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SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20059
SCHEDULE 13G
Under the Securities Exchange Act of 1934
(Amendment No. 4)
NAME OF ISSUER: Industrial Scientific Corporation
TITLE OF CLASS OF SECURITIES: Common Stock
CUSIP NUMBER: 45631G-10-6
Check the following box if a fee is being paid with this statement: [ ]
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CUSIP NO. 45631G-10-6
_________________________________________________________________
(1) Names of Reporting Persons Florence L. McElhattan Corporation
SS or IRS Identification Nos. SSN: ###-##-####
of Above Person
________________________________________________________________
(2) Check the Appropriate Box (See Instructions):
(a)________________________________
if a Member of a Group
(See Instructions)
(b)_______________X________________
Membership in any group is
disclaimed
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(3) SEC Use Only
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(4) Citizenship or Place United States of America
of Organization
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Number of Shares (5) Sole Voting Power 750,000
Beneficially
Owned by Each (6) Shared Voting Power 696,360*
Reporting Person with
(7) Sole Dispositive Power 750,000
(8) Shared Dispositive Power 696,360*
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(9) Aggregate Amount Beneficially Owned by Each
Reporting Person 1,446,360
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(10) Check if the Aggregate Amount in Row (9)
Excludes Certain Shares Not Applicable
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(11) Percent of Class Represented by Amount in Row 9 42.9
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(12) Type of Reporting Person
(See Instructions) IN
* See Exhibit A
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CUSIP NO. 45631G-10-6
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
(Under the Securities and Exchange Act of 1934)
Item 1(a) Name of Issuer:
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Industrial Scientific Corporation
Item 1(b) Address of Issuer's Principal Executive Offices:
------------------------------------------------
1001 Oakdale Road
Oakdale, PA 15071
Item 2(a) Name of Person Filing:
----------------------
Florence L. McElhattan
Item 2(b) Address of Principal Business Office:
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Industrial Scientific Corporation
1001 Oakdale Road
Oakdale, Pennsylvania 15071
Item 2(c) Citizenship:
------------
United States of America
Item 2(d) Title of Class of Securities:
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Common Stock, Par Value $.01 Per Share
Item 2(e) CUSIP Number:
-------------
45631G-10-6
Item 3 Statement filed pursuant to Rules 13d-1(b), or
13d-2(b).
Not Applicable.
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Item 4 Ownership:
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(a) Amount beneficially owned: 1,446,360*
(b) Percent of class: 42.9
* See Exhibit A
(c) Number of shares as to
which person has:
(i) Sole power to vote or
to direct the vote: 750,000
(ii) Shared power to vote
or to direct the vote: 696,360*
(iii) Sole power to dispose or
to direct the disposition
of shares: 750,000
(iv) Shared power to dispose or
to direct the disposition
of shares: 696,360*
Item 5 Ownership of Five Percent or Less of a Class:
---------------------------------------------
Not Applicable.
Item 6 Ownership of More than Five Percent on Behalf of Another Person:
----------------------------------------------------------------
Not Applicable.
Item 7 Identification and Classification of the Subsidiary Which
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Acquired the Security Being Reported by the Parent Holding
----------------------------------------------------------
Company:
--------
Not Applicable.
Item 8 Identification and Classification of Members of the Group:
----------------------------------------------------------
Not Applicable.
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Item 9 Notice of Dissolution of Group:
-------------------------------
Not Applicable.
Item 10 Certification:
--------------
Not Applicable.
* See Exhibit A
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SIGNATURE
After reasonable inquiry and to the best of my knowledge and belief, I certify
that the information set forth in this statement is true, complete and correct.
Date: February 13, 1998
/s/ Florence L. McElhattan
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Florence L. McElhattan
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Exhibit A
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* Includes 680,960 shares held directly by Kenton E. McElhattan, the husband
of the reporting person, and 14,400 shares held by a foundation that may be
deemed to be beneficially owned by Mr. McElhattan and therefore attributed
to the reporting person. Mrs. McElhattan disclaims beneficial ownership of
such shares.
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