At Industrial Filter Corporation, we consistently manufacture HEPA Filters with efficiency greater than 99.97%. We have a complete test rig with the most modern equipments to test all parameters of HEPA filters and the media.

The following test equipments are available with us for testing:

  • 0.3 micron particle counter
  • Aerosol generator
  • Thickness gauge
  • Pressure drop gauge
  • Flow measurement anemometer

A Test Rig for the evaluation of standard 1700 SCMH HEPA Filters for their particulate removal efficiency and pressure drops has been put up.

The efficiency test method includes use of DOP Aerosol (Hetrodisperse) and Size Selective Particle Counter, which counts particles down to 0.3 microns. Each HEPA Filter manufactured by us is tested for its Initial Pressure Drop and Collection Efficiency at rated flow of 1700 CMH, as per our standard test procedure.

Results with regard to Air Flow, Pressure Drop and Collection Efficiency with Air Flow direction are pasted in a Test Certificate format on each HEPA Filter.

The following tests are carried out at our site on each and every filter manufactured as per MIL – STD – 282, Method 102.9 – 28/5/1956:-

  • Efficiency Test With Total Penetration
  • Pressure Drop Test
  • Flow Velocity Test

All HEPA filters are tested as MIL – STD – 282 which is one of the widely accepted industry standard for testing 0.3 micron efficiency and is required for compliance with most nuclear, military and U.L specifications.

We further carry out additional tests as

  • Core Tightness Test – As per BARC specs.
  • Rough Handling Test – As per MIL – STD – 282 Method 105.9 of 28/5/56

Additional Test for Category IIIn addition to above test category II classified HEPA filters are tested for:-

  • Hot air test at 370°C
  • Over pressure test at 250 mm wc
  • Flame test

Our unit is capable to consistently manufacture and supply HEPA filters of 99.97% efficiency down to 0.3 microns and more importantly, our test rig is approved by all the organizations as competent and reflecting the true efficiency of the filter.


Our lab facilities for evaluation of HEPA Media include

  • Efficiency and Pressure Drop Test as per MIL – STD – 282.
  • Basis Weight Measurement as per TAPPI Std T 410 os-68, revised 1968
  • Thickness Measurement as per BS : 3983 : Part 2 : 1982.
  • Water Repellency test as per MIL – STD – 282 Method 603.1 28/5/56.
  • Combustible Content as per BS : 3631 : 1984

We test filters using STANDARD TEST DUST.

WE have testing facilities as per IS 7613 and BS EN 779.

High efficiency upto 99% is obtained in PRE filters of 5/10/20 microns. An equally efficient PRE filter is important for the long life of HEPA filters. Many a times neglected, but the true life of a HEPA filter mainly depends on the conditioning and regular maintenance of PRE Filters.

Hence all PRE filters made at our site are meticulously tested and approved at only 99% efficiency.


Work environment gets contaminated due to gases, vapors, fumes, dust, mist, and smokes. Where control measures, such as, total enclosures, ventilation, remote control already provided on a process or operation, do not prevent contamination of work environment, or the danger to health is significant, use of respiratory protective equipment is recommended. While gases and vapors and removed by chemical reaction, absorption or adsorption, particulate matter is usually removed by simple mechanical filtration. Therefore it is desirable that the filter – type respirators are tested under simulated laboratory conditions and any defects are removed so the respirator affords desired protection at the time of actual use.

Each Respiratory Filter manufactured, like HEPA Filter is tested in a independent set up matching the requirements of IS : 9473 : 1980


To serve our customers we also render services for in-situ testing of HEPA FILTERS i.e.. VALIDATION.

Taking note of number of filters installed our scope of works includes :

  • Air Velocity Measurement through filters.
  • D. O. P Test of the filters, Total Penetration and Percentage Efficiency.
  • Classification of Room Area and Particle Count.
  • Laminar Flow Bench Test
  • Air Changes
  • PRE Filter Servicing.
  • Flow Pattern Test
  • Recovery Test