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EXHIBIT 21.1
Jurisdiction and
Name of Subsidiary Date of Incorporation
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Centrifugal Associates, Inc. New Jersey, 10/20/64
Mechanical Associates, Inc. New York, 3/31/89
Centrifugal Service, Inc. New York, 9/4/92
The Automation Group, Inc. Delaware, 5/25/95
Trident Mechanical Systems, Inc. Delaware, 5/25/95
Centrifugal/Mechanical Associates, Inc. Delaware, 6/9/95
Property Control, Inc. Delaware, 6/9/95
High-Rise Electric, Inc. Delaware, 7/5/95
Grace Systems Technologies, Inc. Delaware, 2/2/96
DualStar Communications, Inc. Delaware, 2/2/96
Integrated Controls Enterprises, Inc. Delaware, 8/30/96
HR Electrical Systems, Inc. Delaware, 6/10/98
ParaComm, Inc. Delaware, 6/23/99
BMS Electric, Inc. New York, 7/27/00
