HEPA Filter DOP Test

The HEPA filter DOP (Dispersed Oil Particulate) test is a type of test performed on High-Efficiency Particulate Air (HEPA) filters to determine their efficiency in filtering out particles. HEPA filters are designed to remove at least 99.97% of airborne particles that are 0.3 microns or larger in size, and the DOP test is used to confirm that they meet this standard.

During the DOP test, a challenge aerosol of a known concentration of dioctyl phthalate (DOP) particles is generated upstream of the filter. The filter is then scanned with a photometer downstream to measure the number of particles that penetrate through the filter. The penetration rate is calculated as the percentage of particles that pass through the filter compared to the total particles upstream.

The DOP test is considered to be one of the most rigorous tests for HEPA filters, and it is often used as part of the initial testing and ongoing maintenance of cleanrooms and other critical environments where high levels of air filtration are required. It is important to note that the DOP test is only one component of the overall testing and certification process for HEPA filters, which typically involves a range of physical, chemical, and microbiological tests to ensure their effectiveness in removing contaminants from the air.