X0202 4 2005-09-20 0000804212 AIRGAS INC ARG 0000908893 MCCAUSLAND PETER C/O AIRGAS, INC. 259 N. RADNOR-CHESTER ROAD, SUITE 100 RADNOR PA 19087 1 1 1 0 Chairman of the Board and CEO 0001083687 MCCAUSLAND BONNIE F C/O AIRGAS, INC. 259 N. RADNOR-CHESTER ROAD, SUITE 100 RADNOR PA 19087 0 0 1 0 Common Stock 2005-09-20 4 S 0 1000000 27.50 D 7254466 D Common Stock 1500 I Immediate Family Common Stock 41819 I 401(k) Plan Common Stock 2005-04-20 4 J 0 307340 D 0 I Trust F/B/O Children Includes 15,700 shares owned directly by Peter McCausland and indirectly by Bonnie F. McCausland. Represents 1,500 shares owned directly by Bonnie F. McCausland and indirectly by Peter McCausland. The information presented is as of 9/13/2005, the date of the latest available statement of Peter McCausland's holdings of Airgas, Inc. common stock in his 401(k) plan. Since 4/8/2005, the date relied upon for the amount reported on Peter McCausland's May 18, 2005 Form 4, a total of 115 shares have been acquired in transactions exempt from Section 16(b) by Rule 16b-3(c). These shares of Airgas, Inc. common stock are held in trust for the benefit of the Reporting Persons' children, under which each child is a beneficiary of the trust. On or about April 20, 2005, Bonnie McCausland resigned as a trustee of the trust (and, as a result, as of and since such time, neither of the Reporting Persons has been a trustee of the trust), thereby eliminating each Reporting Person's power to vote, dispose of or direct the voting or 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. Not applicable. Dean A. Bertolino, Attorney-in-Fact for Peter McCausland 2005-09-22 Dean A. Bertolino, Attorney-in-Fact for Bonnie F. McCausland 2005-09-22