---

NOTE 1 There is no burn-back resistance level A for class III.

NOTE 2 Typical extinguishing performance classes and burn-back resistance levels for different types of foam concentrate are given in Annex A.

11 Container marking

Markings on shipping containers should be permanent and legible. The following information shall be marked on the packaging or transport container:

1. the designation (identifying name) of the concentrate;

2. the words "low expansion fire-fighting foam concentrate" and the number and date of this European Standard (i.e. EN 1568-3:2008);

NOTE For low expansion concentrates which also conform to other parts of EN 1568 additional markings can be used as given in those parts.

3. if the concentrate conforms to Clause 8 the words "aqueous film-forming";

4. recommended usage concentration (most commonly 1 %, 3 % or 6 %);

5. any tendency of the foam concentrate to cause harmful physiological effects, the methods needed to avoid them and the first aid treatment if they should occur;

6. recommended maximum storage temperature and lowest temperature for use;

7. if the concentrate does not conform to Clause 7, 8.2 and 9.2 after conditioning in accordance with E.2 the words 'Do not store below 0 °С;

8. the nominal quantity in the container;

9. the supplier's name and address;

10. the batch number and the date of manufacture;

11. the words "Not suitable for use with sea water" or "Suitable for use with sea water" as appropriate;

12. if the foam concentrate is Newtonian and the viscosity at the lowest temperature for use is more than 200 mm²s'¹ when measured in accordance with EN ISO 3104 the words "This concentrate can require special proportioning equipment";

13. if the foam concentrate is pseudo-plastic and the viscosity at the lowest temperature for use is greater than or equal to 120 mPa.s at 375 s¹ the words "Pseudo-plastic foam concentrate. This concentrate can require special proportioning equipment";

n) the lowest extinguishing performance class and the lowest burn-back resistance level obtained during testing to each part of EN 1568 (if tested to more than one part) with all fuels in potable water and sea water.Annex A
(informative)
Grades of foam concentrate and performance

A.1 Grades

Foam concentrates are graded as follows:

1. protein foam concentrates (P): these are liquids derived from hydrolysed protein materials;

2. fluoroprotein foam concentrates (FP): these are protein concentrates with added fluorinated surface active agents;

3. synthetic foam concentrates (S): these are based upon mixtures of hydrocarbon surface-active agents and can contain fluorinated surface active agents with additional stabilizers;

4. alcohol resistant foam concentrates (AR): these can be suitable for use on hydrocarbon fuels, and additionally are resistant to breakdown when applied to the surface of water-miscible liquid fuels. Some alcohol resistant foam concentrates can precipitate a polymeric membrane on the surface of alcohol;

5. aqueous film-forming foam concentrates (AFFF): these are generally based on mixtures of hydrocarbon surfactants and fluorinated surface active agents and have the ability to form an aqueous film on the surface of some hydrocarbon fuels;

6. film-forming fluoroprotein foam concentrates (FFFP): these are fluoroprotein foam concentrates which have the ability to form an aqueous film on the surface of some hydrocarbon fuels.

A.2 Typical performance

The correlation between performance and grade of concentrate is not perfect. The values given in Table A.1 are therefore only typical and particular foam of a given grade can have performance better or worse than that shown.

Table A.1 —Typical performance for various grades of foam concentrate

Annex В
(normative)

Preliminary sampling of foam concentrates

The samples for testing shall be delivered by the supplier in completely filled sealable containers. The samples for testing shall be taken and delivered by the supplier using a method which will provide a representative sample of the foam concentrate to be tested.

NOTE Nominal 25-litre containers are convenient.Annex C
(normative)

Determination of percentage sediment

NOTE See Clause 4.

C.1 Sampling

Use a sample prepared in accordance with Annex B. Place approximately 1 I of the sample in a suitable container of nominal capacity sufficient to provide an ullage of 5 % to 10 % of the container volume. Seal the container. Ensure that any sediment is dispersed by agitating the sample container. Take two samples, testing one immediately at a temperature of (20 ± 5) °С, the other after ageing for (24 ± 2) h at (60 + 2) °С in a completely filled container without access to air.

C.2 Apparatus

C.2.1 Graduated centrifuge tubes

NOTE The centrifuge tubes described in ISO 3734 are suitable.

C.2.2 Centrifuge, operating at (6 000 + 600) m s’².

NOTE The centrifuge described in ISO 3734 is suitable.

C.2.3 180 pm sieve conforming to ISO 3310-1

C.2.4 Plastic wash bottle

C.3 Procedure

C.3.1 Centrifuge each sample of the concentrate for 10 min. Determine the volume of the sediment and report it as a percentage of the volume of the centrifuged sample.

C.3.2 Wash the contents of the centrifuge tube onto the sieve and check whether the sediment can be dispersed through the sieve by the jet from the plastic wash bottle.Annex D
(normative)

Determination of Viscosity for pseudo-plastic foam concentrates

NOTE The procedure is described in EN ISO 3219 Part A or B.

D.1 Pseudo-plastic foam concentrates

Pseudo-plastic foam concentrates have a viscosity which decreases with increasing shear rate at constant temperature.

NOTE Pseudo-plastic foam concentrates are a particular class of non-Newtonian foam concentrate.

D.2 Viscosity determination

D.2.1 Apparatus

Rotational viscometer in accordance with EN ISO 3219 with the following parameters:

Maximum shear stress > 75 Pa

Maximum shear rate > 600 s'¹

The viscometer shall be fitted with a temperature control unit which can maintain the sample temperature within ± 1 °С of the required temperature.

D.2.2 Test temperatures

The viscosity of the foam concentrate shall be measured from 20 °С, to and including the lowest temperature for use claimed by the manufacturer in steps of 10 °С. Use a fresh sample for each temperature.

D.2.3 Viscosity measurement

If the sample contains suspended air bubbles the sample shall be centrifuged for 10 min using the apparatus specified in C.2.1 and C.2 before the sample is applied in the apparatus.

The test should be performed according to the following test procedure:

1. adjustment of temperature control unit;

2. setting of the gap;

3. application of the sample;

4. minimum 10 min waiting period (no shear) to reach temperature equilibrium;

5. 1 min pre-shearing at 600 s ^1;

6. 1 min waiting period without shearing;

7. measure the shear stress for 10 s at each shear rate starting at the lowest shear rate (preferable at 75 s’¹).

Measure the shear stress at least at 8 different shear rates over the range (0 to 600 s’¹), e.g. 75 150’¹, 225 300'¹, 375 450'¹, 525 600 s’¹. Calculate the apparent viscosity from the Equation (D.1):

.

(D.1)

. .. і _n ,_nnn_Shearstress(Pa)

Apparent viscosity ymPa ■ s) = 1000X f P

Shearrateys J

D.2.4 Results

Report the results as a table including test temperature (°С), shear rate (s'¹), Shear stress (Pa), and apparent viscosity (mPa.s).Annex E
(normative)

Temperature conditioning of foam concentrates

E.1 General

If the foam concentrate is claimed by the supplier not to be adversely affected by storage at -30 °С, condition the sample in accordance with E.2 and then in accordance with E.3; otherwise, condition only in accordance with E.3.

E.2 Low temperature conditioning

E.2.1 Apparatus

E.2.1.1 Freezing chamber, capable of achieving a temperature of (-30 ± 3) °С

E.2.1.2 Sample containers, in accordance with Annex B.

NOTE More than one container can be needed to condition sufficient volume of foam concentrate for subsequent testing.

E.2.2 Procedure

Set the temperature of the freezing chamber to (-30 + 3) °С.

Do not agitate the content of the container(s) at any time until the sample of foam concentrate has been divided into top and bottom half-samples (see E.4).

Place the sample container(s) in the freezing chamber and maintain at the required temperature for (24 ± 1) h. At the end of this period store the container(s) for not less than 48 h and not more than 72 h in an ambient temperature of (20 ± 5) °С.

Repeat 3 times so that there are four cycles of freezing and thawing before testing.

E.3 High temperature conditioning

E.3.1 Apparatus

Oven, capable of achieving a temperature of (60 + 3) °С.

E.3.2 Procedure

Set the temperature of the oven to (60 ± 3) °С.

If the foam concentrate sample has not been conditioned in accordance with E.2 use foam concentrate sample in accordance with Annex B; otherwise use containers conditioned in accordance with E.2. Do not agitate the content of the container(s) at any time until the sample of foam concentrate has been divided into top and bottom half-samples (see E.4).

Place the container(s) in the oven and maintain at required temperature for 7 days. At the end of this period store the container(s) for not less than 48 h and not more 72 h in an ambient temperature of (20 + 5) °С.

E.4 Division into top and bottom half-samples

E.4.1 Apparatus

E.4.1.1 Top half-sample container(s)

Sealable empty container(s), suitable for the foam concentrate to be tested, of minimum half the volume of the sample container(s) as described in Annex B.

E.4.1.2 Divider device

After conditioning, the top sample from the sample container shall be divided from the bottom sample by pressurizing the sample container and force the top sample through a delivery pipe into the top sample container described in E.4.1.1. A principle sketch of the divider and sample container is shown in Figure E.1

The delivery pipe and the pressure inlet can be fitted to the lid of the original sample container. In practice it might be necessary to use different fittings depending on the design of the lid and sample container. Be sure that the fitting between divider and the lid is air tight to keep the pressure needed to force the foam concentrate through the delivery pipe.

In order to ensure that there is no mixture between the top sample and the bottom sample during the division process, the delivery pipe shall be adjustable in vertical direction. The inlet of the delivery pipe shall be conical and equipped with a plate in order to provide a horizontal flow into the pipe as shown in Figure E.1. In order to make it possible to mount the delivery pipe either the cone and plate shall be detachable or the delivery pipe shall be designed in a way that it can be mounted through the lid. Other suitable design of the divider device is permitted provided that the function is the same.

Key

1. air pressure pipe

2. delivery pipe diameter (8-15) mm

3. detachable cone and plate, diameter (25-35)mm, height (40-50)mm, distance between cone and plate (10-12)mm

4. sample container approximately 25 I

5. top sample

6. bottom sample

Figure E.1 — Example of a suitable equipment to divide the conditioned foam concentrate into
top and bottom half-samples

E.4.2 Procedure

Mount the divider device to the sample container. Adjust the delivery pipe in vertical direction so that the inlet of the delivery pipe is positioned below the surface, on a vertical distance of approximately 1/3 in to the top half-sample. Pressurize the sample container carefully and start collecting the top half-sample foam concentrate into the empty top half-sample container. Interrupt the pressurizing just before the foam liquid surface reaches the inlet of the delivery pipe. Lower the delivery pipe another 1/3 into the top half-sample and repeat the procedure twice. At the end of the dividing process, the top half-sample shall have been collected from three levels.

The bottom half-sample is preferably kept in the original sample container.

Before subsequent testing starts of the top and bottom half-samples for Clause 7, 8 and 9, the top half-container and the bottom half-sample container shall be agitated in order to provide a homogenous foam sample.

Annex F
(normative)

Determination of surface tension and spreading coefficient

NOTE See Clauses 7 and 8.

F.1 Materials

F.1.1 Solution of foam concentrate, at the recommended usage concentration in distilled water complying with EN ISO 3696 (Grade 3) or demineralized water, the water having a surface tension greater than 70 mN m'¹ when tested in accordance with F.2.1.

F.1.2 For determination of spreading coefficient only, cyclohexane of purity not less than 99 %.

F.2 Procedure

F.2.1 Surface tension

Determine the surface tension of the solution at a temperature of (20 ± 1) °С using the ring or plate method of ISO 304. In the test report state which method (ring or plate) was used.

F.2.2 Spreading coefficient

After measuring surface tension in accordance with F.2.1 introduce a layer of cyclohexane at (20 ± 1) °С onto the foam solution, being careful to avoid contact between the ring or plate and the cyclohexane. Wait (6 ± 1) min and measure the interfacial tension. Calculate the spreading coefficient between the solution and cyclohexane from the Equation (F.1):

S = T_C-T_s-T, (F.1)

where

S is the spreading coefficient in millinewtons per metre;

T_c is the surface tension of the cyclohexane determined in accordance with F.2.1 in millinewtons per metre;

T_s is the surface tension of the foam solution in millinewtons per metre;

T, is the interfacial tension between the foam solution and cyclohexane in millinewtons per metre.

In the test report state which method (ring or plate) was used.

Annex G
(normative)

Determination of expansion and drainage time

NOTE See Clause 9.

G.1 Apparatus

G.1.1 Collecting vessel, (see Figure G.1) of nominal volume 1,6 I known to ± 1 % equipped with a drain at the base.

G.1.2 Foam collector, as shown in Figure G.2

G.1.3 Foam making equipment, with nozzle as shown in Figure G.3 and G.4 which when tested with water has a flow rate of 11,4 l/min at a nozzle pressure of (6,3 + 0,3) bar.

G.1.4 Stop clock, or other timing device.

G.2 Temperature conditions

Carry out the tests under the following temperature conditions:

Air temperature (20 + 5) °С

F

(17,5 ± 2,5) °С

oam solution temperature

G.3 Procedure

G.3.1 Prepare two samples of foam concentrate in accordance with Annex B. Condition one in accordance with Annex E, to give a total of three samples (non-conditioned, bottom-conditioned, and top-conditioned).

G.3.2 Carry out the remainder of the procedure for each sample on the same day. Prepare a foam solution of each sample following the supplier's recommendations for concentration, maximum premix time, compatibility with the test equipment, avoiding contamination by other types of foam, etc.

Use potable water to make up the foam solutions and, if the supplier claims the concentrate to be suitable for sea water, also make foam solutions at the same concentration using simulated sea water prepared in accordance with G.4.

The concentration used in simulated sea water shall be the same as the concentration used in potable water.

G.3.3 Wet the vessel internally and weigh it. Record the mass (ЛА). Set up the foam equipment and adjust the nozzle pressure within the range (6,3 ± 0,3) bar to give a flow rate of 11,4 l/min. With the drain at the base closed, collect foam, taking care that voids are not formed in the vessel, starting the timing device when the vessel is half full. As soon as the vessel is full, stop collecting foam and strike the foam surface level with the rim. Weigh the vessel and record the mass (M₂).

NOTE The vessel should be cleaned from running foam outside after the strike of the foam.

Calculate the expansion E from the Equation (G.1):

where

V is the vessel volume in litres;

My is the mass of the empty vessel in kilograms;

M₂ is the mass of the full vessel in kilograms.

Assume that the density of the foam solution is 1,0 kg/l.

Open the drainage facility and measure the 25 % and 50 % drainage time. Determine the drainage either by having the vessel on a scale and recording the mass loss or by collecting the drained foam solution in a measuring cylinder. Adjust the drainage facility such that the drained foam solution can flow out whilst preventing the passage of foam. For each sample carry out the test 3 times.

NOTE This can be achieved by controlling the level of the liquid/foam interface in the plastic tube at the outlet.

G.3.4 For each sample calculate the mean values of the three tests for the expansion and 25 % and 50 % drainage time.

G.4 Simulated sea water

Prepare the simulated sea water by dissolving the following components:

All dimensions are nominal and in millimetres

1. drainage pot( Angle of slope of base nominally 11°

2. stand

3. transparent tube, 6mm to 8 mm bore30mm to

50 mm long

4. discharge outlet closure

5. measuring cylinder

1 drainage pot

NOTE Suitable materials for the Collection surface are stainless steel, Aluminium, brass or plastics.

A

Figure G.1 — Collecting vessel for
determination of expansion and drainage time

Figure G.2 — Foam collector for expansion
and drainage measurement

ll dimensions are in millimetres

Figure G.3 — Foam making nozzle (general arrangement)¹)

Dimensions in millimetres

20 ± 0,2

K1

Figure G.4 — Foam-making nozzle (details)Annex H
(normative)

Determination of test fire performance

NOTE 1 See Clause 10.

NOTE 2 The tests described in this annex are more expensive and time consuming than the other tests described in the standard. It is recommended that they are carried out at the end of the test programme, so as to avoid the expense of unnecessary testing.

H.1 General conditions

H.1.1 Test series and criteria for success

H.1.1.1 Foam concentrates not compatible with sea water

Carry out two or three tests (the third test is not necessary if the first two are both successful or if both are not successful). The concentrate conforms to Clause 10 if two tests are successful.

H.1.1.2 Foam concentrates compatible with sea water

Carry out one of the first two tests with potable water and the other with the simulated sea water of composition given in G.4. If both are successful repeat the test with the greater of the two extinction times. If the extinction times are identical repeat the sea water test. If the repeat test is successful terminate the test series. If the repeat test is unsuccessful carry out a second repeat test.