Bsi bs en 13443 2 2005 + a1 2007

untitled BRITISH STANDARD BS EN 13443 2 2005 +A1 2007 Water conditioning equipment inside buildings — Mechanical filters — Part 2 Particle rating 1 4m to less than 80 4m — Requirements for performance[.]

Part 2: Particle rating 1 4m to less than

80 4m — Requirements for performance,

safety and testing

The European Standard EN 13443-2:2005, incorporating amendment

A1:2007, has the status of a British Standard

ICS 13.060.20; 91.140.60

This British Standard was

published under the authority

of the Standards Policy and

Amendments issued since publication

NORME EUROPÉENNE

EUROPÄISCHE NORM June 2007

English Version Water conditioning equipment inside buildings - Mechanical

filters - Part 2: Particle rating 1 µm to less than 80 µm - Requirements for performance, safety and testing

Appareils de traitement d'eau à l'intérieur des bâtiments -

Filtres mécaniques - Partie 2: Particules de taille 1 µm à 80

µm - Exigences de performances, de sécurité et essais

Anlagen zur Behandlung von Trinkwasser innerhalb von Gebäuden - Mechanisch wirkende Filter - Teil 2: Filterfeinheit 1 µm bis 80 µm - Anforderungen an Ausführung, Sicherheit und Prüfung

This European Standard was approved by CEN on 24 December 2004 and includes Amendment 1 approved by CEN on 10 May 2007 CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN Management Centre or to any CEN member

This European Standard exists in three official versions (English, French, German) A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as the official versions

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom

EUROPEAN COMMITTEE FOR STANDARDIZATION

C O M I T É E U R O P É E N D E N O R M A L I S A T I O N

E U R O P Ä I S C H E S K O M IT E E F Ü R N O R M U N G

Management Centre: rue de Stassart, 36 B-1050 Brussels

© 2007 CEN All rights of exploitation in any form and by any means reserved

worldwide for CEN national Members Ref No EN 13443-2:2005+A1:2007: E

Contents Page

Foreword 3

1 Scope 4

2 Normative references 4

3 Terms and definitions 4

4 Symbols and abbreviations 8

5 Design requirements 9

6 Performance requirements 10

7 Test procedures 11

8 Technical documents, labelling and marking 38

Annex A (informative) Typical test reports 40

Annex B (informative) Typical graphical representation of test results 46

Annex C (normative) Integrity inspection and measurement of first bubble point 50

Annex D (normative) !Installation, operation and maintenance 53

Bibliography 57

This document includes Amendment 1, approved by CEN on 2007-05-10

This document supersedes EN 13443-2:2005

The start and finish of text introduced or altered by amendment is indicated in the text by tags ! "

a) this document provides no information as to whether the product may be used without restriction in any of the Member States

b) it should be noted that, while awaiting the adoption of verifiable European criteria, existing national regulation concerning the use and/or the characteristics of this product remain in force

This is the second part of the two-part standard for mechanical filters Part 1 is concerned with mechanical filters with a particle size rating from 80 µm to 150 µm

According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom

1 Scope

This document specifies requirements relating to the construction, performance and methods of testing for mechanical filters for the removal of suspended matter in drinking water installations inside buildings It applies to filters with a filtration rating from 1 µm up to less than 80 µm and which are intended for use in systems with a minimum pressure rating of PN 6, connections between DN 15 and DN 100 and service temperature of less than

30 °C

This document is applicable to back-washable filters, integral filters and those designed for replaceable cartridges

It only concerns units that are permanently connected to the mains supply at point of entry or point of use

Part 1 of this standard (EN 13443-1) is a separate document and deals with filters with a particle rating between

80 µm and 150 µm

The following referenced documents are indispensable for the application of this document For dated references, only the edition cited applies For undated references, the latest edition of the referenced document (including any amendments) applies

EN 872, Water quality — Determination of suspended solids — Method by filtration through glass fibre filters

EN 1717, Protection against pollution of potable water in water installations and general requirements of devices to

prevent pollution by backflow

EN 13443-1:2002, Water conditioning equipment inside buildings — Mechanical filters — Part 1: Particle rating

80 µm to 150 µm — Requirements for performances, safety and testing

ISO 304, Surface active agents — Determination of surface tension by drawing up liquid films

ISO 1219-1, Fluid power systems and components — Graphic symbols and circuit diagrams — Part 1: Graphic

symbols

ISO 4021, Hydraulic fluid power — Particulate contamination analysis — Extraction of fluid samples from lines of

an operating system

ISO 12103-1, Road vehicles — Test dust for filter evaluation — Part 1: Arizona test dust

3 Terms and definitions

For the purposes of this document, the following terms and definitions apply

3.1

average pore diameter (DMP)

value, in µm, of the pore diameter which corresponds to the mode of the relative frequency of pore diameter distribution of a filter media determined by air porosimetry

3.2

cumulative mean filtration efficiency per period (Ed p)

cumulative efficiency calculated from the total numbers of particles greater than size d counted upstream and downstream of a filter during the period p

3.8

cumulative overall mean filtration efficiency (Edg )

cumulative efficiency calculated from the total number of particles greater than size d counted upstream and

downstream of a filter during the whole test

3.11

differential pressure at the inflexion point (dPi )

differential pressure across the filter unit including the cartridge at the inflexion point, minus the differential pressure generated by the test container alone (see Figure B.4)

3.17

filter system

complete installation comprising the filter housing, isolation valves, pressure gauges, pipework, etc

3.18

final differential pressure (dPF )

differential pressure of the filter element at the end of testing

ISO Coarse Test Dust (ISO CTD)

siliceous test powder having a particle size distribution by convention between 0 µm and 200 µm in accordance with ISO 12103-1

NOTE It may also be referred to as ISO 12103-1 A4 dust

3.22

ISO Medium Test Dust (ISO MTD)

siliceous test powder having a particle size distribution by convention between 0 µm and 80 µm in accordance with ISO 12103-1

NOTE It may also be referred to as ISO 12103-1 A3 dust

3.23

mechanical filter

appliance designed to remove particulate matter from water by passage of the water through a porous medium

3.24

net differential pressure (dPN )

difference between the final differential pressure of the clogged filter element and the differential pressure across the clean filter element (see 3.8)

3.25

nominal flow rate

flow rate for the filter specified by the manufacturer or, in the absence of this specification, the flow rate through the clean filter element at which the pressure drop across the filter element is 20 kPa

3.26

particle shedding

release of particles of the filter element construction material into the filtered water

3.27

reference filtration rating (S)

dimension, in µm , of the ISO MTD or ISO CTD particles at which the overall mean cumulative filtration efficiency of

total mass of injected contaminant (M i)

mass of ISO MTD or ISO CTD injected into the test circuit up to the point when the specified final differential pressure is reached

4 Symbols and abbreviations

The generic symbols and abbreviations used in this document are given in Table 1

Table 1 — Symbols and abbreviations

dP

dP

Ed Cumulative filtration efficiency at the size greater than d µm %

E[d1 ; d2] Differential filtration efficiency (between the sizes d1 and d2) %

M

N

N[d

1 ; d

2] Number of particles having a dimension greater than or equal to d

1 and less than d

Q

T

Back-washable filters shall be fitted with a free drain outlet in accordance with EN 1717

Back-washable filters shall be designed so that there shall be no interruption of the water supply during the backwash operation

5.4 Cartridge filters

Cartridge filters shall be designed such that the filter cartridge can be replaced with minimum risk of contamination

of the drinking water supply

Any tools used in this operation shall not come into contact with the drinking water and shall be provided by the filter manufacturer

The cartridge sealing arrangement shall be designed to accommodate regular cartridge change without wear of the housing which could cause degradation of the efficiency of the filter over its lifetime

Replacement cartridges shall be individually wrapped to prevent contamination in transport and storage

NOTE It is recommended, particularly for point of use filters, that a device should be provided to warn the end-user when the cartridge has become fouled

5.5 Integral filters

Integral filters shall be designed such that the filter unit can be changed without the use of special tools They shall

be installed allowing adequate access for the routine filter change operation

6 Performance requirements

6.1 Reference filtration rating

The filter system or cartridge, when tested in the manufacturer’s recommended housing, shall demonstrate a filtration efficiency of at least 99,8 % at the manufacturer’s designated particle rating for the cartridge, and at the manufacturer’s recommended maximum pressure drop, when tested in accordance with the method defined in 7.1

6.2 Retention capacity

The retention capacity shall be not less than the manufacturer’s declared value (if any), and tested in accordance with 7.2 This requirement is not applicable to back-washable filters

6.3 Clean pressure drop

The manufacturer of the filter element shall identify in the appropriate documentation, the pressure drop through a clean cartridge at the manufacturer’s recommended flow rate or the maximum acceptable pressure drop after backwash at the manufacturer's recommended flow rate (see Clause 8) The method for measurement of the clean pressure drop shall be in accordance with 7.3

6.4 Maximum pressure drop

The manufacturer of the filter element shall specify in the appropriate documentation and/or on the filter element and/or on the filter housing, the maximum pressure drop at which it is recommended that the cartridge be changed

6.5 Cartridge collapse pressure

When subjected to continuous and progressive blinding, up to a pressure drop equivalent to 80 % of the nominal pressure rating of the housing, there shall be no discontinuity in the pressure rise, nor, after careful removal and cleaning, any visible damage to the cartridge, when tested in accordance with 7.4

6.6 Cartridge cyclic differential pressure resistance

When subjected to a cyclic flow of water sufficient to generate a peak pressure drop of 200 kPa, or greater, at a cycle frequency of 0,05 Hz, for 500 cycles (see 7.5):

a) the pressure drop at the peak flow rate, shall not fall off during the test,

b) there shall be no visible evidence of damage to the filter cartridge and

c) the bubble point for the cartridge after the test shall not differ from that measured before the test, by more than

15 % The bubble point shall be measured in accordance with Annex C

6.7 Particle shedding

When subjected to the manufacturer’s recommended flow rate, a new cartridge, after preconditioning in accordance with the manufacturer’s instructions (see Clause 8), shall show no increase in particle count when compared to the background particle count of the test rig, when tested in accordance with 7.6

6.9 Housing resistance to cyclic pressure

When subjected to a cyclic pressure test as defined in EN 13443-1:2002, 7.4, the filter housing shall show no permanent, visible signs of leakage, permanent deformation, fissures or ruptures

100 mg/l The filtration efficiency and ratio are calculated from automatic, on line, particle counts upstream and downstream of the element during the low (5 mg/l) concentration periods The retention capacity is determined from the mass of contaminant required for obtaining a predetermined differential pressure Several operating parameters are specified as a function of the type of filter under test, e.g the standard flow rate of 15 l/min is recommended for testing a standard 250 mm long cartridge

7.1.2 Test equipment and materials

Key

3 Temperature sensor regulator 12 Micro-filtered water supply

7 Counter pressure control valve 16 Injection circuit n° 1

a) conical bottom reservoir having a recommended cone angle less than or equal to 90° It shall have a retention time of 30 s and an aspect ratio of 2 to 3 The recycled water return line penetrates beneath the free face so as

to avoid the risk of air entrainment;

d) instruments for measuring the flow rate, the temperature, the relative and differential pressures at the filter connections The pressure tappings are of the spur type;

e) sampling devices in accordance with ISO 4021 are placed upstream and downstream of the filter in order to ensure representative sampling of the water and contaminant;

f) interconnecting pipe and fittings, dimensioned and selected so as to ensure a turbulent flow throughout the whole circuit, thereby preventing the formation of traps, segregation and quiescent zones The length of the piping shall be reduced to the minimum;

g) clean water level control device in the test reservoir, which regulates the level to within 5 %;

h) temperature regulator which controls the temperature at the specified value of (23 ± 2) °C

7.1.2.1.2 Contaminant injection circuits

There are two injection circuits; one is allocated to 5 mg/l injection (injection circuit N° 1), the other to 100 mg/l injection (injection circuit N° 2)

Each injection circuit includes the following equipment:

a) conical bottom reservoir having a recommended cone angle less than or equal to 90° Its height is preferably between twice or three times its diameter It is equipped with a level indicator The recycled water returns beneath the free face;

b) recirculation pump which generates a sufficient flow rate to ensure perfect mixing under all circumstances It shall be resistant to the test contaminant and it shall not modify its particle size distribution An additional stirrer can be used to ensure more perfect mixing and suspension of the ISO CTD;

c) temperature regulation device to control the water temperature at that specified for the test;

d) decontamination filter, installed so as to by-pass the injection loop, which allows the water to be restored to less than 1 200 particles greater than 5 µm per 100 ml;

e) contaminant injection pump which draws the concentrated contaminant into the recirculation system at a point where the flow is turbulent and discharges it via a flexible pipe into the main pump suction or into the tank of the main circuit It shall not generate any excessive flow rate pulsation and shall have no effect on the contaminant The injection flow rate shall be sufficient to prevent segregation of the test dust;

f) sampling device conforming to ISO 4021;

g) device for measuring the injection flow rate, insensitive to the contaminant and without effect on its particle size distribution at the concentrations scheduled for the test

7.1.2.2 Automatic particle counting devices

These devices comprise one or two counters and two optical units

These devices operate on the principle of the absorption of a beam of white light or of a laser beam or on the laser diffusion principle; they have to be properly calibrated using certified monosized latex spheres

Ascertain that the high and low detection limits for the device are compatible with the counting thresholds specified

in 7.1.4.1.2.1, Table 3

7.1.2.3 Test fluid

Mains water filtered so as to contain less than 300 particles greater than 5 µm per 100 ml

NOTE To avoid precipitation of calcium carbonate, the test water hardness should preferably be less than

7.1.2.6 Ultra clean bottles

Use thoroughly cleaned sample bottles which contain less than 300 particles greater than 5 µm per 100 ml when

filled with micro-filtered water

7.1.2.7 Pigment and paint shaker

7.1.3 Test rig validation

7.1.3.1 General

The purpose of the validation is to demonstrate that the test rig complies with the test requirements The validation shall be carried out regularly at least twice a year, and whenever a component of the installation is modified or changed

7.1.3.2 Validation of the injection circuits and of the decontamination filter

The two injection circuits for attaining test concentrations of 5 mg/l and 100 mg/l shall be successively validated

The validation is conducted with the maximum volume (ViM) in each tank and at the minimum flow rates for the injection circuits

a) Calculate the two injection circuit contamination concentrations so that the concentration in the test circuit

Ce = 5 mg/l (injection circuit N° 1) or Ce = 100 mg/l (injection circuit N° 2):

) / ( e i

b) Prepare a mass M of test dust ISO MTD or ISO CTD, previously dried at a temperature between 110 °C to 150

°C for at least 1 h and cooled to room temperature in a desiccator, to obtain the previously calculated

M is the mass of test dust, in mg;

ViM is the maximum volume of each tank, in l;

Ci is the infection circuit contaminant concentration, in mg/l

c) Disperse the contaminant in 200 ml of clean water ensuring complete homogenisation (e.g by using ultrasonics and then mixing with a non-magnetic stirrer)

d) Introduce the fluid volume (ViM = 200 ml) into the injection reservoir, start the recirculation pump

(see Figure 1, item 10), introduce the test contaminant prepared in b) and c) above, and allow to circulate for a few minutes

e) Set the injection flow rate at the minimum Q i value, continuously controlling the value displayed by the flow rate meter (see Figure 1, items 6B or 6C) and the height of the fluid in the injection reservoir Start the injection into the test reservoir

NOTE It is preferable to inject the contaminant by means of a flexible pipe in order to facilitate the sampling operations at the injection point

f) Every 30 min, during a 6 h period, take a 200 ml sample via sampling valve (see Figure 1, item 4D) and at the injection point in the main circuit Determine suspended solids concentration in accordance with EN 872

g) During the course of the validation of injection circuit N° 2 (to verify Ce = 100 mg) and with a view to validating the decontamination filter, carry out, between two sampling operations, a 15 min phase of on-line counts by connecting a sensor and a counter to take-off (see Figure 1, item 4E)

h) The injection circuit is validated if the following conditions are satisfied:

 average of the flow rates, the measured maximum values and the defined injection flow rate Qi, do not differ by more than 5 %;

 suspended solids for each of the injection concentrations do not differ by more than 5 %

i) The decontamination filter is validated, if all the counts conducted in g) of this clause are less than

300 particles greater than 5 µm per 100 ml

7.1.3.3 Validation of the test circuit

a) Adjust the volume of the fluid VF in the main circuit to (7,5 ± 0,375) l

b) After fitting a tubular sleeve in place of the filter cartridge to be tested, set up the temperature regulation

system and the main pump adjusting the main flow rate Qe to 15 l/min Operate until the conditions have stabilised and, if necessary, readjust the fluid volume in the circuit to 7,5 l

c) To the upstream and downstream sample valves (see Figure 1, items 4B and 4C), connect on-line automatic counters previously calibrated, regulating the flow rate through the sensors to the values recommended by the manufacturer of the automatic counters

d) Introduce into the reservoir of each injection circuit, mass M1 and M2 of contaminant, previously oven-dried

and desiccated, to obtain the theoretical concentrations Ce = 5 mg/l and Ce = 100 mg/l

e) Start the validation with a 30 min phase at the test concentration Ce = 5 mg/l during which in-line counts are carried out, via upstream and downstream sample valves (see Figure 1, items 4B and 4C), for 30 s every minute, at the thresholds selected in Tables 2a and 2b During this phase, collect the entire volume downstream of one of the on-line counters and determine its suspended solids concentration in accordance with EN 872

f) Shut off the upstream sampling valve (see Figure 1, item 4B)

g) Follow this by a 15 min phase with a concentration Ce = 100 mg/l Collect the entire volume which has run off via downstream sampling valve (see Figure 1, item 4C) for particle size analysis, the downstream sensor having been previously disconnected

h) Finish with a 30 min phase at a 5 mg/l test concentration with on-line counts each minute via upstream and downstream sampling valves (see Figure 1, items 4B and 4C), on 25 ml sample volume, at the thresholds selected in Tables 2a and 2b

i) The test circuit is validated, if the following three conditions are satisfied:

 difference between the results for each sensor during the course of the phases described in e) and h) of this clause is less than or equal to that given in Table 2a:

Table 2a — Percentage of variation in the number of particles per counter

EXAMPLE If the flow rate through the sensor Qech = 20 ml/min during the course of a 30 min phase at 5 mg/l, the following mass shall theoretically be recovered:

mg3000

1

530

Cech is the recovered concentration of the average sample, in mg/l;

Vech is the total volume of sample recovered, in l

The following condition shall apply:

m’1 = m1 ± 30 %

7.1.4 Procedure

The following operating conditions shall be used:

a) test flow rate: manufacturer's specified flow rate as defined on the product label;

b) test contaminant: ISO MTD or ISO CTD;

c) sampling method: during Ce = 5 mg/l phases upstream (sampling valve see Figure 1, item 4B) and downstream (sampling valve see Figure 1, item 4C) of the filter;

d) counting method: on-line automatic particle counter using diffusion or absorption of white light or laser beam; e) level of initial cleanliness:

 injection circuit: less than 6 000 particles greater than 2 µm per 100 ml;

 main circuit up to take-off (see Figure 1, item 4B): less than 800 particles greater than 2 µm per 100 ml; f) duration of phases:

1) counting phase (Ce = 5 mg/l) : 30 min;

2) clogging phase (Ce = 100 mg/l) :

 surface cartridge: 60 min;

 depth cartridge: 15 min (wound, bonded);

g) end of test minimum differential pressure:

(e.g pleated, strainers, …)

(e.g wound, bonded, …)

back-washing process

7.1.4.1.2.1 Selection of counting thresholds

The counting thresholds to be used are adapted to the presumedreference filtration rating of the filter to be tested according to Table 3 below

Table 3 — Counting thresholds as a function of the designated reference rating of the filter to be tested

Designated filtration rating

7.1.4.1.2.2 Initial downstream cleanliness level

The initial cleanliness level of the test circuit measured via downstream sampling valve (see Figure 1, item 4C) shall be such that the number of particles of a size greater than the reference rating is no more than 10 % of the expected number of particles at this threshold downstream of the filter This expected number is calculated from the number of the test contaminant particles at 5 mg/l and the filter presumed efficiency at this threshold

7.1.4.2 Preparation of the contaminant injection circuits

7.1.4.2.1 Calculation of the test conditions for injection circuit N° 1 (5 mg/l test concentration)

NOTE 1 The preparation for the test presupposes a prior knowledge of the retention capacity of the filter element to be tested at the specified final differential pressure If this capacity is not known, a preliminary test is conducted at the flow rate scheduled for the test and with an exceptionally high concentration of test contaminant upstream of the filter (between 100 mg/l and 300 mg/l)

a) Taking the concentration Ce = 100 mg/l upstream of the filter under test, calculate the time T’1 in minutes required for clogging the filter element:

C

Qe = 15 l/min

b) From T’1 calculated in a) of this clause, determine the number PT of 1 h phases in the case of a pleated filter, and of 15 min phases in the case of a depth filter, at a 100 mg/l test concentration required for clogging the filter and the number of 30 min phases at a 5 mg/l test concentration based on start and finish with a 5 mg/l phase

EXAMPLE If T’ = 2h 30 for a pleated filter, provide for:

 at least two 1 h phases with Ce = 100 mg/l and

 three 30 min phases with Ce = 5 mg/l

For a depth filter provide for:

 at least three 15 min phases with Ce = 100 mg/l and

 four 30 min phases with Ce = 5 mg/l

c) Select the injection flow rate value (Qi1) as a function of the sampling flow rates upstream and downstream of the filter under test and of a possible additional draw-off flow rate in order to guarantee the stability of the fluid volume in the main circuit throughout the test The sampling flow rates are set to the flow rates imposed by the particle counters

d) Calculate the total volume V i1 in litres of fluid required for injecting the contaminant during the time period T1(min) scheduled for the test from the injection flow rate Q i1 (l/min) and adding a safety margin of 20 %:

NOTE 2 This total volume V

i1 can be prepared as required during the course of testing

e) Calculate the concentration Ci1in milligram per litre of the contaminant in injection circuit N° 1:

i1

e e

i1

Q

Q C

1

Q C

(6)

7.1.4.2.2 Calculation of the test conditions for injection circuit N° 2 (100 mg/l test concentration)

a) Select the injection flow rate value (Qi2) as a function of the sampling flow rates upstream and downstream of the filter under test and of a possible additional draw-off flow rate in order to guarantee the stability of the fluid volume in the main circuit throughout the test The sampling flow rates are set to the flow rates required for the particle counters

b) Calculate the total volume Vi2 in litres of fluid required for injecting the contaminant during the time period T1(min) scheduled for the test calculated in a) above, from the injection flow rate Qi2(l/min) and adding a safety margin of 20 %:

NOTE This total volume V

i2 can be prepared as required during the course of testing A greater volume can be prepared provided that the contaminant concentration conforms to that calculated in a) of this clause

c) Calculate the concentration Ci2 (mg/l) of the contaminant in injection circuit N° 2:

i2

e e

i2

Q

Q C

(8) where

2

Q C

(9)

7.1.4.2.3 Setting up injection circuits

a) Fill up the injection reservoirs and start the recirculation pumps

b) Set the injection flow rates at the values selected in 7.1.4.2.1 c) and 7.1.4.2.2 a)

c) Put the decontamination filters of the injection circuits (see Figure 1, item 8C) into service and operate the systems until they contain less than 6 000 particles greater than 2 µm per 100 ml

d) By-pass the decontamination filters (see Figure 1, item 8C)

e) Accurately measure the fluid volumes (Vi) in the injection circuits and add to each reservoir the mass M of

contaminant determined in 7.1.4.2.1 f) and 7.1.4.2.2 d) previously dispersed in a small quantity of water sampled from the injection circuits taking care to properly rinse the containers

NOTE Special attention should be paid to the dispersion of the high concentration contaminant It is recommended to pour the completely dehydrated test dust into a bottle with a screw-cap having a capacity of 80 times the bulk volume of the contaminant, then to introduce a volume of fluid equal to 50 times this same bulk volume The bottle is immersed in an ultrasonic tank for 1 min, then placed for 10 min in a pigment and paint shaker

f) Operate the injection circuits for 10 min in order to homogenise the suspensions prior to starting to inject the contaminant into the test circuit

c) Start the circulation pump and the temperature regulation system Set the flow rate at the test value

Qe = (15 ± 0,3) l/min and the temperature at (23 ± 2) °C In the case of an open circuit, adjust the mains

make-up water flow rate in order to take into account the filtrate rejection and the sampling flow rates

NOTE To ensure repeatable results the circuit water volume should remain constant within ± 5 % throughout the test duration

d) Circulate the water through the test circuit decontamination filter until the particulate contamination levels reach the values specified in 7.1.4.1.1 (sampling valve 4B in Figure 1) and 7.1.4.1.2.2 (sampling valve 4C in Figure 1) and remain stable for at least 15 min If necessary, install an additional decontamination filter in place

of the filter under test

e) Note the differential pressure ∆Pc across the filter housing alone

7.1.4.4 Filter efficiency and retention capacity test

a) Stop the main pump

b) Install the filter element to be tested into the test housing and make sure to completely fill it up with test fluid In the case of a pleated cartridge, its integrity shall have been previously established in accordance with Annex C

c) Circulate the water at the specified test flow rate to within ± 2 % and control the temperature at (23 ± 2) °C d) Take three successive samples from each injection circuit and determine suspended solids concentration in accordance with EN 872

e) Set the particle counter thresholds at the values defined in Table 3 Start the counters

f) Leave the decontamination filter in operation

g) Record the results obtained over a 5 min period in order to measure the initial cleanliness level

h) Measure the differential pressure (∆Po) across the clean filter The value obtained allows the determination of the differential pressure of the clean filter element (∆Peo) by subtraction of the differential pressure of the filter housing alone (∆Pc) as measured in 7.1.4.3 (∆P eo = ∆P o – ∆Pc)

i) Begin the test by starting the stop-watch and the injection pump of circuit N° 1 to obtain an upstream

concentration Ce = 5 mg/l Alternate periods of 30 min at Ce = 5 mg/l with 60 min for pleated cartridges, or

15 min for depth cartridges, at Ce = 100 mg/l

j) Operate the sampling devices upstream and downstream of the filter and count the particles for 30 s every

minute during the periods where Ce = 5 mg/l Interrupt the upstream counts by isolating the sensor with

upstream sampling valve (see Figure 1, item 4B) during the periods at Ce = 100 mg/l

k) Collect all of the fluid from the downstream sensor and measure the total final volume collected

l) The test is continued until the differential pressure (dPF) of the element reaches 250 kPa (pleated cartridge),

150 kPa (depth cartridge) If at the end of 6 h this value is not reached, stop the test

Where clogging occurs during a 100 mg/l phase, pass immediately to a 5 mg/l injection level and continue the test for 30 min

For a depth cartridge, if clogging has not occurred by the end of 6 h, start the test again under the conditions given for a pleated cartridge

If the differential pressure, after a rapid development, levels off and is maintained for 30 min, then the test is

terminated by a last 30 min counting phase at Ce = 5 mg/l

m) Stop the test as follows:

 note the end of test time (TF) and the duration of the last clogging period at 100 mg/l (∆t100, PT );

 disconnect the particle counters;

 stop the main circuit pump;

 note the fluid volume (VF) in l in the test circuit;

 note the volume of the injection circuits and take three successive samples and determine suspended solids concentration in accordance with EN 872;

 stop the injection circuit pumps;

 thoroughly mix the volume of fluid collected from the downstream sensor Take a sample and determine suspended solids concentration in accordance with EN 872

7.1.5 Expression of results

From the concentration value and the fluid volume recovered from the downstream sensor, calculate the mass of

ISO MTD or ISO CTD not retained during each period Determine the retention capacity (CR)by subtracting the non-retained mass of ISO MTD or ISO CTD from the injected mass of ISO MTD or ISO CTD

NOTE The mean of injected test dust lost by the upstream sampling line during phases at Ce= 5 mg/l is considered negligible

Calculate from the cumulative and differential mode particle counts the cumulative and differential filtration efficiencies

Graphically determine the reference filtration rating (S)

7.1.6 Test report

In addition to the reference to this document, the test report shall give the following information:

a) name of test laboratory;

m) initial cleanliness level of the system upstream and downstream;

n) end of test or final differential pressure;

o) type and reference of the sensors and particle counters;

p) injected mass;

q) total non retained mass;

r) table depicting cartridge fouling with time;

s) curves and tables of the cumulated and differential, upstream and downstream, raw instantaneous counts vs test time;

t) cumulative overall mean filtration efficiency, per period and for all test vs particle size;

u) calculated reference filtration rating S in µm;

v) calculated retention capacity: CR !deleted text" in g;

w) an example of a test report is given Annex A, A.1 and examples of efficiency curves are given in Annex B,

Figure B.1

7.2 Retention capacity

7.2.1 Principle

The retention capacity of a cartridge may be measured either while performing an efficiency test as defined in 7.1

or using the simplified protocol described below

NOTE Depending on the type and the characteristics of the cartridge, the retention capacities obtained by the two protocols may differ Only values measured with the same one are to be compared

Use a filter test stand as specified in 7.1.2.1 with only one injection circuit (N° 2)

7.2.3 Procedure

a) test flow rate: specified flow rate as defined on the product label;

b) test contaminant: ISO MTD or ISO CTD;

c) level of initial cleanliness:

 injection circuit: not more than 6 000 particles greater than 2 µm per 100 ml;

 main circuit up to take-off (see Figure 1, item 4B): not more than 800 particles greater than 2 µm per

100 ml;

d) end of test minimum differential pressure:

 surface cartridge (e.g pleated, strainers, ): ∆PF = 250 kPa;

 depth cartridge (e.g wounded, bonded, ) : ∆PF = 150 kPa;

e) backwashable filters: manufacturer's specified differential pressure that starts the back-flushing process

7.2.3.2 Preparation of the contaminant injection circuit

Using the procedure described in 7.1.4.2.2, prepare the injection circuit so as to clog the element at the differential pressure stated in 7.2.2.1

7.2.3.3 Preparation of the test circuit

Proceed per 7.1.4.3 adopting the initial contamination levels specified in 7.2.2.1

7.2.3.4 Retention capacity test

a) Stop the main pump and, in the case of an open circuit, isolate the mains water supply

b) Install the filter element to be tested into the test housing or the filter body In the case of a pleated cartridge, its integrity shall have been previously controlled in accordance with Annex C

c) Circulate the water at the specified test flow rate to within ± 2 % adjusting, if necessary, the make-up water supply and control the temperature at (23 ± 2) °C

d) Take three, successive samples from the injection circuit and determine their concentration by gravimetric analysis in accordance with EN 872

e) For a closed circuit, leave the decontamination filter in operation

f) Measure the differential pressure (∆Po) across the clean filter The value obtained allows the determination of the differential pressure of the clean filter element (∆Peo) by subtraction of the differential pressure of the filter body alone ∆Pc as measured in 7.1.4.3 (∆Peo = ∆Po – ∆Pc)

g) Begin the test by starting the stop-watch and the injection pump to obtain an upstream concentration

Stop tests as follows:

 note the end of test time (TF);

 stop the main circuit pump and shut off, if necessary, the mains water supply;

 note the fluid volume (VF) in the test circuit;

7.2.4 Expression of results

From the concentration value and the fluid volume recovered from the downstream sampling device, calculate the

mass of ISO MTD or ISO CTD not retained during the test Determine the retention capacity (CR)by subtracting the

non-retained mass of ISO MTD or ISO CTD from the injected mass of ISO MTD or ISO CTD

7.3 Differential pressure

7.3.1 Principle

The test consists of imposing an increasing !flow rate" of water through the filter housing with and without the filtering element and measure the corresponding differential pressure

7.3.2 Test equipment and materials

The test rig diagram is given on Figure 2

Key

5 Thermometer

Figure 2 — Typical layout of a rig for determining the differential pressure

of a filter element versus flow rate

The basic components of this test rig are:

a) source of pressurised water capable of supplying a flow rate 20 % greater than the maximum test !flow rate" A suitable control device shall allow continuous variation of !flow rate" from zero to the desired value;

b) if required, use a reservoir that prevents air entrapment and air ingression;

c) temperature gauge and regulator at (23 ± 2) °C;

d) clean-up filter with reference filtration rating less than 1/5 of that of the test filter;

e) pressure tappings installed on a straight pipe on both side of the filter at a distance equal to approximately

6 times the inside diameter upstream and 4 times the downstream diameter;

f) test fluid: tap water freshly microfiltered

Use instruments with the precision as follows:

 flow rate: ± 2 % of actual value;

 pressure: ± 2 % of actual value;

 temperature: ± 0,5 °C

7.3.4 Procedure

7.3.4.1 Test rig validation

Install the filter housing without element Circulate the test fluid at 1,2 QN, where QN is the nominal fluid flow rate, until the temperature stabilises at (23 ± 2) °C and, if necessary, until the circuit is clean Ensure the absence of air and the stability of pressure values

7.3.4.2 Test of the filter housing

a) First ensure that, without filter element, water flow is not significantly modified by the housing If there is flow perturbation, install a substitute element (e.g a perforated tube) that creates a flow path as similar as possible

to that caused by the filter element The section for passage through the substitute element shall be as large

as possible to minimise the pressure drop The characteristics of this substitute element shall be described in the test report

b) Adjust the flow rate to 0,2 QV and note P1 and ∆P as well as the test liquid temperature

c) Repeat these operations for increasing flow rate values corresponding to increments of 0,2 QV up to 1.2 QV d) For each flow rate increment calculate and record the differential pressure across the filter housing

7.3.4.3 Test of the complete filter

a) Install the filter element in the filter housing and mount the assembly on the test rig Make sure that the bypass

is fully closed

b) Establish circulation in order to expel the air from both the filter housing and the circuit

c) Repeat the above operations in 7.3.4.2 b) to d), taking care to observe the same flow rate increments

7.3.4.4 Characteristics of the filter element only

Calculate the pressure drop generated by the filter element only, by deducting the values obtained with the housing only, from those measured on the filter housing together with its filter element

7.3.5 Test report

Report all test conditions and results Plot curves ∆P = f(QV) for the housing alone, for the complete assembly and for the filtering cartridge alone

A typical test report is given in Annex A, A.2 and a typical test curve in Annex B, Figure B.3

7.4 Cartridge collapse pressure