Global Processing

EPA approves transient partial flow sampling system as alternative to CVS systems

August 23, 2005

EPA has approved Sierra Instruments, Inc. and Caterpillar, Inc. to use the Model BG-3 Transient Partial Flow Sampling System (TPFSS) as an alternate procedure in lieu of the full-flow Constant Volume Systems (CVS). After 30 years of using bulky, expensive, and maintenance-prone full-flow CVS systems to demonstrate engine compliance to exhaust particulate emissions regulations, engine manufacturers now have a more cost-effective and efficient tool to develop and certify cleaner engines. Caterpillar will save millions on a planned engine test cell expansions by standardizing on the Sierra BG-3 for both engine R&D and certification. Compared to CVS systems, the Sierra BG-3 is about 10 percent of the cost, is more reliable and versatile for engine developers, yields more meaningful engine emissions data, requires minimal maintenance, and is portable.