X0303 4 2008-12-11 0000804212 AIRGAS INC ARG 0000908893 MCCAUSLAND PETER C/O AIRGAS, INC. 259 N. RADNOR-CHESTER RD, STE. 100 RADNOR PA 19087 1 1 1 0 Chariman, President and CEO Common Stock 2008-05-08 5 G 0 22000 A 7020518 D Common Stock 2008-06-17 5 G 0 5678 D 7014840 D Common Stock 2008-06-18 5 G 0 1217 D 7013623 D Common Stock 2008-12-11 4 M 0 130000 11.50 A 7143623 D Common Stock 228000 I By trusts Common Stock 41500 I By immediate family Common Stock 44442 I By 401(k) plan Stock Option (Right to Buy) 11.50 2008-12-11 4 M 0 130000 D 2009-05-18 Common Stock 130000 0 D Represents 22,000 shares of Airgas, Inc. common stock distributed to Peter McCausland and his spouse (and held jointly) from two separate grantor retained annuity trusts (each, a "GRAT") of which Peter McCausland is a co-trustee with his spouse and either he or his spouse is a beneficiary. Not applicable. Includes 15,700 shares of Airgas, Inc. common stock owned directly by Peter McCausland and indirectly by his spouse. Represents 228,000 shares of Airgas, Inc. common stock held in two separate GRATs of which Peter McCausland is a co-trustee and either he or his spouse is a beneficiary. Represents 41,500 shares of Airgas, Inc. common stock owned directly by his spouse and indirectly by Peter McCausland. The information presented is as of 12/11/2008, the date of the latest available statement of the reporting person's holdings of Airgas, Inc. common stock in his 401(k) plan. Since March 7, 2008, the date of the statement relied upon for the amount reported on the reporting person's Form 4 dated March 11, 2008, a total of 735 shares of common stock have been acquired in the reporting person's 401(k) plan through transactions exempt under Section 16(b). These options became exercisable in 25% equal increments on each of 5/18/2000, 5/18/2001, 5/18/2002 and 5/18/2003. Robert H. Young, Jr., Attorney-in-Fact for Peter McCausland 2008-12-15