What does the term "filter efficiency" mean?

The term "filter efficiency" specifically refers to the effectiveness of a filter in preventing particulates from passing through it. This is measured by how well the filter can capture and hold particles of various sizes. In practical applications, such as in air or water filtration systems, a high filter efficiency means that fewer contaminants are allowed to penetrate through the filter material. This is critical for ensuring cleaner air, water, or other materials the filter is designed to protect.

Understanding filter efficiency is essential, especially in contexts like pesticide application, where minimizing the escape of harmful substances into the environment is crucial. Filters with high efficiency are capable of trapping more particulates, thus providing better protection and maintaining safety standards.

The other choices do not accurately capture the essence of what filter efficiency represents. For instance, the effectiveness of a filter to prevent airflow relates more to its overall design and operational characteristics rather than its efficiency in capturing particulates. Similarly, the ability of a filter to resist degradation over time pertains to its durability, not its efficiency in filtering. Lastly, the total weight of filter material is not a measure of how effective a filter is at serving its purpose, as it does not directly correlate to the filter's ability to capture particles.