<PAGE> 1
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
SCHEDULE 13G
Under the Securities Exchange Act of 1934
(Amendment No. 9)*
AIRGAS, INC.
______________________________________________
(Name of Issuer)
COMMON STOCK
_____________________________________________
(Title of Class of Securities)
009363 10 2
__________________________
(CUSIP Number)
December 31, 1999
_______________________________________________________
(Date of Event Which Requires Filing of this Statement)
Check the appropriate box to designate the rule pursuant to which
this Schedule is filed:
[ ] Rule 13d-1(b)
[ ] Rule 13d-1(c)
[ X ] Rule 13d-1(d)
*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).
(Continued on following page(s))
Page 1 of 5 pages
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CUSIP No. 009363 10 2 13G Page 2 of 5 pages
___________ __ __
___________________________________________________________________
1. NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Peter McCausland
___________________________________________________________________
2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [ ]
(b) [ X ]
___________________________________________________________________
3. SEC USE ONLY
___________________________________________________________________
4. CITIZENSHIP OR PLACE OF ORGANIZATION
United States
___________________________________________________________________
5. SOLE VOTING POWER
2,934,867
________________________________________________
NUMBER OF 6. SHARED VOTING POWER
SHARES
BENEFICIALLY 7,695,724
OWNED BY ________________________________________________
EACH 7. SOLE DISPOSITIVE POWER
REPORTING
PERSON 2,934,867
WITH ________________________________________________
8. SHARED DISPOSITIVE POWER
7,695,724
___________________________________________________________________
9. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
10,630,591
___________________________________________________________________
10. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
[ ]
___________________________________________________________________
11. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
14.5%
___________________________________________________________________
12. TYPE OF REPORTING PERSON*
IN
___________________________________________________________________
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CUSIP No. 009363 10 2 13G Page 3 of 5 pages
___________ __ __
___________________________________________________________________
Item 1(a) Name of Issuer
______________
Airgas, Inc.
Item 1(b) Address of Issuer's Principal Executive Offices
_______________________________________________
Airgas, Inc.
Radnor Court
259 North Radnor-Chester Road, Suite 100
Radnor, Pennsylvania 19087-5283
Item 2(a) Name of Person Filing
_____________________
Peter McCausland
Item 2(b) Address of Principal Business Office, or, if none, Residence
____________________________________________________________
Airgas, Inc.
Radnor Court
259 North Radnor-Chester Road, Suite 100
Radnor, Pennsylvania 19087-5283
Item 2(c) Citizenship
___________
United States
Item 2(d) Title of Class of Securities
____________________________
Common Stock, par value $.01 per share
Item 2(e) CUSIP Number
___________
009363 10 2
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CUSIP No. 009363 10 2 13G Page 4 of 5 pages
___________ __ __
___________________________________________________________________
Item 3 Not Applicable
Item 4 Ownership
_________
(a) and (b) Peter McCausland beneficially owned an aggregate
of 10,630,591 shares of the issuer's Common Stock, or approximately
14.5% of the shares outstanding, as of December 31, 1999, of which
1,258,633 shares were issuable upon exercise of employee stock options.
(c) Peter McCausland had sole power to vote or to direct
the vote, and sole power to dispose or to direct the disposition
of, 2,934,867 shares of the issuer's Common Stock, of which
885,369 shares were issuable upon exercise of employee stock
options. Mr. McCausland had shared power to vote or to direct
the vote, and/or shared power to dispose or to direct the
disposition of, 7,695,724 shares of the Common Stock, which
included 373,264 shares issuable upon exercise of employee stock
options and 27,663 shares held by a charitable foundation (the
"Foundation") of which Mr. McCausland is an officer and director.
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
_______________________________________________________________
No other person is known to have the right to receive or the
power to direct the receipt of dividends from, or the proceeds from the
sale of, the issuer's shares which are the subject of this Amendment to
Schedule 13G, except that, with respect to 7,668,061 shares, members of Mr.
McCausland's family share with Mr. McCausland the right, and, with respect
to 27,663 shares, the Foundation has the exclusive right, to receive
the dividends from and the proceeds of sale as to such shares.
Item 7 Identification and Classification of the Subsidiary Which Acquired
the Security Being Reported on By the Parent Holding Company
__________________________________________________________________
Not Applicable
Item 8 Identification and Classification of Members of the Group
_________________________________________________________
Not Applicable
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CUSIP No. 009363 10 2 13G Page 5 of 5 pages
___________ __ __
___________________________________________________________________
Item 9 Notice of Dissolution of Group
______________________________
Not Applicable
Item 10 Certification
_____________
Not Applicable
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.
February 8, 2000
__________________________________
Date
/S/Peter McCausland
__________________________________
Signature
Peter McCausland, Director,
Chairman of the Board, President
and Chief Executive Officer
__________________________________
Name/Title
