• Penn Ventilation Companies

• Pepcon Systems, a division of American Pacific Corp.

• Perfect Sense

• Permatron Corporation

• Phoenix Controls Corporation

• Photo Lab Systems, Inc.

• Plastinetics

• PlymoVent Corp.

• Pneuline Controls

• Pneumafil Corp.

• Polytron Filters

• Porta-Fab Corporation (Airo Clean)

• Pottorff Co.

• Powrmatic of Canada Ltd.

• Precision-Aire, Inc.

• Precisioneering Ltd.

• Pro Tech Associates

• Purafil, Inc.

• Purified Micro Enviroments

• Puroflow, Inc.

• Purolator Products Air Filtration Company

• Quality Filters

• QuickDraft Div.

• Rapid Engineering, Inc.

• Rapid Fan & Blower Inc.

• Raydot