES, a New Hampshire limited partnership ("Landlord") and KYZEN
CORPORATION, a Utah corporation ("Tenant").

                                   WITNESSETH:

ARTICLE I - LEASED PREMISES; CONSTRUCTION; POSSESSION

         1.1 Landlord hereby leases to Tenant and Tenant hereby leases from
Landlord, upon and subject to the terms and provisions of this Lease, an area of
approximately Eleven Thousand Three Hundred Twenty-Nine (11,329) square feet, as
cross-hatched on the floor plan attached hereto as Exhibit A-1 (the "Leased
Premises"), which area is a part of a warehouse located at 540 Commercial
Street, Manchester, Hillsborough County, New Hampshire, as more particularly
described in Exhibit A-2 attached hereto (the "Building").

         1.2 Landlord shall perform the "Landlord's Work" substantially in
accordance with the Landlord's and Tenant's Architectural and Construction Work
described in Exhibit B attached hereto by approximately June 1, 1995 subject to
delays caused by governmental restrictions, strikes, lock-outs, shortages of
labor or material, acts of God, war or civil commotion, fire, unavoidable
casualty, inclement weather or cause beyond the reasonable control of Landlord.

         1.3 For all purposes in this Lease, the term "Tenant's Proportionate
Share" shall mean six and four tenths percent (6.4%), which is the ratio that
the gross square feet of the Leased Premises bears to the total rentable square
feet of the Building.

ARTICLE II - TERM OF LEASE

         2.1 The original term of this Lease is for a period of three (3) years,
which period will commence on June 1, 1995 and will end on May 31, 1998.

         2.2 The term "Lease Year", as used herein, shall mean the period which
commences on June 1 of each year and terminates on May 31 of each year.

         2.3 If Tenant holds over after the expiration of this term or any
exercised option term without objection from Landlord, then such holding over
will not extend the term of this Lease, but will create a month-to-month tenancy
under the same conditions as this Lease except that rent shall be paid in the
amount of one hundred twenty-five percent (125%) the base rent set forth in
Section 4.1 hereof.

ARTICLE III - OPTION TO RENEW

         3.1 Tenant shall have the option to renew this Lease for one (1)
additional terms of one (1) year. So long as Tenant is not in default under the
terms of this Lease, said option may be exercised by giving notice to Landlord
at least ninety (90) days prior to the expiration of the original term of the
Lease of Tenant's intent to exercise the option. The rent payable by Tenant
during the renewal term shall be as specified in Section 4.ltd) below.

ARTICLE IV - RENT

         4.1 Tenant shall pay Landlord (at the address specified in Article
XXVIII hereof), as base rent for the Leased Premises during the term of this
Lease (the "Base Rent"), as follows:

         (a) During Lease Year 1, the annual sum of Fifty-Six Thousand Seven
Hundred Dollars ($56,700), payable in equal monthly installments of Four
Thousand Seven Hundred Twenty-Five Dollars ($4,725);

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         (b) During Lease Year 2, the annual sum of Sixty-One Thousand Five
Hundred Dollars ($61,500), payable in equal monthly installments of Five
Thousand One Hundred Twenty-Five Dollars ($5,125);

         (c) During Lease Year 3, the annual sum of Sixty-Six Thousand Nine
Hundred Dollars ($66,900), payable in equal monthly installments of Five
Thousand Five Hundred Seventy-Five Dollars ($5,575; and

         (d) During Lease Year 4 (in the event that Tenant exercises its option
to renew), the annual sum of Seventy-Three Thousand Five Hundred Sixty Dollars
($73,560), payable in equal monthly installments of Six Thousand One Hundred
Thirty Dollars ($6,130).

         4.2 All rent is payable in advance, without demand, in fixed monthly
installments of one-twelfth (1/12) of the then-current yearly Base Rate on or
before the first day of each and every month during the term hereof. If this
lease begins on any day other than the first (1st) of any calendar month, then
the rent for the first month will be prorated for the number of days in that
month that this lease is effective. A similar proration will be made for the end
of the term.

         4.3 The Base Rent and all other sums payable by Tenant hereunder shall
be referred to as "Rent". For further sums payable by Tenant as Rent (sometimes
called "Additional Rent") see Articles VII, VIII, XI, XV and XX.

         4.4 It is understood that the Base Rent, Monthly Estimated Common Area
Maintenance Charge (hereinafter defined) and Tenant Proportionate Share of Real
Estate Taxes (hereinafter defined) is payable on or before the first day of each
month without offset or deduction of any nature. In the event such Rent is not
received when due or any check tendered to Landlord is returned to Landlord as
uncollectible, Tenant shall pay the applicable service charges set forth in this
Section 4.4, which Landlord and Tenant agree are a fair and reasonable estimate
of the costs to be incurred by Landlord by reason of such late payment. The
service charge for a late payment shall be an amount equal to five percent (5%)
of any installment of rent and other charges past due for more than five (5)
days; provided, however, interest on such past due installment and late payment
charge shall accrue at the rate of eighteen percent (18%) per annum after the
thirtieth (30th) day such installment is past due until paid. The service charge
for a returned check shall be Thirty-Five Dollars ($35). In no event shall the
aggregate of the interest to be paid by Tenant, plus any other amounts paid in
connection with the transaction evidenced hereby which would under applicable
law be deemed "interest", ever exceed the maximum amount of interest which,
under applicable law, could be lawfully charged to Tenant hereunder (the
"Maximum Rate"). Therefore, none of the terms of this Lease shall ever be
construed to create a contract to pay interest at a rate in excess of the
Maximum Rate, and Tenant shall not be liable for interest in excess of that
determined at the Maximum Rate, and the provisions of this Section shall control
all other provisions of this Lease. If any amount of interest taken or received
by Landlord shall be in excess of the maximum amount of interest which, under
applicable law, could lawfully have been collected under this Lease, then the
excess shall be deemed to have been the result of a mathematical error by
Landlord and Tenant and shall be refunded promptly to Tenant.

         4.5 Any payment by Tenant or acceptance by Landlord of an amount less
than that due under the terms hereof will be treated as a payment on account,
regardless of any endorsement appearing on any such check or any statement made
by Tenant to the contrary.

ARTICLE V - SECURITY DEPOSIT

         5.1 Upon the execution hereof, and prior to the commencement of the
lease term under Article II hereof, Tenant shall pay to and deposit with
Landlord the sum of Four Thousand Seven Hundred Twenty-Five Dollars ($4,725), as
security for the full and faithful performance by Tenant of all the terms of
this Lease required to be performed by Tenant. Landlord may use, apply, or
retain the whole or any part of the money deposited as security hereunder to the
extent required for the payment of any rent and additional rent or other sum(s)
as to which Tenant is in default or for any sum(s) which Landlord may expend or
may be required to expend by reason of Tenant's default in respect of any of the
conditions of this Lease, including, but not limited to, any damages or
deficiency in reletting of the Leased Premises whether such damages or
deficiency accrued before or after summary

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proceedings or other reentry by Landlord. In the event of Landlord's sale or
lease of the Leased Premises of which the Leased Premises forms apart, Landlord
shall have the right to transfer said security deposit to the purchaser or
lessee, and Landlord shall thereupon be released from all liability for the
return of such security deposit. In the event of such a transfer, Tenant shall
look solely to said transferee for the return of said security deposit. Tenant
shall not assign or encumber the money deposited as security without the prior
written consent of Landlord, and Tenant agrees that neither Landlord nor its
successors and assigns shall be bound by any such assignment or encumbrance.
Tenant agrees that the money deposited as security hereunder will not be used to
pay the Rent for the last month of the term hereof without the prior written
consent of Landlord. Tenant shall not be entitled to any interest on the money
deposited as security hereunder. Subject to the terms of this Section, in the
event that Tenant shall comply with all of the terms of this Lease, the money
deposited as security hereunder will be returned to Tenant at the expiration of
the term hereof and after delivery of possession of the Leased Premises to
Landlord.

ARTICLE VI - QUIET ENJOYMENT

         6.1 Landlord shall put Tenant into possession of the Leased Premises
on the Commencement Date, and Tenant, upon paying the rent and observing the
other covenants and conditions herein, upon its part to be observed, shall have
peaceable and quiet and enjoyment of the Leased Premises.

ARTICLE VII - COMMON AREAS OF THE BUILDING; MAINTENANCE THEREOF

         7.1 The term "Common Area" is defined for all purposes of this Lease
as that part of the Building intended for the common use of all tenants,
including among other facilities (as such may be applicable to the Building)
parking areas, private streets and alleys, landscaping, curbs, loading areas,
sidewalks, lobbies, hallways, lighting facilities, drinking fountains, public
toilets, and the like but excluding space in buildings (now or hereafter
existing) designed for rental for commercial purposes, as the same may exist
from time to time, and further excluding streets and alleys maintained by a
public authority. Landlord reserves the right to change from time to time the
dimensions and location of the Common Area. Tenant, its employees and customers,
and, when duly authorized pursuant to the provisions of this Lease, its
subtenants shall have the nonexclusive right to use the Common Area as
constituted from time to time. Such use shall be in common with Landlord, other
tenants in the Building and other persons permitted by Landlord to use the same,
and shall be subject to such reasonable rules and regulations governing use as
Landlord may from time to time prescribe, including the designation of specific
areas within the Building or in reasonable proximity thereto, in which
automobiles owned by Tenant, its employees, subtenants, licensees and
concessionaires shall be parked. The Tenant shall be provided twenty (20)
parking spaces; ten (10) of which shall be on site [three (3) in front of the
Building and seven (7) on the river side of the Building 1 and ten (10) of which
shall be in the Arms Parking Lot. Tenant shall not take any action which would
interfere with the rights of other persons to use the Common Area. Landlord may
temporarily close any part of the Common Area for such periods of times as may
be necessary to make repairs or alterations or to prevent the public from
obtaining prescriptive rights. Landlord shall be responsible for the operation,
management, and maintenance of the Common Area, the manner of maintenance and
the expenditures therefor to be in the sole discretion of Landlord.

         7.2 - (a) In addition to Monthly Rent and any other charges prescribed
in this Lease, beginning in Lease Year 2, Tenant shall pay to Landlord Tenant's
Proportionate Share of any increase from the cost incurred in the calendar year
1995, for the cost of ownership, operation and maintenance of the Common Area
(including, among other costs, those for lighting, painting, cleaning,
inspecting, repairing, replacing, and removing of snow and ice from the Common
Area, and the cost of heating, cooling and other utilities for any lobbies and
hallways, and, in the event that the Leased Premises and other areas of the
Building which are leased are not separately metered for utilities, the costs of
electricity, heating, cooling and other utilities servicing the Building) which
may be incurred by Landlord in its discretion, including the cost of maintaining
and repairing all utility mains, lines, conduits and other facilities located
on, above or under the Common Area, a reasonable allowance for Landlord's
overhead costs and for depreciation of maintenance equipment (collectively, the
"Common Area Maintenance Charges"). Tenant's Proportionate Share of the Common
Area Maintenance Charges for Lease Year 1 is calculated to be $12,348 per year,
which amount is included in the Base Rent stated in Article IV.

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         (b) During Lease Year 2, Tenant will pay Landlord a "Monthly Estimated
Common Area Maintenance Charge" in an amount to be determined by Landlord,
monthly in advance, payable at the same time and place as the Monthly Rent is
payable. Landlord shall have the right to adjust such monthly estimate on an
annual basis, pursuant to the following paragraph.

         (c) Beginning in 1996, within ninety (90) days of the end of each
calendar year occurring during the Term of this Lease (or subsequent to the
expiration or other termination of this Lease, if such occurs on a date other
than the last day of a calendar year), Landlord will give Tenant notice of the
total amount paid by Tenant for the relevant calendar year together with the
actual amount of Tenant's Proportionate Share of the Common Area Maintenance
Charges (the "Total Cost") for such calendar year. If the actual amount of
Tenant's Proportionate Share of the Total Cost with respect to such period
exceeds the aggregate amount previously paid by Tenant with respect thereto
during such period, Tenant shall pay to Landlord the deficiency within fifteen
(15) days following notice from Landlord; however, if the aggregate amount
previously paid by Tenant with respect thereto exceeds Tenant's Proportionate
Share of the Total Cost for such period, then, at Landlord's election, such
surplus (net of any amount then owing by Tenant to Landlord) shall be credited
against the next ensuing installment of any such cost due hereunder by Tenant or
against any other amount of Rent owing by Tenant to Landlord hereunder, or
Landlord may refund such net surplus to Tenant. Periodically, during the Term of
this Lease, Landlord shall have the right to estimate Tenant's Proportionate
Share of Common Area Maintenance Charges for the next fiscal period (determined
by Landlord) of the Term of this Lease, whereupon, Tenant shall pay Landlord
such amounts as may be so indicated by Landlord in the same manner as the
Monthly Estimated Common Area Maintenance Charge.

         7.3 Tenant shall furnish to Landlord upon request a complete list of
license numbers of all automobiles operated by Tenant, its employees,
subtenants, licensees or concessionaires. Tenant agrees that if any automobile
or other vehicle owned by Tenant or any of its employees, subtenants, licensees
or concessionaires, or any of their respective employees, shall at any time be
parked in any part of the Building, other than the specific areas designated by
Landlord from time to time for employee parking, Landlord shall be and is hereby
authorized to cause such automobile or other vehicle to be removed to such other
location, either within or beyond the Building. Tenant agrees to indemnify
Landlord, its employees, and agents and holds each of them harmless from any and
all claims of whatsoever nature which may arise by reason of such removal of
vehicles owned by Tenant or any of its employees, subtenants, licensees or
concessionaires.

ARTICLE VIII - CONDITION OF LEASED PREMISES; REPAIRS

         8.1 Subject to the terms of Article I of this Lease, Tenant accepts the
Building, improvements, and any equipment or fixtures on or in the Leased
Premises "as is" and in their existing condition and agrees that no
representation, statement or warranty, express or implied, has been made by or
on behalf of Landlord as to such condition, or as to the use that may be made of
such property.

         8.2 If the Leased Premises is now, or at any time during the term of
this Lease becomes, a "Public Accommodation" under the Americans with
Disabilities Act of 1990 (the "ADA"), Tenant shall, at its sole expense, be
responsible for (i) compliance with Title ILI of the ADA to the extent that the
AD.A imposes obligations on the procedure and design of any alterations to the
Leased Premises made by Tenant, and (ii) making modifications in its policies,
practices and procedures in connection with the operating of Tenant's business.
If a failure to make such modifications constitutes a violation of the ADA,
Tenant shall indemnify and hold harmless Landlord with respect to its failure to
comply with the foregoing responsibilities. Any work to be performed Tenant
pursuant to this Section 8.2 shall be governed by all the provisions set forth
in Section 9.1 below. Tenant shall have no responsibility for, nor shall it be a
part of the Common Area Maintenance, any work required by the ADA to other
tenant space in the Building or in the common areas of the Building unless such
work is required by Tenant's use of the Leased Premises.

         8.3 Landlord shall maintain in good repair the structural integrity of
the roof, and exterior walls of the Leased Premises, and the structural beams,
structural columns and other structural parts of the Leased Premises, and the
cost of such amount shall be reimbursed to Landlord as part of the Common Area
Maintenance Charges. Tenant shall keep, during the term hereof, at its own cost
and expense, both the interior of the Leased 

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Premises, excluding the structural integrity of the roof and exterior walls, in
as good condition as the same was at the commencement of the term hereof,
reasonable wear and tear, taking by eminent domain and damage due to fire or
casualty insured against excepted. Tenant shall replace, at its own cost and
expense, window glass, if any, of the same kind and quality, reasonable wear and
tear, taking by eminent domain and damage due to fire or other casualty insured
against excepted. Tenant shall replace and/or repair, at its own cost and
expense, all light bulbs and lighting fixtures which are damaged, broken or
cease to function during the term hereof, with bulbs or fixtures of the same
kind and quality. Tenant shall be responsible for regular service and routine
maintenance of the heating/ventilating/air conditioning system servicing the
Leased Premises.

         8.4 Tenant shall rake good we of the Leased Premises and keep the same
free from waste at all times. Tenant shall keep the Leased Premises and
sidewalks, service-ways and loading areas adjacent to the Leased Premises neat,
clean and free from dirt or rubbish at all times, and shall store all trash and
garbage within the Leased Premises, arranging for the regular pick-up of such
trash and garbage at Tenant's expense. Removal of garbage and trash shall be
made only in the manner and areas prescribed by Landlord. Tenant shall arrange
for the regular pick up of trash and refuse at Tenant's expense, unless Landlord
provides other refuse service, in which case Tenant shall use such other refuse
service and pay the cost of such service as specified by Landlord. Tenant shall
not operate an incinerator or burn trash or garbage within the Building. Tenant
shall procure at its sole expense all permits and licenses required for the
transaction of business in the Leased Premises and otherwise comply with all
applicable laws, ordinances, and governmental regulations affecting the
Building, including those relating to Hazardous Waste or Substance (hereinafter
defined) now in force or that may be hereafter enacted or promulgated.

 ARTICLE IX - IMPROVEMENTS BY TENANT

         9.1 Tenant shall not make or allow to be made an alterations,
installations, additions or improvement in or to the Leased Premises, or place
heavy furniture or equipment within the Leased Premises, without Landlord prior
written consent, which consent shall not be unreasonably withheld or delayed.
Any such alterations, additions or improvements to the Leased Premises shall be
governed by the following terms:

         (a) No such alteration, addition or improvement shall lessen the fair
         market value of the Leased Premises or the Building and all such
         improvements are performed in class and quality at least equal to the
         original construction work; 
         (b) All work for any such alteration, addition or improvement shall be 
         performed by a contractor approved by Landlord prior to the 
         commencement of the work, and Landlord shall approve the construction 
         contract which shall be between the Tenant and the approved contractor;
         (c) Prior to the commencement of work on any such alteration, addition
         or improvement, Tenant shall procure, at its own cost and expense, all
         necessary permits; furthermore, the plans and specifications covering
         the same will have been submitted to and approved by (I) Landlord,
         (ii) all municipal or other governmental departments or agencies
         having jurisdiction over the subject matter thereof, and (iii) any
         mortgagee having an interest in or lien upon the Leased Premises or
         the Building if required by the terms of the mortgage, it being
         understood that Landlord will not unreasonably refuse to join in any
         application to any such mortgagee or governmental agency to obtain
         such approval with respect to any reasonable alteration, addition or
         improvement; 
         (d) In carrying out all such alterations, additions and improvements,
         Tenant shall comply with the standards, guidelines and specifications
         imposed by all municipal or other governmental departments and
         agencies having jurisdiction over the same, including without
         limitation, all building codes;
         (e) Prior to the commencement of work on any such alteration, addition
         or improvements, Tenant shall have procured and delivered to Landlord
         the policy of Builder's Risk insurance hereinafter referred to in
         Section 21.2 hereof or additional fire and extended coverage insurance
         as required by Section 21.3 hereof, whichever is applicable;
         (f) All work shall be completed promptly and in a good and workman
         like manner and shall be performed in such a manner that no mechanics,
         materialmens or other similar liens shall attach to Tenant's leasehold
         estate, and in no event shall Tenant permit, or be authorized to
         permit, any such liens or other claims to be asserted against Landlord
         or Landlord's rights, estate and interest with respect to the



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         Leased Premises or the Building; and at the completion of all work
         Tenant shall obtain waivers of mechanics and materialmens liens from
         all persons performing work on or on furnished material to the Leased
         Premises; and 

         (g) Any such alteration, addition or improvement made by Tenant
         pursuant to the terms hereof shall, at the expiration of the term
         hereof become and remain the property of Landlord, provided, however,
         that Landlord may, at its option and upon notice to Tenant not less
         than ninety (90) days prior to such expiration, require Tenant to
         remove any such alterations, additions, and improvements and to
         restore the Leased Premises to their condition as at the beginning of
         the term hereof, reasonable wear and tear, taking by eminent domain
         and damage due to fire or other casualty insured against excepted.

ARTICLE X - MACHINERY AND EQUIPMENT - TRADE FIXTURES

         10.1 All alterations, installations, additions or improvements, other
than moveable furniture and moveable trade fixtures, made by Tenant to the
Leased Premises shall remain upon and be surrendered with the Leased Premises
and become the property of Landlord at the expiration or termination of this
Lease or the termination of Tenant's right to possession of the Leased Premises;
provided, however, that Landlord may require Tenant, at Tenants cost, to remove
any and all of such items that are not building standard within ten (10) days
following the expiration or termination of this Lease, or the termination of
Tenant's right to possession of the Leased Premises. Tenant, at it's sole cost
and within ten (10) days following the expiration or termination of this Lease,
shall remove all of Tenant's property from the Leased Premises. Any such
property which may be removed pursuant to the preceding sentence and which is
not so removed prior to the expiration or earlier termination of this Lease may
be removed from the Leased Premises by Landlord and stored for the account of
Tenant; and if Tenant fails to reclaim such property within thirty (30) days
following such expiration or earlier termination of this Lease, then such
property will be deemed to have been abandoned by Tenant, and may be
appropriated, sold, destroyed or otherwise disposed of by Landlord without
notice to Tenant and without obligation to account therefor. Tenant shall pay to
Landlord the cost incurred by Landlord in moving, storing, selling, destroying
or otherwise disposing of any such property.

ARTICLE XI - UTILITIES

         11.1 The electricity servicing the Leased Premises is not currently 
separately metered. At Landlord's option, Tenant shall:

         (a) Reimburse Landlord for electricity usage pursuant to an agreement
based upon Tenant's power usage at its former facility; or

         (b) Landlord will submeter Tenant's electric usage, in which event
Tenant will reimburse Landlord based on its actual usage; or

         (c) Landlord will install a separately metered electric service to the
Leased Premises, and Tenant shall pay for its usage directly to Public Service
Company of New Hampshire.

         11.2 Subject to the provisions of 11.1 above, if the following
utilities are separately provided to the Leased Premises, Tenant shall make
arrangements for and pay when due all charges for gas, oil, electricity, water,
light, heat, air conditioning, sewer, power, telephone and any other services
used on or about or supplied to the Leased Premises and shall indemnify Landlord
against any liability on such account. Landlord shall not be liable for any
failure of water supply or electric current or of any service by any utility; or
injury to persons (including death) or damage to property resulting from steam,
gas, electricity, water, rain or snow which may flow or leak from any part of
the Leased Premises or from any pipes, appliances or plumbing works, on the
street or subsurface, or from any other place; or for interference with light or
other easements, however caused.

         11.3 Tenant shall, at its sole cost and expense, maintain, repair,
change and improve the water, sewer, electric and other utility systems which
are located within the Leased Premises. Any work performed by Tenant under this
Section 11.2 shall be governed by all of the terms contained in Section 9.1 of
this Lease.


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 ARTICLE XII - USE OF LEASED PREMISES

         12.1 Without the prior written consent of Landlord, Tenant may use the
Leased Premises only for the purpose related to its water purification equipment
and precision cleaning equipment business with offices on the second floor,
center [Four Thousand Seven Hundred Four (4,704) square feet] and production on
the first floor, south end [Six Thousand Six Hundred Twenty-Five (6,625) square
feet] and for other services and purposes reasonably incident thereto.

         12.2 In its use of the Leased Premises, Tenant shall comply with all
statutes, ordinances and regulations applicable to the use thereof, including,
without limiting the generality of the foregoing, the Zoning Ordinances of the
City of Manchester, New Hampshire, as now in effect or as hereafter amended.

         12.3 Tenant shall not injure or deface, or commit waste with respect to
the Leased Premises nor occupy or use the Leased Premises, or permit or suffer
any part thereof to be occupied used, for any unlawful or illegal business, use
or purpose, nor for any business, use or purpose deemed to be disreputable or
extra-hazardous, nor in such manner as to constitute a nuisance of any kind, nor
for any purpose nor in any manner in violation of any present or future laws,
rules, requirements, orders, directions, ordinances or regulations of any
governmental or lawful authority including Boards of Fire Underwriters. Tenant
shall, immediately upon the discovery of any such unlawful illegal, disreputable
or extra-hazardous use, take, at its own cost and expense, all necessary steps,
legal and equitable, to compel the discontinuance of such use and to oust and
remove the subtenants, occupants or other persons guilty of such unlawful, 
illegal, disreputable or extra-hazardous use.

         12.4  Tenant shall procure any licenses or permits required by any use
of the Leased Premises by Tenant.

ARTICLE XIII - HAZARDOUS WASTE OR SUBSTANCES

         13.1 Except for the Tenant's use of the Leased Premises as described
and permitted in Article XII above ("Tenant's Use"), Tenant shall not use the
Leased Premises for the generation, storage or treatment of hazardous waste or
substances, and hereby certifies that its operations or other use of the Leased
Premises will not involve same. For purposes of this lease, the term "Hazardous
Waste or Substances" is defined by cumulative reference to the following sources
as amended from time to time: (1) The Resource Conservation and Recovery Act of
1976, 42 USC ~901 et seq (RCRA); (2) Comprehensive Environmental Response,
Compensation and Liability Act of 1980, 42 U.S.C. ~9601 et seq.; (3) Superfund
Amendments and Reauthorization Act of 1986, 42 U.S.C. ~6901 et seq; (4) CPA
Federal Regulations promulgated thereunder and codified in 40 C.F.R. Parts
260-265 and Parts 122-124; (5) New Hampshire R.S.A. Ch 147 and 147-A; (6) New
Hampshire Regulations promulgated thereunder by any Agency or Department of the
state.

         13.2 Tenant agrees not to release or dispose of any Hazardous Waste or
Substances at the Leased Premises, nor to permit the same, at any time other
than in accordance with ordinary business practice and in compliance with
applicable laws, rules, ordinances and regulations. Tenant covenants to strictly
comply with all the requirements of all environmental laws and to immediately
notify Landlord of the presence (except as permitted in conjunction with
Tenant's Use), release, discharge, spill or threat of release, discharge or
spill of any Hazardous Waste or Substance at or from the Leased Premises or any
notice or claim received by it of any violation of any environmental laws.

         13.3 Tenant warrants and acknowledges that at no time have funds been
expended from the State of New Hampshire's hazardous waste cleanup fund
established under RSA 147-B with respect to any of Tenant's property located
within New Hampshire which would entitle the State to also called superlien
under RSA 147-B: 10 III. Tenant also acknowledges same with respect to similar
laws of any other state which liens might possibly affect the Leased Premises.
The warranty of this section will survive the expiration or termination of this
Lease.

<PAGE>   10
         13.4 To the fullest extent permissible according to law, and without
limiting other rights or remedies of Landlord, Tenant unconditionally,
absolutely and irrevocably agrees to defend, hold harmless and indemnify
Landlord and the holder of a mortgage lien on the Building (the "Mortgagee") and
their officers, employees, agents and contractors (the "Indemnified Parties")
against all damages, claims, costs, losses, liabilities and expenses, including
attorney's fees and expenses, suffered or incurred by the Indemnified Parties
due to the existence at any time of any Hazardous Waste or Substances (except as
permitted in conjunction with Tenant's Use) at the Leased Premises or the
Building, or by any other person for whose conduct Tenant is responsible,
including without limitation, any claims, costs, losses, liabilities and
expenses arising from the violation of any environmental laws or the imposition
by any local, state or federal government or governmental agency, department or
authority of a lien, attachment or other encumbrance on any part of the
Building. The foregoing indemnification shall survive the expiration or the
termination of this Lease.

         13.5 If the presence or release of Hazardous Waste or Substances at or
from the Leased Premises or the Building has resulted in contamination of any
portion of the Leased Premises or the Building resulting in a level of
contamination greater than the levels permitted or established by any
governmental agency having jurisdiction, then Tenant shall promptly take any and
all action necessary to clean up such contamination to the extent required by
any governmental authority having jurisdiction or as a condition to the issuance
or continuing effectiveness of any governmental approval or any insurance policy
that relates to the Building or the use thereof. Tenant shall further be solely
responsible for, and shall defend, indemnify and hold the Indemnified Parties
harmless from and against all damages, claims, costs, losses, liabilities and
expenses, including attorney's fees and expenses, of whatever nature, on account
of, arising out of or in connection with any removal, clean up or restoration
work which is required to return the Leased Premises or the Building and any
other affected property of whatever nature to their condition existing prior to
the presence or release of the Hazardous Waste or Substances.

         13.6 Landlord has no knowledge of the existence of any Hazardous Waste
or Substance in the Leased Premises. To the fullest extent permissible according
to law, and without limiting other rights or remedies of Tenant, Landlord
unconditionally, absolutely and irrevocably agrees to defend, hold harmless and
indemnify Tenant and its officers, employees, agents and contractors (the
"Indemnified Parties") against all damages, claims, costs, losses, liabilities
and expenses, including attorney's fees and expenses, suffered or incurred by
the Indemnified Parties due to the existence of any Hazardous Waste or
Substances at the Leased Premises prior to the term of this lease, in the
remaining portion of the Building arising solely out activities by Landlord, of
any Hazardous Waste or Substances, including without limitation, any claims,
costs, losses, liabilities and expenses arising from the violation of any
environmental laws or the imposition by any local, state or federal government
or governmental agency, department or authority of a lien, attachment or other
encumbrance on any part of the Building. The foregoing indemnification shall
survive the expiration or the termination of this Lease.

         13.7 If, as the result of the activities of Landlord, the presence or
release of Hazardous Waste or Substances at or from the Leased Premises or the
Building has resulted in contamination of any portion of the Leased Premises or
the Building resulting in a level of contamination greater than the levels
permitted or established by any governmental agency having jurisdiction, then
Landlord shall promptly take any and all action necessary to clean up such
contamination to the extent required by any governmental authority having
jurisdiction or as a condition to the issuance or continuing effectiveness of
any governmental approval or any insurance policy that relates to the Building
or the use thereof.

ARTICLE XIV - ASSIGNMENT; SUBLEASING

         14.1 Tenant shall not, voluntarily, by operation of law, or otherwise,
assign, transfer, mortgage, pledge or encumber this Lease or sublease the Leased
Premises or any part thereof, or grant a right to any person other than Tenant,
its employees, agents, servants and invitees to occupy or use the Leased
Premises or any portion thereof, without the express prior written consent of
Landlord. Any attempt to do any of the foregoing without such written consent
shall be null and void and of no affect, and shall further constitute a material
default under this Lease. If Tenant so requests Landlord's consent, said request
shall be in writing specifying the duration of said desired sublease or
assignment, the date same is to occur, the exact location of the space affected
thereby and the proposed rentals on a square foot basis chargeable thereunder,
and shall be submitted to Landlord at least sixty (60) days in 
<PAGE>   11


advance of the date on which Tenant desires to make such assignment or sublease
or allow such occupancy or use. Upon such request, Landlord may, in its sole
discretion, (i) deny such consent, or (ii) grant such consent subject to
Landlord's approval of the assignee, transferee, subtenant or mortgagee, or
(iii) elect to terminate this Lease, or (iv) suspend this Lease as to the space
to be affected by such assignment, sublease or other event specified above for
the duration specified by Tenant in its notice, in which event Tenant will be
relieved of all obligations hereunder as to such space during such suspension,
including a suspension of the rent hereunder in proportion to the portion of the
Leased Premises affected thereby (but after said suspension, if the suspension
is not for the full term hereof, Tenant shall once again become liable hereunder
as to the applicable space).

         14.2 Tenant shall, despite any permitted assignment or sublease, remain
directly and primarily liable for the performance of all of the covenants,
duties and obligations of Tenant hereunder, and Landlord shall be permitted to
enforce the provisions of this Lease against Tenant or any assignee: or
sublessee without demand upon or proceeding in any way against any other person.

         14.3 Consent by Landlord to a particular assignment or sublease shall
not be deemed a consent to any other subsequent transaction. If this Lease is
assigned or if the Leased Premises are subleased without the permission of
Landlord, then Landlord may nevertheless collect rent from the assignee or
sublessee and apply the net amount collected to the rent payable hereunder, but
no such transaction or collection of rent or application thereof by Landlord
shall be deemed a waiver of any provision hereof or a release of Tenant from the
performance of the obligations of the Tenant hereunder.

         14.4 All cash or other proceeds of any assignment, sale or sublease of
Tenant's interest in this Lease, whether consented to by Landlord or not, shall
be paid to Landlord notwithstanding the fact that such proceeds exceed the rent
called for hereunder, and Tenant hereby assigns to Landlord all rights it might
have or ever acquire in such proceeds.

 ARTICLE XV - TAXES AND ASSESSMENTS

         15.1 Beginning in Lease Year 2, Tenant shall pay, in addition to Base
Rent and other charges, an amount equal to Tenant's Proportionate Share of the
increase in "Real Estate Taxes" (hereinafter defined) from the amount of Real
Estate Taxes for the 1995 tax year and levies and charges and governmental
impositions, duties and charges of like kind and nature which are or may during
the term of this Lease be charged, laid, levied or imposed upon or become a lien
or liens upon the Building or any part thereof, or upon any buildings or
appurtenances thereto or any parts thereof, or which may become due and payable
with respect thereto and any and all taxes charged, laid or levied in addition
to the foregoing under or by virtue of any present or future laws, requirements,
rules, orders, directions, ordinances or regulations of the United States of
America, the State of New Hampshire, County of Hillsborough, City of Manchester
government, or of any other municipal government or lawful authority whatsoever.
All such duties and charges, including Real Estate Taxes, are referred to herein
as "Taxes". Tenant's Proportionate Share of Real Estate Taxes for Lease Year 1
is calculated to be $4,764 per year, which amount is included in the Base Rent
stated in Article TV.

         15.2 "Real Estate Taxes" means all real estate taxes, sewer taxes, and
any other charges made by a public authority which upon assessment or failure of
payment become a lien or liens upon the Building or any part thereof, or upon
any buildings or appurtenances thereto, or any parts thereof, or which may
become due and payable with respect thereto. If any betterment assessments are
payable by law in installments, said betterment assessments are deemed payable
not for the period in which the same are assessed but in installments for the
periods in which the installments thereof are payable. Peal estate taxes shall
not include any franchise, estate, inheritance, succession, capital levy or
transfer tax of Landlord or any income tax of Landlord.

         15.3 Beginning in Lease Year 2, Tenant shall pay to Landlord along with
each installment of rent, an amount equal to one-twelfth (1/12th) of Tenant's
Proportionate Share of the increase of the Taxes from the 1995 tax year for the
current tax year, if the amount thereof is known, or of an estimate of said
increase, if the amount thereof for the current tax year is not known. Upon
receipt by Landlord of the final tax bill for any tax year during the term of
this Lease, Landlord shall give Tenant notice of the total amount of said
increase in Taxes paid by 


<PAGE>   12

landlord for such tax year. If the actual amount of Tenant's Proportionate Share
of said increase in Taxes with respect to such tax year exceeds the aggregate
amount previously paid by Tenant, Tenant shall pay to Landlord the deficiency
within fifteen (15) days following notice from Landlord. If the aggregate amount
previously paid by Tenant with respect thereto exceeds Tenant's Proportionate
Share of said increase in Taxes for such tax year, then, at Landlord's election,
such surplus (net of any amounts then owing by Tenant to Landlord) shall be
credited against the next ensuing installment of any such cost due hereunder by
Tenant. Periodically, during the Term of this Lease, Landlord shall have the
right to estimate Tenant's Proportionate Share of said increase in Taxes for the
next tax year (determined by Landlord) of the term of this Lease, whereupon
Tenant shall pay Landlord such revised amount as set forth in the first sentence
of this Section 15.3.

         15.4 Tenant shall also punctually pay and discharge all taxes which are
or may during the term of this Lease be charged, laid, levied or imposed upon or
become a lien upon any personal property of Tenant attached to or used in
connection with Tenant's business conducted on the Leased Premises which
personal property constitutes a fixture. Nothing herein contained requires
Tenant to pay any taxes on the rent reserved to Landlord hereunder.

         15.5 Landlord, at its option, may, but shall not be obligated to,
contest or review by any appropriate proceedings, and at Landlord's expense, any
tax, charge or other governmental imposition aforementioned which shall not be
contested or reviewed as aforesaid by Tenant, and Tenant shall promptly join
with Landlord in such contest or review if Landlord so requests. Any abatement
in such taxes shall be reflected in the amount of taxes to be paid by Tenant the
following year pursuant to this Article XV.

ARTICLE XVI - MECHANIC'S LIEN

         16.1 In the event of the filing in the Hillsborough County Registry of
Deeds of any notice of a builder's, supplier's or mechanic's lien on the Leased
Premises or the Building arising out of any work performed by or on behalf of
Tenant (excluding any work performed by Landlord), Tenant shall cause without
delay proper proceedings to be instituted to test the validity of die lien
claimed, and before the end of the term to discharge the same by the posting of
bond or otherwise; and during the pendency of any such proceeding, Tenant shall
completely defend and indemnify Landlord against any such claim or lien and all
costs of such proceedings wherein the validity of such lien is contested by
Tenant, and during the pendency of such proceeding such lien may continue until
disposition of such proceeding, and after disposition thereof, Tenant shall
cause said lien to be released and discharged.

ARTICLE XVII - EMINENT DOMAIN

         17.1 If the Leased Premises is lawfully condemned or taken by any
public authority either in its entirety or in such proportion that it is no
longer suitable for the intended use by Tenant, then this Lease will
automatically terminate without further act of either party hereto on the date
when possession of the Leased Premises is taken by such public authority, and
each party hereto will be relieved of any further obligation to the other except
that Tenant shall be liable for and shall promptly pay to Landlord any rent or
other payments due hereunder then in arrears or Landlord shall promptly rebate
to Tenant a pro rata portion of any rent or other such payments paid in advance.
In the event the proportion of the Leased Premises so condemned or taken is such
that the Leased Premises is still suitable for its intended use by Tenant, this
Lease will continue in effect in accordance with its terms and a portion of the
rent and other payments due hereunder will abate equal to the proportion of the
rental value of the Leased Premises so condemned or taken. In either of the
above events, the award for the property so condemned or taken will be payable
solely to Landlord without apportionment to Tenant, except that Tenant shall be
entitled to a separate award, if any, for moving expenses.

ARTICLE XVIII - LIABILITY

         18.1 Except for injury or damage caused by the gross negligence or
willful misconduct of Landlord, its servants or agents, Landlord shall not be
liable for any injury or damage to any person happening on or about the Leased
Premises or the Building or for any injury or damage to the Leased Premises or
to any property of Tenant or to any property of any third person, firm,
association, or corporation on or about the Leased Premises or the

<PAGE>   13

Building. Tenant shall, except for injury or damage caused as aforesaid, defend
(with counsel reasonably acceptable to Landlord), indemnify and hold Landlord
harmless from and against any and all liability and damages, costs and expenses,
including reasonable attorneys' fees, and from and against any and all suits,
claims and demands of any kind or nature whatsoever, by and on behalf of any
person, firm, association or corporation arising out of or based upon any
incident, occurrence, injury or damage which happens or may happen on or about
the Leased Premises and from and against any matter or thing growing out of the
condition, maintenance, repair, alteration, use, occupation or operation of the
Leased Premises or the installation of any property therein or the removal of
any property therefrom.

ARTICLE XIX - RULES AND REGULATIONS

         19.1 Tenant, its servants, employees, agents, visitors, invitees, and
licensees, shall observe faithfully and comply strictly with the Rules and
Regulations set forth in Exhibit C hereto, and shall abide by and conform to
such further rules and regulations as Landlord may from time to time reasonably
make, amend or adopt, after Tenant receives a copy thereof.

ARTICLE XX - LANDLORD'S INSURANCE

         20.1 In the event of loss, Landlord shall promptly initiate action to
effect a settlement with the insurer. Tenant shall cooperate with Landlord and
any mortgagee in connection with the proceeding and collection of claims, and
shall execute and deliver to Landlord such proofs of loss, releases and other
instruments as may be necessary to settle any such claims and obtain the
proceeds thereof, and in the event Tenant fails or neglects to so cooperate or
to execute and deliver any such instrument, Landlord may, as the agent or
attorney in fact of Tenant, execute and deliver any such instrument, and Tenant
hereby nominates and appoints Landlord the proper and legal attorney in fact of
Tenant for such purpose, hereby ratifying all that Landlord may lawfully do as
such attorney in fact.

         20.2 If and to the extent permitted without prejudice to any rights of
Landlord under the applicable insurance policies, Tenant shall be held free and
harmless from liability for loss or damage to the Leased Premises by fire, the
extended coverage perils, sprinkler leakage, vandalism and malicious mischief if
and to the extent actually insured against, whether or not such loss or damage
is the result of the negligence of Tenant, its employees or agents. This
subsection does not impose any added obligation or expense upon Landlord nor
require that it carry any insurance of any kind and is to be construed only as a
limitation upon the rights of the insurance carriers to subrogation.

ARTICLE XXI - TENANT'S INSURANCE

         21.1 Tenant shall, from the Delivery of Possession of the Leased
Premises, even if such date precedes the commencement of the term hereof, and
throughout the term hereof procure and carry at its own expense comprehensive
liability insurance on the Leased Premises with an insurance company authorized
to do business in New Hampshire and acceptable to Landlord. Such insurance will
be carried in the name of and for the benefit of Tenant and Landlord ; will be
written on an "occurrence" basis; and shall provide coverage of at least One
Million Dollars ($1,000,000) in case of death of or injury to one person, Three
Million Dollars ($3,000,000) in case of death of or injury to more than one
person in the same occurrence, and One Million Dollars (S1,000,000) in case of
loss, destruction or damage to property. If applicable, Tenant shall comply with
the requirements of the Boilers and Unfired Pressure Vessels Law (RSA 157-A),
and in such event the policy or policies referred to above shall contain an
endorsement providing pressure vessels insurance coverage and naming Landlord as
an additional insured. Tenant shall furnish to Landlord a certificate of such
insurance which must provide that the insurance indicated therein will not be
canceled without at least ten (10) days written notice to Landlord.

         21.2 During any period or periods of construction by Tenant on the
Leased Premises, the construction of which (a) is of a type to which Builder's
Risk Insurance is applicable and (b)requires the-advance written approval of
Landlord pursuant to Article M hereof, Tenant shall obtain and maintain in
effect standard Builder's Risk Insurance written on a completed value basis,
including extended coverage, and utilizing a maximum value at

<PAGE>   14


date of completion not less than the greater of (y) the aggregate contract price
or prices for the construction of such facilities or (z) the amount which may be
required by a mortgagee which is financing such construction. Such insurance
shall be obtained from an insurance company authorized to do business in New
Hampshire and acceptable to Landlord, and Lessee shall furnish to Landlord a
certificate of such insurance which shall provide that the insurance indicated
therein shall not be canceled without at least ten (10) days written notice to
Landlord. If such construction by Tenant is of a type to which Builder's Risk
Insurance is not applicable, Tenant shall provide the necessary additional
coverage under the policies referred to in this ARTICLE XXI.

         21.3 Tenant shall procure and continue in force during the term hereof,
all-risk insurance which contains fire and extended coverage on a full value,
repair or replacement basis upon facilities, machinery, equipment and
appurtenances constructed, erected or installed on or in the Leased Premises by
Tenant and which have or: may become the property of Landlord pursuant hereto.
The policies evidencing such insurance must provide that loss, if any, payable
thereunder will be payable to Landlord and/or Tenant and/or mortgagee of the
Leased Premises or the Building as their respective interests may appear, and
all such policies together with evidence of payment of the premiums thereon will
be delivered to Landlord and/or any such mortgagee. All such policies must be
taken in such responsible companies authorized to do business in New Hampshire
as Landlord shall approve (which approval shall not be unreasonably withheld)
and must be in form satisfactory to Landlord. Upon receipt of a copy of notice
of cancellation of any insurance which is the responsibility of Tenant
hereunder, Landlord may pay the premiums necessary to reinstate the same. The
amount so paid will constitute Additional Rent payable by Tenant at the next
rental payment date. Payment of premiums by Landlord will not be deemed a waiver
or release by Landlord of the default by Tenant in failing to pay the same or of
any action which Landlord may take hereunder as a result of such default. Tenant
shall neither violate, nor allow its agents or employees to violate any of the
terms, conditions and provisions of such policies.

         21.4 If and to the extent permitted without prejudice to any rights of
Tenant under the applicable insurance policies, Landlord shall be held free and
harmless from liability for loss or damage to personal property of Tenant in the
Leased Premises by fire, the extended coverage perils, sprinkler leakage,
vandalism and malicious mischief if and to the extent actually insured against,
whether or not such loss or damage is the result of the negligence of Landlord,
its employees or agents. This subsection does not impose any added obligation or
expense upon Tenant nor require that it carry any insurance of any kind and is
to be construed only as a limitation upon the rights of the insurance carriers
to subrogation.

ARTICLE XXII - DESTRUCTION OR DAMAGE

         22.1 In the event that the Leased Premises, as it exists at the
beginning of the term hereof, is totally destroyed by fire or other casualty
insured against, or is so damaged that repairs and restoration cannot, in the
opinion of Landlord in its sole discretion, be accomplished within a period of
one hundred twenty (120) days from the date of such destruction or damage, this
Lease will automatically terminate without further act of either party hereto,
and each party shall be relieved of any further obligation to the other except
for the rights and obligations of the parties under ARTICLES XX and XXI hereof,
and except that Tenant shall be liable for and shall promptly pay Landlord any
Rent then in arrears or Landlord shall promptly rebate to Tenant a pro rata
portion of any Rent paid in advance. In the event that the Leased Premises is so
damaged that repairs and restoration can be accomplished within a period of one
hundred twenty (120) days from the date of such destruction or damage, this
Lease will continue in effect in accordance with its terms; such repairs and
restoration will, unless otherwise agreed by Landlord and Tenant, be performed
as closely as practicable to the original specifications (utilizing therefor the
proceeds of the insurance applicable thereto without any apportionment thereof
for damages to the leasehold interest created by this Lease), and until such
repairs and restoration have been accomplished, a portion of the rent will abate
equal to the proportion of the Leased Premises rendered unusable by the damage.
Landlord's obligation to restore, replace or rebuild such facilities will not
exceed in amount the sum of the insurance proceeds paid to it and/or released to
it by any mortgagee with which settlement was made. In the event the Leased
Premises may be repaired and/or restored within the aforementioned one hundred
twenty (120) day period, but the cost of such repair or restoration exceeds the
available insurance proceeds, at Landlord's discretion, this Lease will be
terminated in which event the rights and duties of the parties shall be governed
by the first sentence of this Section 22.1. Tenant shall execute and deliver to
Landlord all instruments and documents necessary to evidence the fact

<PAGE>   15

that the right to such insurance proceeds is vested in Landlord. In the event of
damage or destruction, partial or total, to or of machinery, equipment and
appurtenances constructed or installed on or in the Leased Premises by Tenant,
Tenant, provided it then be in full compliance with ARTICLE XXI hereof, will be
entitled to receive an apportionment of the insurance proceeds in accordance
with the relative damage or destruction to or of (a) the Leased Premises as it
exists at the beginning of the term hereof and (b) the machinery, equipment and
appurtenances, if any, constructed or installed on or in the Leased Premises by
Tenant at its expense after the beginning of the term hereof and which could
have been removed by Tenant pursuant to ARTICLE X hereof. Notwithstanding
anything contained herein to the contrary, in the event that the damage to the
Leased Premises results from the fault or negligence of Tenant, its agents,
employees, licensees or invitees, Tenant shall not be entitled to any abatement
or reduction of any rent or other sums due hereunder, and such damage shall be
repaired by Tenant, or at Landlord's option by Landlord at Tenant's expense.

ARTICLE XXIII - REPOSSESSION BY LANDLORD

         23.1 At the expiration of this Lease or upon the earlier termination of
this Lease for any cause herein provided for, Tenant shall peaceably and quietly
quit the Leased Premises and deliver possession of the same to Landlord together
with the improvements thereon at the beginning of the term hereof and all
improvements constructed thereon by Tenant which are not removed pursuant to the
terms hereof, and all machinery, equipment and appurtenances installed therein
which have become part of the Leased Premises, or which are not to be removed
pursuant to ARTICLE X hereof. At the time of delivery of possession to Landlord
at the expiration of this Lease any and all machinery, equipment and
appurtenances constructed or installed on or in the Leased Premises by Tenant at
its expense after the beginning of the term hereof, which constitute fixtures
and which have become the property of Landlord pursuant to ARTICLE X hereof will
be free and clear of any mortgage, lien, pledge or other encumbrance or charge.
Landlord acknowledges that Tenant intends to install the equipment listed on
Exhibit D hereto and further acknowledges that said equipment shall remain the
sole property of Tenant and shall not become fixtures. Tenant shall have the
absolute right to remove the equipment listed on Exhibit D.

ARTICLE XXIV - MORTGAGE LIEN

         24.1 This Lease and all rights of Tenant hereunder are and will remain
subject and subordinate to the lien of (a) any mortgage(s) constituting a lien
on the Building, or any part thereof, at the date hereof, and b) the lien of any
mortgage(s) hereafter executed to a person, bank, trust company, insurance
company or other recognized lending institution to provide permanent financing
or refinancing of the facilities on the Building, and (c) any renewal,
modification, consolidation or extension of any mortgage or deed of trust
referred to in clause (a) or b). Tenant shall, upon demand at any time or times,
execute, acknowledge and deliver to Landlord, any and all instruments that may
be necessary or proper to subordinate this Lease and all rights of Tenant here
under to the lien of any mortgage, deed of trust or other instrument referred to
in clause (b) or clause (c) of the preceding sentence, and, in the event that
Tenant shall fail or neglect to execute, acknowledge and deliver any such
subordination instrument notwithstanding its receipt of a reasonable
subordination, nondisturbance and attornment agreement (see below) from said
mortgagee, Landlord, in addition to any other remedies, may, as the agent or
attorney-in-fact of Tenant, execute acknowledge and deliver the same, and Tenant
hereby nominates, constitutes and appoints Landlord as Tenant's proper legal
attorney-in-fact for such purposes; provided, however, that the subordination of
this Lease shall be conditioned upon the execution and delivery by the mortgagee
or trustee of an agreement (i) that so long as Tenant is not in default under
the terms of this Lease the mortgagee or trustee, or any person succeeding to
the rights of the mortgagee or trustee, or any purchaser at a foreclosure sale
under said mortgage or deed of trust, shall not disturb the peaceful possession
of Tenant hereunder, and (ii) that the proceeds of insurance policies received
by it in settlement of losses under insurance policies held by it will be
applied to the cost of repairs and restoration in those instances in which
Landlord is obligated to repair and restore pursuant to the provisions hereof.

         24.2 Tenant shall execute and acknowledge a certificate containing such
information as may be reasonably requested for the benefit of Landlord, any
prospective purchaser or any current or prospective mortgagee of the Building
within ten (10) days of receipt of same. In the event Tenant fails to deliver
such certificate to Landlord, Tenant irrevocably appoints Landlord as Tenant's
attorney-in-fact to execute the same.

<PAGE>   16

ARTICLE XXV - DEFAULT

         25.1 In the event that (a) any installment of Rent or Additional Rent
is not paid within ten (10) days after the same is due and payable, or b) Tenant
defaults in the performance or observance of any other covenant or condition in
this Lease and such default remains unremedied for ten (10) days after written
notice thereof has been given or sent to Tenant by Landlord, or (c) any warranty
or representation made by Tenant herein proves to be false or misleading, or (d)
Tenant makes an assignment for the benefit of creditors, is generally not paying
its debts as such debts become due, a custodian is appointee or takes possession
of its assets other than a trustee, receiver or agent appointed or authorized to
take charge of less than substantially all of the property of Tenant for the
purpose of enforcing a lien against such property, commences any proceeding
relating to Tenant or any substantial part of its property arrangement,
readjustment of debt, dissolution or liquidation law or statute of any
jurisdiction whether now or hereafter in effect, or there is commenced against
Tenant any such proceeding which remains undismissed for a period of sixty (60)
days, or any order approving the petition in any such proceeding is entered, or
Tenant by any act indicates its consent to, or acquiescence in, any such
proceeding or the appointment of any receiver or trustee for Tenant or any
substantial part of its property, or suffers any such receivership or
trusteeship to continue undischarged for a period of sixty (60) days, or any
party holding a security interest in any of Tenant's fixtures or personal
property of any nature whatsoever that are located on the Leased Premises
institutes or gives notice of foreclosure against any such property, or (e)
Tenant shall have assigned or sublet the Leased Premises without the prior
written consent of Landlord, or (f) Tenant shall abandon or vacate or shall
commence to abandon or vacate the Leased Premises or any substantial portion of
the Leased Premises or shall remove or attempt to remove, without the prior
written consent of Landlord, all or a substantial portion of Tenant's goods,
wares, equipment, fixtures, furniture, or other personal property, or (g) the
dissolution of Tenant, in any of such events, Landlord may immediately or at any
time thereafter and without demand or notice enter upon the Leased Premises or
any part thereof in the name of the whole and repossess the same as of
Landlord's former estate and expel Tenant and those claiming through or under
Tenant and remove their effects forcibly if necessary, without being deemed
guilty in any manner of trespass and without prejudice to any remedies which
might otherwise be used for arrears of rent or preceding breach of covenant, and
upon such entry this Lease will terminate, and in case of such termination or in
case of termination under the provisions of statute by reason of the default of
Tenant, Tenant shall remain and continue liable to Landlord in an amount equal
to the total Rent reserved for the balance of the term plus all additional Rent
reserved for the balance of such term less the net amounts (after deducting the
expenses of repair, renovation or demolition) which Landlord realizes, or with
due diligence should have realized, from the reletting of the Leased Premises,
plus all costs associated with the termination of the Lease, including
Landlord's reasonable attorneys' fees. As used in this Section, the term
"Additional Rent" means the value of all considerations other than Base Rent
agreed to be paid or performed by Tenant hereunder, including, without limiting
the generality of the foregoing, taxes, assessments, maintenance charges, and
insurance premiums. Landlord will have the right from time to time to relet the
Leased Premises upon such terms as it deems fit, and if a sufficient sum is not
thus realized to yield the net rent required under this Lease, Tenant shall
satisfy and pay all deficiencies as they may become due during each month of the
remaining term of this Lease. Nothing herein contained will be deemed to require
Landlord to await the date on which this Lease, or the term hereof, would have
expired had there been no default by Tenant, or no such termination or
cancellation. Landlord's rights and remedies under this Lease are distinct,
separate and cumulative remedies, and no one of them, whether or not exercised
by Landlord, will be deemed to be in exclusion of any of the others herein or by
law or equity provided. Nothing contained in this Section will limit or
prejudice the right of Landlord to prove and obtain, in proceedings involving
the bankruptcy or insolvency) of, or a composition with creditors by, Tenant the
maximum allowed by any statute or rule of law at the time in effect.

ARTICLE XXVI - ACCESS TO LEASED PREMISES

         26.1 Landlord of its representatives shall have free access to the
Leased Premises at all times in cases of emergency and at reasonable intervals
during normal business hours for the purpose of inspection, or for the purpose
of showing the Leased Premises to prospective purchasers or tenants, or for the
purpose of making repairs which Tenant is obligated to make hereunder but has
failed or refused to make; provided, that (with the exception of emergency
situations), Landlord shall not unreasonably interfere with Tenant's business.
The preceding sentence 

<PAGE>   17

does not impose upon Landlord any obligation to make repairs. During the ninety
(90) day period preceding the expiration of this Lease, Landlord may keep
affixed to any suitable part of the outside of the building on the Leased
Premises a notice that the Leased Premises is for sale or rent.

ARTICLE XXVII - NOTICES

         27.1 Any written notice, request or demand required or permitted by
this Lease will, until either party notifies the other in writing of a different
address, be properly given if hand delivered or sent by certified or registered
first class mail, postage prepaid, and addressed as follows:

If to Landlord:                 Mr. John C. Madden
                                Five-Forty North Associates
                                c/o JCM Management Company, Inc.
                                540 North Commercial Street
                                Manchester, NH 03101

With a copy to:                 Karen S. McGinley, Esq.
                                Devine, Millimet & Branch, P.A.
                                111 Amherst Street, P.O. Box 719
                                Manchester, NH 03105-0719

If to Tenant:                   Mr. James J. Andrus
                                Kyzen Corporation
                                13 Hampshire Drive
                                Hudson, NH 03051


With a copy to:                 Mr. Ben Wolfley
                                Kyzen Corporation
                                430 Harding Industrial Drive
                                Nashville, TN 37211

ARTICLE XXVIII - SIGNS; EXTERIOR APPEARANCE; PYLON

         28.1 Tenant shall not, without Landlord's prior written consent,
install any exterior lighting, decorations, paintings, or the like; or erect or
install any signs, banners, window or door lettering, placards, decorations or
advertising media of any type that can be viewed from the exterior of the Leased
Premises. Tenant may install a sign on the outside of the building to identify
its business and logo in a style and coloring consistent with the other Tenant
signs and shall be no larger than ten inches by thirty-six inches (10" X 36").
All signs, banners, lettering, placards, decorations and advertising media shall
conform in all respects to the requirements, if any, of all applicable laws,
codes and ordinances and to the sign criteria established by Landlord for the
Building from time to time in the exercise of its sole discretion, and shall be
subject to the prior written approval of Landlord as to construction, method of
attachment, size, shape, height, Lighting, color and general appearance. All
signs shall be kept in good condition and in proper operating order at all
times. In the event that Tenant enters into a co-venture with another company,
Tenant shall be permitted to add an additional sign at the building entrance
identifying such party, subject to the conditions set forth in this Section
28.1. Upon the expiration or earlier termination of this Lease, Tenant shall
remove the sign and restore the surface to which the sign was attached to its
original condition at Tenant's expense. In the event Tenant fails to remove the
sign within three (3) days from expiration or earlier termination of this Lease,
the sign shall become the property of Landlord without any credit or
compensation to Tenant, and Landlord may, but is not obligated to, remove and
store or dispose of the sign and Tenant shall be liable to Landlord for all
costs incurred by Landlord in connection therewith. Tenant shall indemnify and
hold Landlord harmless from all loss, damage, cost, expense and liability in
connection with Such removal, storage or disposal.

<PAGE>   18


ARTICLE XXIX - SHORT FORM RECORDING

         29.1 If required by the applicable statute, there shall be recorded in
the Hillsborough County Registry of Deeds a Notice of this Lease that complies
in content and form with New Hampshire RSA Section 477:7-a. Landlord and Tenant
shall execute and deliver a Notice of Lease in such form for such purpose. In
the event of termination, cancellation or assignment of this Lease prior to the
expiration of the term hereof, Landlord and Tenant shall execute and deliver, in
recordable form, an instrument setting forth such termination, cancellation or
assignment.

ARTICLE XXX - NO BROKER

         30. 1 The parties covenant that no broker was involved in any capacity
in bringing about the relationship evidenced by this Lease, except for Kanteres
Real Estate, Inc., whose fee, if any, is the responsibility of Landlord; and
further agree that if any claim on behalf of any broker or agent is made or
upheld, then the party against or through whom such claim is made shall defend
(with counsel reasonably acceptable to the other party), indemnify and hold the
other harmless against any damages, costs or expenses in any way attributable to
such claim, including without limitation reasonable attorney's fees.

ARTICLE XXXI - WARRANTIES AND REPRESENTATIONS OF TENANT

         31.1 Tenant warrants and represents to Landlord that Tenant's entrance
into this Lease does not violate any other contracts, agreements, Leases or any
other arrangements of any nature whatsoever that Tenant has with any third
parties.

         31.2 Tenant represents and warrants to Landlord that Tenant (i) is a
corporation duly organized, validly existing under the laws of the state of its
incorporation and in good standing under the laws of the state of its
incorporation and the laws of the State of New Hampshire, (ii) has paid all
franchise and other taxes, if any, required to maintain the corporate existence
of Tenant, and (iii) is not the subject of voluntary or involuntary proceedings
for the forfeiture of the Articles of Incorporation of Tenant for its
dissolution.

ARTICLE XXXII - SUCCESSION

         32.1 This Lease is binding upon and will inure to the benefit of the
heirs, executors, administrators, successor and permitted assigns of the parties
hereto.

ARTICLE XXXIII - WAIVER

         33.1 Any consent, express or implied, by Landlord to any breach by
Tenant of any covenant or condition of this Lease will not constitute a waiver
by Landlord of any prior or succeeding breach by Tenant of the same or any other
covenant or condition of this Lease. Acceptance by Landlord of rent or other
payment with knowledge of a breach of or default under any condition hereof by
Tenant will not constitute a waiver by Landlord of such breach or default.

ARTICLE XXXIV - GOVERNING LAW

         34.1 This Lease will be construed and interpreted in accordance with
the laws of the State of New Hampshire.

ARTICLE XXXV - COUNTERPARTS

         35.1 This Lease may be executed in two (2) or more counter-parts, each
of which will be deemed an original and all collectively but one and the same
agreement.
<PAGE>   19
ARTICLE XXXVI - MODIFICATION; ENTIRE AGREEMENT

         36.1 This Lease contains and embraces the entire agreement between the
parties hereto and no part of it may be changed, altered, amended, modified,
limited or extended orally or by agreement between the parties unless such
agreement is expressed in writing and signed by Landlord and Tenant or their
respective successors in interest.

ARTICLE XXXVII - SECTION HEADINGS

         37.1 The headings at the beginning of each of the Sections in this
Lease are solely for purposes of convenience and identification and are not to
be deemed or construed to be part of this Lease.

ARTICLE XXXIII - SEVERABILITY

         38.1 If any term, clause or provision of this Lease is judged to be
invalid and/or unenforceable, the validity and/or enforceability of any other
term, clause or provision in this Lease will not be affected thereby.

         IN WITNESS WHEREOF, the parties execute this Lease as of the day and
year first above written.

FIVE-FORTY NORTH ASSOCIATES
("Landlord")


By: /s/ John C. Madden
    --------------------------------------
    John C. Madden, General Partner


KYZEN CORPORATION
("Tenant")


By: /s/ James J. Andrus
    --------------------------------------
    James J. Andrus,-Vice President