EXHIBIT B



THESE  SECURITIES HAVE NOT BEEN  REGISTERED  UNDER THE SECURITIES ACT OF 1933 OR
ANY STATE  SECURITIES  ACTS OR LAWS,  AND HAVE BEEN  ISSUED AND SOLD IN RELIANCE
UPON  EXEMPTIONS  FROM THE  REGISTRATION  REQUIREMENTS  OF SUCH  ACTS AND  LAWS,
INCLUDING  BUT NOT LIMITED TO THE  EXEMPTION  CONTAINED  IN SECTION  4(2) OF THE
SECURITIES ACT OF 1933. THESE SECURITIES MAY NOT BE SOLD OR TRANSFERRED UNLESS A
REGISTRATION  STATEMENT  HAS BECOME AND IS THEN  EFFECTIVE  WITH RESPECT TO SUCH
SECURITIES  OR BARRINGER  LABORATORIES,  INC. HAS RECEIVED AN OPINION OF COUNSEL
REASONABLY  SATISFACTORY TO IT, TO THE EFFECT THAT THE PROPOSED SALE OR TRANSFER
IS EXEMPT FROM  REGISTRATION  UNDER THE SECURITIES ACT OF 1933, AS AMENDED,  AND
ALL APPLICABLE STATE SECURITIES ACTS AND LAWS.


                                CONVERTIBLE NOTE
                                       OF
                          BARRINGER LABORATORIES, INC.

$____________________                                           October __, 1999


     BARRINGER LABORATORIES,  INC., a Delaware corporation (the "Company"),  for
value  received,  hereby promises to pay to the order of  ________________  (the
"Investor") or his permitted  assigns (in each case, the "Holder") at 15000 West
6th   Avenue,   Suite   300,   Golden,   Colorado   80401-5047,   the   sum   of
$___________________.  The  Company  shall  only  pay  interest  (to the  extent
permitted  by law) on any overdue  principal on this Note at the rate of 10% per
annum,  from the due date of such  principal  until  payment in full  thereof is
made.  The  principal  amount  then  outstanding  of this Note  shall be due and
payable in full on the 365th day from the date  hereof  (the  "Maturity  Date").
This Note is originally being issued pursuant to a Subscription Agreement, dated
October ___, 1999 (the "Original Issue Date"), between the Company, the Investor
and,   perhaps  others   (collectively,   the   "Investors")   (each  Investor's
Subscription  Agreement are collectively  referenced herein as the "Subscription
Agreement").  All Notes issued under the Subscription  Agreement are referred to
herein as the "Notes."

     The following is a statement of the rights of the Holder and the conditions
to which this Note is subject, and to which the Holder hereof, by the acceptance
of this Note, agrees:

<PAGE>




     1. Security.  The obligations  evidenced by, arising under or in connection
with,  this Note are  secured  by a security  interest,  created  pursuant  to a
certain  Security  Agreement,  dated  as  of  the  date  hereof  (the  "Security
Agreement"),  among the Company and the Investors, in the Collateral (as defined
in the Security Agreement).

     2.  Financing  Statements.  The  Company  shall  execute and deliver to the
Investor (i) the Security  Agreement;  (ii) Uniform  Commercial  Code  Financing
Statements (Form UCC-1) or appropriate  local equivalent in appropriate form for
filing under the Uniform Commercial Code or appropriate local equivalent of each
jurisdiction as may be necessary to perfect the security interests  purported to
be created by the Security  Agreement;  and (iii) all other documents  necessary
or, in the  reasonable  opinion  of the  Investor,  desirable,  to  perfect  the
security  interests  in the  Collateral  purported to be created by the Security
Agreement.

     3.  Amendments.  This Note may not be  amended,  modified  or waived in any
respect unless set forth in writing and signed by the Company and the Holder.

     4.  Notices.  So long as this Note remains  outstanding,  the Company shall
maintain an office or agency (which shall  initially be the  principal  place of
business of the Company  located at 15000 West 6th  Avenue,  Suite 300,  Golden,
Colorado  80401-5047)  where notices,  presentations  and demands to or upon the
Company  in respect  of this Note may be given.  All  notices to be given by the
Company to the Holder in  respect of this Note shall be  delivered  or mailed to
the  address of the Holder set forth on the records of the Company or such other
address as shall be designated in writing by the Holder to the Company.

     5. Events of  Default.  (a) The  following  shall  constitute  an "Event of
Default" under this Note:

               (i)  Default  shall be made in any  payment  of  principal  of or
          interest on this Note when the same shall become due and payable,  and
          such  principal or interest  shall remain unpaid for 30 days after the
          date upon which such payment was due;

               (ii) any  representation or warranty made by the Company under or
          in connection with the Subscription Agreement, the Security Agreement,
          the  Registration  Rights  Agreement,  dated  as of the  date  hereof,
          between  the  Company  and the  Investors  (the  "Registration  Rights
          Agreement,"  and  together  with the  Subscription  Agreement  and the
          Security Agreement, the "Transaction Documents"), or any certification
          or other  instrument  furnished  in  connection  with any  Transaction
          Document or the transactions contemplated thereby, shall prove to have
          been false or misleading in any material respect;

               (iii) default shall be made in the due  observance or performance
          of any covenant or agreement (other than as contemplated by clause (i)
          above)  to be  observed  or  performed  by the  Company  or any of its
          subsidiaries  for the  benefit  of the  Holder  under this Note or any
          Transaction  Document  and  such  default  shall  remain  uncured  and
          unwaived for a period of 30 days after written notice thereof is given
          to the Company by the Holder,  unless the Holder  determines  that the
          Company has  diligently  instituted  and is  continuing  diligently to
          pursue corrective action sufficient to cure such default;

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<PAGE>


               (iv) The Company shall (A) voluntarily commence any proceeding or
          file any petition  seeking  relief under Title 11 of the United States
          Code or any other Federal or state  bankruptcy,  insolvency or similar
          law,  (B) consent to the  institution  of any such  proceeding  or the
          filing  of  any  such  petition,  (C)  apply  for  or  consent  to the
          appointment of a receiver, trustee, custodian, sequestrator or similar
          official  for  the  Company  or  such  Subsidiary  or  for  all  or  a
          substantial  part of its properties,  (D) file an answer admitting the
          material  allegations  of a  petition  filed  against  it in any  such
          proceeding,   (E)  make  a  general  assignment  for  the  benefit  of
          creditors,  or (F) admit in writing its  inability to pay its debts as
          they become due;

               (v)  an   involuntary   proceeding   shall  be  commenced  or  an
          involuntary   petition   shall  be  filed  in  a  court  of  competent
          jurisdiction  seeking (A) relief in respect of the Company,  or of all
          or a substantial part of the properties thereof, under Title 11 of the
          United  States  Code  or  any  other  Federal  or  state   bankruptcy,
          insolvency or similar law, (B) the appointment of a receiver, trustee,
          custodian,  sequestrator or similar  official for the Company or for a
          substantial part of the properties  thereof,  or (C) the winding up or
          liquidation  of the  Company;  and an order  or  decree  approving  or
          ordering  any of the  foregoing  shall  be  issued  by a court  having
          jurisdiction and continue unstayed and in effect for 60 days; or

               (vi) an  unappealed  final  judgment  for the payment of money in
          excess of $250,000  shall be  rendered  against the Company or and the
          same  shall  remain  undischarged  or  unbonded  for  a  period  of 60
          consecutive days during which execution shall be effectively stayed.

          (b) In case of any Event of Default and at any time thereafter  during
the continuance of such Event of Default, the holders of a majority in principal
amount of the Notes then  outstanding  may,  by written  notice to the  Company,
declare  the  Notes  to be due and  payable  in full  both as to  principal  and
interest, together with a prepayment premium equal to 1% of the principal amount
of the Note as of the date thereof;  provided,  however,  that no notice need be
given to the  Company  if  acceleration  is based  upon the  Events  of  Default
described  in clauses  (v) or (vi) of  paragraph  (a) above,  in either of which
cases this Note shall automatically become due and payable without any action on
the part of the holders.

          (c) In case an Event of Default shall have occurred and be continuing,
the Holder  may  proceed to protect  and  enforce  its rights  either by suit in
equity or by action at law, whether for the specific performance of any covenant
or agreement  contained in the  Transaction  Documents or this Note or in aid of
the exercise of any power granted in the Transaction  Documents or in this Note,
or proceed to enforce  the payment of this Note or to enforce any other legal or
equitable right of the Holder.  No remedy conferred  hereunder is intended to be
exclusive of any other remedy and each such remedy shall be cumulative and shall
be in addition to every other remedy  given  hereunder or currently or hereafter
existing at law or in equity or by statute or otherwise.


     6.  Conversion.

          6.1 Election by Company.  The Company has the right, at any time until
the Maturity  Date,  to convert this Note in accordance  with the  provisions of
Subsection 6.2 hereof,  in whole or in part,  into fully paid and  nonassessable
shares of the Common  Stock,  par value  [$0.01] per share,  of the Company (the
"Common  Stock").  The number of shares of Common Stock into which this Note may


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<PAGE>


be  converted  at any given  time shall be  determined  by  dividing  the unpaid
principal amount by the Conversion  Price. As used herein,  the term "Conversion
Price" shall mean a price of $0.06 per share, subject to adjustment as set forth
in Section 8.

          6.2  Conversion  Procedure.  The Company  anticipates  that will be in
position to take all action as is  necessary  to  increase  the  authorized  but
unissued  shares of its common  stock  during the first  quarter of fiscal  year
2000, if not sooner.  Therefore,  if not sooner than or during the first quarter
of fiscal  year 2000,  the Company  shall,  as soon as  reasonably  practicable,
convert this Note into shares of Common Stock and shall issue and deliver to the
Holder a certificate  or  certificates  for the number of Shares so converted to
which the Holder is entitled in accordance  with the terms and conditions of the
Subscription  Agreement.  Such  conversion  shall be  deemed  to have  been made
immediately prior to the close of business on the date that the Company issues a
certificate or certificates  representing  such Shares and the person or persons
entitled to receive the Shares  shall be treated for all  purposes as the record
holder or  holders of such  Shares as of such  date.  On such date that the full
outstanding  principal  balance  of this Note is  converted  to Common  Stock as
provided herein, this Note shall be deemed to be paid in full. On such date, the
Holder shall take reasonable action to surrender this Note to the Company and to
reflect that it has been paid in full.

          6.3 No Fractional  Shares.  No fractional shares of Common Stock shall
be issued  upon  conversion  of this Note.  In lieu of the  Company  issuing any
fractional  shares to the Holder upon the  conversion of this Note,  the Company
shall pay to the Holder in immediately available funds the amount of outstanding
principal  that is not so converted.  Upon  conversion in whole of this Note and
the proper issuance of a certificate or certificates representing the Shares and
payment in lieu of fractional shares, the Company shall be forever released from
all its obligations and liabilities under this Note.

     7. Reservation of Common Stock. If not sooner, than during as or reasonably
practicable  after the first quarter of fiscal year 2000, the Company shall take
all action as is  necessary to increase  the amount of  authorized  but unissued
shares of Common Stock. Thereafter,  the Company shall at all times duly reserve
a sufficient  number of shares of  authorized  Common  Stock for  issuance  upon
conversion of all Notes.  Upon  issuance,  sale and delivery of a certificate or
certificates  representing  the Shares,  such Shares shall be validly issued and
outstanding,  fully paid and nonassessable with no personal liability  attaching
to the ownership thereof,  and shall not be subject to preemptive or any similar
rights of any person or entity.

     8. Adjustment of Conversion  Price.  (a) If, at any time after the Original
Issue Date, the number of outstanding shares of Common Stock is (i) increased by
a stock  dividend  payable  in  shares of Common  Stock or by a  subdivision  or
split-up  of shares of Common  Stock,  or (ii)  decreased  by a  combination  or
reverse split of shares of Common Stock,  then,  following the record date fixed
for the  determination  of  holders of Common  Stock  entitled  to  receive  the
benefits of such stock dividend,  subdivision,  split-up, combination or reverse
split,  the  Conversion  Price shall be  adjusted  to a new amount  equal to the
product of (A) the  Conversion  Price in effect on such  record date and (B) the
quotient  obtained  by  dividing  (x) the  number  of  shares  of  Common  Stock
outstanding on such record date (without  giving effect to the event referred to
in the foregoing clause (i) or (ii)) by (y) the number of shares of Common Stock
which  would be  outstanding  immediately  after  the event  referred  to in the
foregoing clause (i) or (ii), if such event had occurred  immediately  following
such record date.


                                       4
<PAGE>


          (b) If, at any time after the Original  Issue Date,  the Company shall
issue or be deemed to have issued (as  provided  below)  shares of Common  Stock
without  consideration or for a consideration per share less than the Conversion
Price in effect immediately prior to such issuance or deemed issuance, then such
Conversion  Price shall be lowered to a price equal to the quotient  obtained by
dividing  (i) an amount equal to the sum of (A) the product of (x) the number of
shares of Common Stock outstanding  immediately prior to such issuance or deemed
issuance  and  (y) the  then  existing  Conversion  Price,  and  (B)  the  total
consideration  received or deemed  received by the Company upon such issuance or
deemed issuance,  by (ii) the total number of shares of Common Stock outstanding
immediately  after such  issuance or deemed  issuance.  For the  purposes of any
adjustment of the  Conversion  Price pursuant to this  paragraph,  the following
provisions shall be applicable:

               (i) In the case of the  issuance  of Common  Stock for cash,  the
          consideration  shall be deemed to be the amount of cash paid  therefor
          without  deducting  therefrom  any  discounts,  commissions  or  other
          expenses allowed, paid or incurred by the Company for any underwriting
          or otherwise in connection with such issuance.

               (ii)  In  the  case  of  the  issuance  of  Common  Stock  for no
          consideration, the consideration shall be deemed to be $.01 per share.

               (iii)  In  the  case  of  the  issuance  of  Common  Stock  for a
          consideration  in whole or in part other than cash, the  consideration
          other than cash shall be deemed to be the fair market value thereof as
          determined  in good faith by the Board of Directors,  irrespective  of
          any accounting treatment.

               (iv) In the case of the issuance of options to purchase or rights
          to subscribe for Common Stock,  securities by their terms  convertible
          into or  exchangeable  for Common  Stock,  or options to  purchase  or
          rights to subscribe for such convertible or exchangeable securities:

                    (A) The shares of Common Stock  deliverable upon exercise of
               such options to purchase or rights to subscribe  for Common Stock
               shall be deemed to have been  issued at the time such  options or
               rights  were  issued  and  for  a  consideration   equal  to  the
               consideration  (determined in the manner  provided in clauses (i)
               through  (iii) above),  if any,  received by the Company upon the
               issuance  of such  options or rights  plus the  minimum  purchase
               price  provided  in such  options or rights for the Common  Stock
               covered thereby.

                    (B) The shares of Common Stock  deliverable  upon conversion
               of or in  exchange  for  any  such  convertible  or  exchangeable
               securities  or upon the exercise of options to purchase or rights
               to subscribe for such convertible or exchangeable  securities and
               subsequent  conversions  or exchanges  thereof shall be deemed to
               have been issued at the time such  securities were issued or such
               options or rights  were issued and for a  consideration  equal to
               the consideration received by the Company for any such securities
               and related  options or rights  (excluding  any cash  received on
               account  of accrued  interest  or  accrued  dividends),  plus the
               additional  consideration,  if any, to be received by the Company
               upon  the  conversion  or  exchange  of  such  securities  or the
               exercise of any related options or rights (the  consideration  in
               each case to be determined in the manner  provided in the clauses
               (i) through (iii) above).


                                        5


<PAGE>


                    (C) Upon any  change  in the  exercise  price of  shares  of
               Common  Stock  deliverable  upon  exercise of any such options or
               rights or  conversion  of or  exchange  for such  convertible  or
               exchangeable  securities,  other than a change resulting from the
               antidilution  provisions  thereof,  the Conversion Price shall be
               readjusted  to such  Conversion  Price as would have obtained had
               the adjustment made upon the issuance of such options,  rights or
               securities not converted  prior to such change been made upon the
               basis of such change.

                    (D) Upon  expiration  of any such  options  or  rights,  the
               termination  of any such  rights to convert or  exchange,  or the
               expiration of any options or rights  related to such  convertible
               or  exchangeable  securities,   the  Conversion  Price  shall  be
               readjusted  to such  Conversion  Price as would have obtained had
               such options, rights,  securities or options or rights related to
               such securities not been issued.

                    (E) No further  adjustments of the Conversion Price shall be
               made upon the actual  issuance  of such  Common  Stock or of such
               convertible  or  exchangeable  securities  upon  exercise of such
               options or rights,  or upon the actual  issuance  of such  Common
               Stock  upon  conversion  or  exchange  of  such   convertible  or
               exchangeable securities.

          (c) All  calculations  under this Section shall be made to the nearest
cent ($.01).

          (d) Whenever the Conversion Price shall be adjusted as provided above,
the Company shall deliver to the Holder a statement,  signed by its President or
Chief Financial  Officer,  showing in detail the facts requiring such adjustment
and the Conversion Price that shall be in effect after the adjustment.

     9. Adjustment of Shares. Following any Corporate Reorganization (as defined
below) after the Original Issue Date,  this Note shall be  convertible  into the
kind and number of shares of capital stock or other securities or property which
the Holder would have owned or have been entitled to receive with respect to the
Shares  had  this  Note  been  converted  immediately  prior  to such  Corporate
Reorganization.  The foregoing  provision  shall  similarly  apply to successive
Corporate  Reorganizations.  "Corporate  Reorganization"  means (i) any  capital
reorganization or  reclassification  of the capital stock of the Company,  other
than (A) a change in par value or from par  value to no par  value,  or (B) as a
result of a stock dividend or subdivision,  split-up,  or combination of shares,
and (ii) any  merger  or  consolidation  of the  Company  pursuant  to which the
stockholders of the Company are to receive cash, securities, or other properties
in exchange for the shares of capital stock of the Company then held by them.

     10.  Extension of Maturity.  Should the principal of or premium or interest
on this Note become due and payable on other than a business  day,  the maturity
thereof shall be extended to the next succeeding business day, and, with respect
to the interest on the principal,  interest shall be payable thereon at the rate
per annum herein specified during such extension.  The term "business day" shall
mean any day that is not a  Saturday,  Sunday or legal  holiday  in the State of
Delaware.

     11. Costs and Expenses.  The Company agrees to pay all reasonable costs and
expenses,  including  reasonable  attorneys'  fees,  incurred  by the  Holder in
collecting or enforcing this Note.

                                       6
<PAGE>


     12. No  Waivers.  No delay by the Holder in  exercising  any power or right
hereunder shall operate as a waiver of any power or right,  nor shall any single
or partial  exercise of any power or right  preclude  other or further  exercise
thereof, or the exercise of any other power or right hereunder or otherwise.

     13.  Transfer of Note.  Subject to the  restrictions  on transfer set forth
herein and in the Subscription Agreement, this Note and all rights hereunder are
transferable  in whole or in part.  Any transfer shall be effected by the Holder
in person or by duly  authorized  attorney by surrendering  this Note,  properly
endorsed,  at the office of the Company.  Each taker and holder of this Note, by
taking or holding the same,  consents  and agrees that this Note shall be deemed
negotiable, and, when appropriately endorsed the holder hereof may be treated by
the Company and all other persons  dealing with this Note as the absolute  owner
hereof  for any  purposes  and as the person  entitled  to  exercise  the rights
represented by this Note, or to the transfer hereof on the books of the Company,
any notice to the  contrary  notwithstanding;  but until such  transfer  on such
books,  the Company may treat the  registered  holder hereof as the owner hereof
for all purposes, any notice to the contrary notwithstanding.

     14.  Governing  Law.  This Note  shall be  governed  by and  construed  and
enforced  in  accordance  with  the  laws of the  State  of  Colorado.  Whenever
possible,  each provision of this Note shall be interpreted in such manner as to
be effective and valid under  applicable  law, but if any provision of this Note
shall be prohibited by or invalid under  applicable law, such provision shall be
ineffective  only to the  extent  of such  prohibition  or  invalidity,  without
invalidating the remainder of such provision or the remaining provisions of this
Note.

     15. Notices. All notices,  demands or other communications  hereunder shall
be in writing and shall be deemed  given when  delivered  personally,  mailed by
certified mail, return receipt requested,  sent by overnight courier service, or
telecopied  (transmission  confirmed  and a  copy  sent  by  personal  delivery,
certified mail or overnight courier service) to the following  addresses or such
other address as may be designated in writing by either party in accordance with
the terms of this provision:

          Holder:
                         ------------------------
                         ------------------------
                         ------------------------
                         ------------------------
                         Telecopier:
                                    -------------




          The Company:   Barringer Laboratories, Inc.
                         15000 West 6th Avenue
                         Suite 300
                         Golden, Colorado 80401-5047
                         Telecopier: (303) 277-1689




                                       7

<PAGE>


     IN WITNESS  WHEREOF,  the Company has caused  this  Convertible  Note to be
issued as of the date first set forth hereinabove.

                                             BARRINGER LABORATORIES, INC.



                                             By:
                                                --------------------------------
                                                Name:
                                                Title:


















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