The difference between HEPA and ULPA filters

HEPA generally refers to high-efficiency air filters, which are mainly used to capture particulate dust and various suspended solids above 0.5μm. ULPA is called ultra-high-efficiency air filter, or ultra-low-penetration air filter. The filtering efficiency of 0.1~0.2μm particles, smoke and microorganisms and other dust particles can reach more than 99.999%.
Indoor air pollution can carry dust mites, mold spores and pollen, causing health problems for people with allergies or asthma. However, in commercial environments such as electronics manufacturing plants, air pollution can damage electrical equipment under development. High-efficiency air filters provide many benefits for maintaining a safe environment for personnel and preventing cross-contamination. High-efficiency particulate air (HEPA) and ultra-low particulate air (ULPA) filters are the most commonly used air filters in households, automobiles, biomedical manufacturing, pharmaceuticals, semiconductor manufacturing, clean rooms and hospitals that require very clean air. HEPA and ULPA. HEPA and ULPA used in commercial air filtration systems have many similarities, but they are different in many aspects.
Similarities:
HEPA and ULPA filters are both designed to trap small particulate pollutants in the airflow by forcing the air through a fine mesh. It is usually composed of glass fibers randomly arranged to form a dense mat, and the fiber diameter is between 0.5 and 2 microns. A combination of three main methods is used to capture particles. Diffusion, interception and inertial impact. And the ultimate similarity between the two filters is that they do not remove gas or odors. If you need to remove gas or orders from the environment, an activated carbon filter may be the ideal choice.
filter structure:
filtration process
1.**Standard particle filtration in the environment
2. Cannot remove gas and odor
3. Pre-filtration can increase the life and performance of the filter
  the difference:
As mentioned earlier, both filters are designed to remove very small particles, but how effective is each filter in removing the smallest contaminants?
HEPA filter should remove air particles with a diameter of 0.3μm, while ULPA filter should remove air with a diameter of 0.1μm. ULPA filters that are rated to remove 99.999% of air pollutants are considered more effective than HEPA filters. The efficiency rating of the HEPA filter is 99.995%.
HEPA efficiency grade: 99.995% removal of particles in the air, HEPA provides ISO5 level
ULPA efficiency grade: 99.999% removes particles in the air, ULPA provides ISO3 grade
filter application:
It is understood that HEPA and ULPA filters are essential to prevent the spread of airborne allergens, infections and cross-contamination in a series of commercial and residential environments. What else can HEPA/ULPA filters help protect? General laboratory equipment used in the semiconductor, pharmaceutical and biomedical industries requires filters to maintain a clean environment. This is a list of laboratory equipment that requires HEPA or ULPA filters.
1. Biological safety cabinet (BSC)
2. Laminar flow hood
3. Airtight glove box
4. Closed loop filter glove box
5. Pipeless exhaust hood