Press Release Details

FOR IMMEDIATE RELEASE:
Thursday, December 15, 2005

FOR FURTHER INFORMATION:
Rich Sheffer (952) 887-3753


IVYLAND, PA – Dec. 15, 2005 – Donaldson Company, Inc. (NYSE:DCI) today announced that its plant in Ivyland, Pennsylvania had received its ISO 9001:2000 Certification.

The plant, a 60,000 square foot facility in the Philadelphia metropolitan area, produces Donaldson's expanded PTFE membranes and related composite materials which are marketed under the Tetratex® brand. These products include adhesive laminated fabrics used in high performance garments for firefighting, medical, military, and work wear; thermobonded composites used in industrial filtration applications, including coated filter bags and cartridge media; and other advanced PTFE membrane materials used in technical applications, including liquid microfiltration, venting, and medical applications.
 
"The achievement of this certification further demonstrates our commitment to provide the highest quality products, service and manufacturing capabilities to our customers," said Warren Hayslip, General Manager of Donaldson's Membranes business. "I am extremely proud of all of the individuals – production, administrative and management – who worked very hard over the past six months to secure this certification."

The International Organization of Standardization (ISO) is the source of the ISO 9000 and ISO 14000 families of quality and environmental management standards and approximately 14,000 international standards for business, government, and society. ISO is a network of national standards institutes from more than 140 countries working in partnership with international organizations, governments, industry, business, and consumer representatives.

Included among the ISO 9001:2000 standards are product defect tracking, supplier management, and corporate objectives and activities. Ongoing activities include employee and management training, the establishment of interrelated processes and systems to ensure that customer requirements are understood and met; ongoing quality goals and a detailed process for addressing and correcting problems.

About Donaldson Company
Donaldson is a leading worldwide provider of filtration systems and replacement parts. Donaldson is a technology-driven company committed to satisfying customer needs for filtration solutions through innovative research and development. Donaldson serves customers in the diesel engine and industrial markets including in-plant air cleaning, compressed air and gas purification, power generation, disk drive filtration, off-road equipment and trucks. Our 11,000 employees contribute to the company's success at over 30 manufacturing locations around the world. Donaldson is a member of the S&P MidCap 400 Index and Donaldson shares are traded on the NYSE under the symbol DCI. Additional company information is available at www.donaldson.com.

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