Exhibit 21

Airgas, Inc. and Subsidiaries



|                                                                     |  |            
|-------------------------------------------------------------------- |  | -----------
|Corporation Name                                                     |  | Domicile   
|                                                                     | 
|Airgas, Inc.                                                         |  | DE         
|Airgas Canada, Inc.                                                  |  | Canada     
|Airgas Carbonic, Inc.                                                |  | DE         
|Airgas Data, LLC                                                     |  | DE         
|Airgas East, Inc.                                                    |  | DE         
|Airgas Great Lakes, Inc.                                             |  | DE         
|Airgas Intermountain, Inc.                                           |  | CO         
|Airgas Investments, Inc.                                             |  | DE         
|Airgas Merchant Gases, LLC                                           |  | DE         
|Airgas Merchant Holdings, Inc.                                       |  | DE         
|Airgas Mid America, Inc.                                             |  | DE         
|Airgas Mid South, Inc.                                               |  | DE         
|Airgas Nor Pac, Inc.                                                 |  | DE         
|Airgas North Central, Inc.                                           |  | DE         
|Airgas Northern California & Nevada, Inc.                            |  | DE         
|Airgas Refrigerants, Inc.                                            |  | DE         
|Airgas Retail Services, LLC                                          |  | DE         
|Airgas S.A. de C.V.                                                  |  | Mexico     
|Airgas Safety, Inc.                                                  |  | DE         
|Airgas Sakhalin Holdings, Inc.                                       |  | DE         
|Airgas Sakhalin, LLC                                                 |  | Russia     
|Airgas South, Inc.                                                   |  | DE         
|Airgas Southwest, Inc.                                               |  | DE         
|Airgas Specialty Gases, Inc.                                         |  | TX         
|Airgas Specialty Products, Inc.                                      |  | DE         
|Airgas West, Inc.                                                    |  | CA         
|Airgas West, S.A.de C.V.                                             |  | Mexico     
|A & N Europe B.V.                                                    |  | Netherlands
|A & N Management Limited                                             |  | England    
|Medical Gas Management, Inc.                                         |  | DE         
|Missouri River Holdings, Inc.                                        |  | KS         
|National Welders Supply Company, Inc. d.b.a. Airgas National Welders |  | NC         
|Nitrous Oxide Corp.                                                  |  | DE         
|Oilind Safety, Inc                                                   |  | DE         
|Radnor Funding Corp.                                                 |  | DE         
|Red-D-Arc, Inc.                                                      |  | NV         
|Red-D-Arc (Netherlands) B.V.                                         |  | Netherlands
|Red-D-Arc (FR) SAS                                                   |  | France     
|Red-D-Arc (U.K.) Limited                                             |  | UK         
|Red-D-Arc Limited                                                    |  | Canada     
|Red-D-Arc S.A.de C.V.                                                |  | Mexico     
|WorldWide Welding, LLC                                               |  | DE