Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
MCCAUSLAND PETER
   2. Issuer Name and Ticker or Trading Symbol
AIRGAS INC [ARG] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director __X__ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
Chairman of the Board and CEO
(Last)
(First)
(Middle)
C/O AIRGAS, INC., 259 N. RADNOR-CHESTER ROAD, SUITE 100		 3. Date of Earliest Transaction (Month/Day/Year)
05/16/2005
(Street)

RADNOR, PA 19087		 4. If Amendment, Date Original Filed(Month/Day/Year)
 6. Individual or Joint/Group Filing(Check Applicable Line)
___ Form filed by One Reporting Person
_X_ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)		 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)		 4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)		 5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)		 6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)		 7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock 05/16/2005   M   7,736 A $ 13.32 8,267,189 (1) D  
Common Stock 05/16/2005   M   64,264 A $ 13.32 235,340 (2) I Trust FBO Children
Common Stock 05/16/2005   M   72,000 A $ 17.31 307,340 (2) I Trust FBO Children
Common Stock 05/03/2005   J   374,356 (3) D (4) 1,500 (5) I Immediate Family
Common Stock               41,704 (6) I 401(k) Plan

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)		 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)		 5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)		 6. Date Exercisable and Expiration Date
(Month/Day/Year)		 7. Title and Amount of Underlying Securities
(Instr. 3 and 4)		 8. Price of Derivative Security
(Instr. 5)		 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)		 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)		 11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Stock Option (Right to Buy) $ 13.32 05/16/2005   M     7,736   (7) 05/22/2005 Common Stock 7,736 (4) 0 D  
Stock Option (Right to Buy) $ 13.32 05/16/2005   M     64,264   (7) 05/22/2005 Common Stock 64,264 (4) 0 I Trust FBO Children
Stock Option (Right to Buy) $ 17.31 05/16/2005   M     72,000   (7) 05/22/2005 Common Stock 72,000 (4) 0 I Trust FBO Children

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
MCCAUSLAND PETER
C/O AIRGAS, INC.
259 N. RADNOR-CHESTER ROAD, SUITE 100
RADNOR, PA 19087		   X   X   Chairman of the Board and CEO  
MCCAUSLAND BONNIE F
C/O AIRGAS, INC.
259 N. RADNOR-CHESTER ROAD, SUITE 100
RADNOR, PA 19087		     X    

Signatures

 Todd R. Craun, Attorney-in-Fact for Peter McCausland   05/18/2005
**Signature of Reporting Person Date
 Todd R. Craun, Attorney-in-Fact for Bonnie F. McCausland   05/18/2005
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Includes 15,700 shares owned directly by Peter McCausland and indirectly by Bonnie F. McCausland.
(2) Represents shares held in a trust for the benefit of the Reporting Persons' children.
(3) These shares of Arigas, Inc. common stock are held by the Reporting Persons' children in two separate trusts where each child is the settlor, beneficiary and a trustee of his or her respective trust. Neither of the Reporting Persons is a trustee of either trust. On May 3, 2005, each trust was amended to eliminate each child's power to vote, dispose of or direct the disposition of the shares held in trust. Each of the Reporting Persons disclaims beneficial ownership of these securities and this report shall not be deemed to be an admission that either of them is the beneficial owner of such securities.
(4) Not applicable.
(5) Includes 1,500 shares owned directly by Bonnie F. McCausland and indirectly by Peter McCausland.
(6) The information presented is as of 4/8/2005, the date of the latest available statement of the reporting person's holdings of Airgas, Inc. common stock in his 401(k) plan. Since 2/9/2005, the date relied upon for the amount reported on the reporting person's February 15, 2005 Form 4, a total of 512 shares have been acquired in transactions exempt from Section 16(b) by Rule 16b-3(c).
(7) These options are fully exercisable.

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