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                                                                      EXHIBIT 21

                    Subsidiaries of BHA Group Holdings, Inc.


BHA Group, Inc., a Delaware corporation; PrecipTech, Ltd., a Canadian
corporation; BHA Group, Ltd., a Canadian corporation; BHA International, Inc., a
U.S. Virgin Islands corporation; BHA Group GmbH, a German corporation; BHA Group
International, Inc., a Delaware corporation; and BHA Technologies, Inc., a
Delaware corporation; BHA Purfilter S.L., a Spanish corporation; and BHA Group
International Holdings B.V., a Dutch corporation, are the only subsidiaries of
the Company, each of which are wholly-owned. Tool Rental and Supply Company,
Inc., a Delaware corporation; Midwest Precipitator Corporation, an Illinois
corporation (DBA Midwest Power Corporation); BHA Group AG, a Swiss corporation;
BHA Environmental Technology Company, Ltd., a China corporation; and BHA Group
Philippines, Inc., a Philippine corporation, are wholly-owned subsidiaries of
BHA Group, Inc. BHA Group International Pvt. Ltd., an India corporation, is a
wholly-owned subsidiary of BHA Group International, Inc.; BHA Technologies AG, a
Swiss corporation; and BHA Technologies K.K., a Japan corporation, are
wholly-owned subsidiaries of BHA Technologies, Inc.; BHA Group, C.A., a
Venezuelan corporation, is a wholly-owned subsidiary of BHA Purfilter S.L.; BHA
do Brazil Ltda, a Brazilian corporation; and BHA U.K. Ltd., a United Kingdom
corporation, are wholly-owned subsidiaries of BHA Group International Holdings
B.V.










