X0303 4 2010-01-05 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 2008-12-18 5 G 0 9291 D 7174332 D Common Stock 2009-01-23 5 G 0 250000 D 6924332 D Common Stock 2009-02-02 5 G 0 6058 D 6918274 D Common Stock 2009-07-17 5 G 0 34508 A 6952782 D Common Stock 2009-08-17 5 G 0 718 D 6952064 D Common Stock 2009-12-11 5 G 0 15804 D 6936260 D Common Stock 2009-12-21 5 G 0 1000000 D 5936260 D Common Stock 2010-01-05 4 M 0 150000 5.50 A 6086260 D Common Stock 2010-01-05 4 M 0 150000 8.99 A 6236260 D Common Stock 1444210 I By trusts Common Stock 45772 I By 401(k) plan Common Stock 1500 I By immediate family Stock Option (Right to Buy) 5.50 2010-01-05 4 M 0 150000 D 2010-05-16 Common Stock 150000 0 D Stock Option (Right to Buy) 8.99 2010-01-05 4 M 0 150000 D 2011-05-08 Common Stock 150000 0 D Not applicable. Represents shares of Airgas, Inc. common stock transferred on 1/23/2009 to two separate grantor retained annuity trusts (each, a "GRAT") of which Peter McCausland is a co-trustee and either he or his spouse is a beneficiary. Represents shares of Airgas, Inc. common stock distributed to Peter McCausland and his spouse (and held jointly) from two separate GRATs of which Peter McCausland is a co-trustee with his spouse and either he or his spouse is a beneficiary. Represents shares of Airgas, Inc. common stock transferred on 8/17/2009 to two separate GRATs of which Peter McCausland is a co-trustee and either he or his spouse is a beneficiary. Represents shares of Airgas, Inc. common stock transferred on 12/11/2009 to two separate GRATs of which Peter McCausland is a co-trustee and either he or his spouse is a beneficiary. Represents shares of Airgas, Inc. common stock held in six separate GRATs of which Peter McCausland is a co-trustee and either he or his spouse is a beneficiary. The information presented is as of 1/7/2010, the date of the latest available statement of the reporting person's holdings of Airgas, Inc. common stock in his 401(k) plan. Since 12/11/2008, the date of the statement relied upon for the amount reported on the reporting person's Form 4 dated 12/15/2008, a total of 1,330 shares of common stock have been acquired in the reporting person's 401(k) plan through transactions exempt under Section 16(b). Represents shares of Airgas, Inc. common stock owned directly by his spouse and indirectly by Peter McCausland. These options became exercisable in 25% equal increments on each of 5/16/2001, 5/16/2002, 5/16/2003 and 5/16/2004. These options became exercisable in 25% equal increments on each of 5/8/2002, 5/8/2003, 5/8/2004 and 5/8/2005. Robert H. Young, Jr., Attorney-in-Fact for Peter McCausland 2010-01-07