NAFA Guide To Air Filtration

NAFA Guide To Air Filtration Chapter 8 HEPA and ULPA Filter Testing presented by the National Air Filtration Association Fifth Edition

HEPA Testing Challenge • Has to be non-destructive as each HEPA is individually tested • Should generate an aerosol whose size is MPPS • Monodispersed • Confirm particle size • Measure concentration upstream & downstream of filter

High Efficiency Filters HEPA Minimum Particle Collection Efficiency • 99.97% for 0.3 micron particles (Type A) Penetration Tested • 99.99% for 0.3 micron particles (Type C) Penetration and Leak Tested ULPA Minimum Particle Collection Efficiency • 99.999% For 0.10-0.20 Micron Particles (Type F) Penetration and Laser Tested See Page 8.5 for all HEPA Ratings and MOT

E x h a u s t A i r I n t a k e F i l t e r A i r F l o w H e a t e r s T e s t D O P R e s e r v o i r H o o d F i l t e r C o o l i n g C o i l s M o t o r / D O P B l o w e r V a p o r Efficiency testing Q 107 Hot DOP Penatrometer A l t e r n a t e E x h a u s t ( W h e n F i l t e r I s N o t B e i n g T e s t e d )

HEPA and ULPA Filter Testing A modern test device

HEPA Filter Testing • Penetration converted to overall efficiency including gaskets, sealing and framing • Initial resistance • Two-Flow Testing - leak test (scanning for leaks)

In-place Leak Testing • Done using “cold DOP” or other suitable challenge – it is poly-dispersed • Generator is placed upstream of HEPA filter to introduce challenge particles • Scanning with a photometer is done downstream to detect leaks

Media Damage from Shipping/Handling In-place scanning of HEPA

Mechanical Scan Device at Factory

Standards for HEPA Filters • UL 900 – Listed • UL 586 – involves exposing HEPA filter not only to aerosol penetration test, but heated air, moist air, cold air, flame, and others as required by user • IEST – has categorized filter testing for Type A through Type K

Standards for HEPA Filters • EN 1822 – is the European Standard for HEPA and ULPA filters and classifies them from H10-14 for HEPA and U15-17 for ULPA • Factory Mutual – 3rd party testing and verification company • ASME AG-1 (Nuclear applications) • Off-Gassing Qualifications

Not On Test But Good To Know Information Handling HEPA Filters • Limit Handling to Minimum • Use two people to move if >30” high or >36” wide • Do not drop, bump, stack or sit on filters • Do not allow filters to lay flat

Not On Test But Good To Know Information Removing HEPA Filter From Carton • Do not lift filter out of box! Open one end, turn box upside down, lift box off filter • Do not try to remove the filter by lifting it up from the box. You may puncture the media with your fingers • If a filter is equipped with a removal strap, you may carefully use this to remove the filter from the box • When handling, grasp the filter only on outside surface of frame

Storage of HEPA Filters • Store filter standing upright on edge so pleats are vertical, not lying flat. • Make sure filters are marked ‘Fragile” and stored in a ‘safe zone’ away from traffic or activity. • Filters <24” under high; stack 3 high. If filters are > 24” high or greater; stack only two high. • Do not expose to dampness, excessive heat or cold (120 degree F. max.), rapidly changing temperature or out of doors.

Summary - HEPA Filters • At least 99.97% Efficient on 0.3 micrometer challenge particles • Tested (scan and / or efficiency) using DOP or suitable substitute • Used to filter hazardous materials • Always changed with knowledge and PPE • Used in Bag In/Bag Out application • Should always be handled with care

Sample Questions • Minimum efficiency for filter to be a HEPA? 99.97% on 0.3 micrometer particles • European Standard for HEPA and ULPA filters is? EN1822 • Difference between Hot DOP and Cold DOP is? Size of particle challenge • Testing HEPA filters after installation is called? In-place Leak Testing or Cold DOP Test

Thank you. Other Questions ?

NAFA Guide To Air Filtration