St. Louis, MO., September 13, 2007 – St. Louis, Missouri-based Aerospace Filtration Systems, Inc. (AFS) is maintaining its strong commitment to safety and reliability in the Helicopter Emergency Medical Services (HEMS) industry with its growing line of helicopter engine Inlet Barrier Filter systems. AFS IBF users routinely experience improved power, margin and reduced engine wear, all of which equate to more effective air medical operations.

The company provides cutting-edge systems for several commercial helicopters, including popular air medical aircraft like the AgustaWestland A119 Koala, Eurocopter AS350 series, Bell 407, 206L-1(C30), 206L-3 and 206L-4.

David Brigham and his team at Texas-based United Rotorcraft have installed many AFS Inlet Barrier Filter systems on a variety of aircraft. Brigham says operators choose AFS for several reasons, including protection, performance and ease of maintenance.

“I’ve seen aircraft that may not have been meeting TBO before running with the IBF. Now these aircraft are always making it to TBO with the barrier filter installed,” says Brigham. AFS barrier filtration systems filter out more than 99 percent of dirt and sand, meaning significant reductions in engine damage when compared to traditional particle separators.

Brigham adds that the IBF’s bring reduced operating temperatures, meaning better aircraft performance and load-carrying capacity. “The extra margins on the power side are a huge benefit because EMS operators are operating on the performance edge already.”

AFS engineers focus on creating barrier filters that minimize installation impact. “The install is pretty straightforward and simple,” adds Brigham.

The company is introducing an IBF system for the popular Eurocopter EC130 single engine helicopter along with the MD Helicopters MD900 Explorer series, flown by several EMS units, and AFS officials hope for certifications later this year. AFS is also actively pursuing an engine filtration solution for Bell 430 operators facing frequent engine damage situations.

About AFS

AFS is the industry leader in the design, development and manufacture of high-performance engine IBF systems for commercial and military propulsion systems. AFS manufactures certified IBF solutions for the AgustaWestland A119 Koala, Bell 205A1, 206B, 407, 206L-3/4, 206L-1(C30), MD Helicopters MD 369 (MD 500H/D/E/F Series), and Eurocopter AS 350 B/BA/B1/B2/B3 (AS 350D/SD/SD2-Soloy STC). AFS is a wholly owned subsidiary of Donaldson Company, Inc. Traded on the NYSE under the symbol DCI, Donaldson is a member of the S&P MidCap 400 Index. Additional company information for AFS and DCI is available at www.afsfilters.com and www.donaldson.com.

Visit AFS at Booth 335 during the upcoming Air Medical Transport Conference/AMTC in Tampa, Fla., September 17-19, 2007.

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