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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
Under the Securities Exchange Act of 1934
(Amendment No. 5)
Industrial Scientific Corporation
(Name of Issuer)
Common Stock
(Title of Class of Securities)
45631G-10-6
(CUSIP Number)
December 31, 1998
(Date of Event Which Require Filing of this Statement)
Check the appropriate box to designate the rule pursuant to which this Schedule
is filed.
[ ] Rule 13d-1(b) (Qualified Investor)
[ ] Rule 13d-1(c) (Passive Investor)
[ X ] Rule 13d-1(d) (Exempt Investor)
*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter the
disclosures provided in a prior cover page.
The information required in the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities Exchange Act of
1934 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).
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CUSIP NO. 45631G-10-6
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(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 684,360*
Reporting Person
With (7) Sole Dispositive Power 750,000
(8) Shared Dispositive 684,360*
Power
________________________________________________________________________________
(9) Aggregate Amount Beneficially Owned by Each
Reporting Person 1,434,360
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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 42.4
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(12) Type of Reporting Person IN
(See Instructions)
* 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:
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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:
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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: 1,434,360*
(b) Percent of class: 42.4
* 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: 684,360*
(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: 684,360*
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:
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Not Applicable.
Item 7 Identification and Classification of the Subsidiary Which
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Acquired the Security Being Reported by the Parent Holding
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Company:
--------
Not Applicable.
Item 8 Identification and Classification of Members of the Group:
----------------------------------------------------------
Not Applicable.
Item 9 Notice of Dissolution of Group:
-------------------------------
Not Applicable.
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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 16, 1999
/s/ Florence L. McElhattan
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Florence L. McElhattan
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EXHIBIT A
---------
* Includes 669,960 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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