Bosch Air Filter FAQs

Bosch filtration take time out to answer some frequently asked questions about air filters.

1. What does the initial restriction test show?

This test ensures the airflow at the intake is not slowed too much by a new air filter.

2. Why is the dust retention capacity so important and how is it measured?

This quality feature decides upon the filter service life. It indicates the amount of dirt the filter is able to collect before having to be replaced. At the same time, compliance with the specified differential pressure is to be ensured. Bosch measures this by means of ISO 5011 simulation tests.

3. How important is the filter surface and how does Bosch compare to others in this regard?

The filter surface is an important criterion for optimum filter performance, but it's not the only one. A perfectly matched combination and coordination of several different components of the filter medium – that is, e.g. pleats, grammage (thickness) and surface finish (embossing, coating) – are decisive factors. In this regard, Bosch applies the same standards for functional and quality tests as for original equipment.

4. How is the filter medium connected to the filter frame?

A lasting and robust connection between filter medium and filter frame is of major importance in order to prevent any bypass of unfiltered – or unmetered – air into the engine. For this purpose and depending on the individual specifications, gluing or welding procedures are performed. Nonetheless, the procedure used has no influence on the quality of the connection.