California verification for 13" diameter CRT filter
18 October 2012
The California Air Resources Board (ARB) has extended its verification of the Johnson Matthey CRT® Particulate Filter system to include 13" diameter systems for high horsepower 1994 to 2006 model year on-road engines up to 650 hp, such as those used in Class 7 and Class 8 trucks affected by the ARB’s Truck and Bus regulation.
“The essence of our 13" CRT filter design is that it is both cost effective and compact so it will fit on vehicles where competitor systems cannot due to their larger sizes,” said Marty Lassen, JM Director of Regulatory Affairs and Marketing. “The CRT filter is also the most trusted filter globally; it has been used for more than 200,000 retrofits.”
With this verification, the ARB has also approved the JM policies for filter swapping (filter cleaning flexibility) and re-designation (moving the CRT system from one vehicle to another).
The CRT Filter is a passively regenerating system that includes an oxidation catalyst that increases the NO2 concentrations, followed by a wall-flow particulate filter. The ARB verification requires that the applications must have an exhaust gas temperature greater than 240°C over 40% of the operating cycle, a NOx/PM ratio of at least 8, and that the engines must be certified to NOx or NOx+NMHC levels above 3.2 g/bhp-hr.
Source: Johnson Matthey | California ARB