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The EN1822 standard

In some situations the requirements on air quality are extremely high. Here you can think of surgery rooms, clean rooms, and lab facilities. If you want to be absolutely sure that dust particles, aerosols and germs are averted you should choose an absolute filter of TOPS.

EN1822:2010 standard

In January 2011, the NEN published a 5-part standard NEN EN1822 High Efficiency Air Filters (EPA, HEPA and ULPA). It describes the testing of filtration attributes for absolute filters in the filter production company, which are Efficient Particulate Air filter (EPA), High Efficiency Particulate Air filter (HEPA) and Ultra Low Penetration Air filter (ULPA). The standard does not apply to the in-situation testing of absolute filters in the build in state. For this the NEN EN ISO 14644-3 still applies.

TOPS Luchtfilters only delivers products that meet the european standard. Contact us for more information or a non-binding quote.

Standard EN1822:2010 consists of 5 parts:

  • Part 1: Classification, performance testing, marking
  • Part 2: Aerosol production, measuring equipment, particle counting statistics
  • Part 3: Testing flat sheet filter media
  • Part 4: Determining leakage of filter elements (scan method)
  • Part 5: Determining the efficiency of filter elements CEN/TC 195 ‘Air Filter for General Ventilation’ elaborated this revision and additions to EN 1822.

It replaces the previous version from 1998 (part 1 until part 3) and 2000 (part 4 and 5).

For The Netherlands the NEN commission 35107400002 ‘Begeleiding CEN TC 195’ cooperated with a team of experts on the new standard.

What has changed?

Part 1 shows a change resulting from the classification of filters H10 till H12; this is changed to E10 till E12. The class boundaries remain the same. This change in EPA-filter means that this group of filters is purely classified by its integral efficiency (efficiency of the entire filter surface). A leakage test for the purpose of classification is not wanted and not possible. Instead of an individual efficiency measurement chapter 7.4.4 (and part 5 chapter 4.4) show that it is possible to determine the efficiency based on statistical values. For types H and U the individual efficiency measurement en leakage test are not changed.

Table: Classification of EPA, HEPA and ULPA filters

Changes in part 4

Parts 2 and 3 have not been changed. Part 4 describes the alternative method to achieve a leakage test (scanning method) with a solid testing fluid, polystyrene latex (PSL) in the informative Annex D. This is mainly important for the field of micro-electronics, where the use of an oily test aerosol is mostly not wanted or even expelled because of evaporation. The efficiency determination and classification should, however, be conducted with an oily test aerosol, as described in part 1. In practice, when there is a hard requirement for a solid test aerosol , only a scanning test will be done and the efficiency determination and classification (with statistical proof) will only be applied to separate filters.

In the informative Annex E an alternative method is described to test H13 filters using a particle accelerator in the range 0.3-0.5 m. Based on experience and a theoretical calculation of a predefined leakage an H13-filter with a local value of 99.75% should have an efficiency of 99.9996% in the reach of 0.3-0.5 m. This method can be used to meet any objection against the already existing in Annex A described visual oil leakage test. Besides this, the method can be used for H13 filters with filter packages in round shapes or V-shapes.

Besides the current detailed description (for absolute filtered made of micro fiberglass) of the efficiency measurement in the MPPS (Most Penetrating Particle Size) Part 5 in chapter 4.4 gives an elaborate description of the statistical method to determine the efficiency of EPA filters.

In the introduction it already becomes clear that for membrane filters and filters with loaded synthetical medium different rules apply. A membrane medium are more and more applied in the field of micro-electronics where the use of micro fiber glass in different processes leads to the unwanted deposit of Boron. Every membrane media has a MPPS of 0.1m. PTFE membrane media have an MPPS of 0.07m (70 nanometers).

Informative Annex A

The informative Annex A provides 2 methods to test absolute filters using membrane media. Despite the lower limit for detection of 0.05 m, a direct MPPS-determination can only occur with a CNC (Condensed Nucleus Counter). For the alternative use of a laser particle counter and a 0.14 m DEHS aerosol the Annex provides a calculation and reporting example. The normative Annex B discusses the efficiency calculation and classification of absolute filters, produced with an electrostatic charged synthetic medium. Synthetic media with nominal efficiency rates of 99.95% have lately been available in bigger quantities. High efficiency rates are obtained by twisting finer fibers and to charge the fibers electrostatical.

Discharge procedure in the standard

These synthetic media are proposed as an alternative for absolute filters made of micro fiber glass. The “constant” electrostatic charge disappears in time however because of neutralization of separated dust particles, especially when these aerosols are submicronparts of charged particles. For EPA-, HEPA- and ULPA- filters, that are selected based on a guaranteed starting efficiency rate and must maintain this rate over many years in crucial fields like healthcare, pharmacy and industry, this has been the reason to take this into account when the efficiency rate is determined. For mixtures from 20% synthetic fibers until the absolute filter paper these Annex B is a normative obligation.

For the discharge procedure the standard points out to EN779:2002 Annex A. The filter needs to be accommodated with a mentioning of the percentage charged synthetical fibers and efficiency rates and classification in discharged condition, according to the mentioned example. ‘Efficiency 99.98% for MPPS in discharged condition as per Annex B of EN 1822-5:2010’, ‘Filter class H13 as per EN 1822-1 and Annex B, EN1822-5:2010.’

Optionally can be added: ‘Efficiency 99.998% for MPPS in new, charged condition as per Annex B of EN 1822- 5:2010.

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