09/30200844 DC : 0

Foreword
Introduction
1 Scope
2 Normative references
3 Terms and definitions
4 Symbols and abbreviated terms
5 Requirements
6 Classification
7 Test rig and equipment
   7.1 Test conditions
   7.2 Test rig
   7.3 Aerosol generation
        7.3.1 DEHS Test Aerosol
        7.3.2 Neutralisation (conditioning) of aerosol
   7.4 Aerosol sampling system
   7.5 Flow measurement
   7.6 Particle counter
   7.7 Differential pressure measuring equipment
   7.8 Dust feeder
8 Qualification of test rig and apparatus
   8.1 Air velocity uniformity in the test duct
   8.2 Aerosol uniformity in the test duct
   8.3 Particle counter sizing accuracy
   8.4 Particle counter zero test
   8.5 Particle counter overload test
   8.6 100% efficiency test
   8.7 Zero% efficiency test
   8.8 Aerosol generator response time
   8.9 Pressure equipment calibration
   8.10 Pressure drop checking
   8.11 Dust feeder air flow rate
   8.12 Neutraliser
   8.13 Summary of qualification requirements
   8.14 Apparatus maintenance
9 Test materials
   9.1 Test air - cleanliness, temperature and
        humidity
   9.2 Test aerosol
   9.3 Loading dust
   9.4 Final filter
10 Test procedure
   10.1 Preparation of filter to be tested
   10.2 Initial pressure drop
   10.3 Initial efficiency
        10.3.1 Efficiency of discharged filter media
        10.3.2 Efficiency measurement
   10.4 Dust loading
        10.4.1 Dust loading procedure
        10.4.2 Arrestance
        10.4.3 Efficiency
        10.4.4 Average efficiency
        10.4.5 Dust holding capacity
11 Uncertainty calculation of the test results
12 Reporting
   12.1 General
   12.2 Summary
   12.3 Efficiency
   12.4 Pressure drop and air flow rate
   12.5 Arrestance and dust holding capacity
   12.6 Marking
Annex A (normative) - Electrostatic discharging test
        procedure
   A.1 General
   A.2 Test method for discharging of filter material
        A.2.1 Equipment
        A.2.2 Preparation of test samples
        A.2.3 Measurement of the filter medium efficiency
        A.2.4 Isopropanol test
   A.3 Expression of results
   A.4 Report
Annex B (informative) - Shedding from filters
   B.1 General
   B.2 Shedding
        B.2.1 Particle bounce
        B.2.2 Release of fibres or particulate matter
               from filter material
        B.2.3 Re-entrainment of particles
   B.3 Testing
   B.4 References
Annex C (informative) - Commentary
   C.1 General
   C.2 Classification
   C.3 Test
        C.3.1 Test aerosol
        C.3.2 Loading dust
        C.3.3 Distribution and sampling of aerosols
        C.3.4 Particle counter characteristics
        C.3.5 Flat sheet test
   C.4 Filtration characteristics
        C.4.1 General
        C.4.2 Pressure drop
        C.4.3 Discharged efficiency
Annex D (informative) - Pressure drop calculation
Annex E (informative) - Example of a completed test report
   E.1 Example of test reports
   E.2 Examples of calculations
   E.3 Final results at 450 Pa
Bibliography

BS EN 779