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Draft for comments only — Not to be cited as East African Standard CD/K/807:2010 ICS 71.100.40 © EAC 2010 First Edition 2010 EAST AFRICAN STANDARD Liquid toilet soap — Specification EAST AFRICAN COMMUNITY

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Page 1: EAST AFRICAN STANDARD - EAC QUALITY...6.2.2.2 Weigh out the test specimen required for the determination of free alkali or free acid content last, and test it immediately. 6.2.2.3

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CD/K/807:2010 ICS 71.100.40

© EAC 2010 First Edition 2010

EAST AFRICAN STANDARD Liquid toilet soap — Specification

EAST AFRICAN COMMUNITY

Page 2: EAST AFRICAN STANDARD - EAC QUALITY...6.2.2.2 Weigh out the test specimen required for the determination of free alkali or free acid content last, and test it immediately. 6.2.2.3

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CD/K/807:2010

ii © EAC 2010 — All rights reserved

Foreword Development of the East African Standards has been necessitated by the need for harmonizing requirements governing quality of products and services in East Africa. It is envisaged that through harmonized standardization, trade barriers which are encountered when goods and services are exchanged within the Community will be removed. In order to meet the above objectives, the EAC Partner States have enacted an East African Standardization, Quality Assurance, Metrology and Test Act, 2006 (EAC SQMT Act, 2006) to make provisions for ensuring standardization, quality assurance, metrology and testing of products produced or originating in a third country and traded in the Community in order to facilitate industrial development and trade as well as helping to protect the health and safety of society and the environment in the Community. East African Standards are formulated in accordance with the procedures established by the East African Standards Committee. The East African Standards Committee is established under the provisions of Article 4 of the EAC SQMT Act, 2006. The Committee is composed of representatives of the National Standards Bodies in Partner States, together with the representatives from the private sectors and consumer organizations. Draft East African Standards are circulated to stakeholders through the National Standards Bodies in the Partner States. The comments received are discussed and incorporated before finalization of standards, in accordance with the procedures of the Community. Article 15(1) of the EAC SQMT Act, 2006 provides that “Within six months of the declaration of an East African Standard, the Partner States shall adopt, without deviation from the approved text of the standard, the East African Standard as a national standard and withdraw any existing national standard with similar scope and purpose”.

East African Standards are subject to review, to keep pace with technological advances. Users of the East African Standards are therefore expected to ensure that they always have the latest versions of the standards they are implementing.

© East African Community 2010 — All rights reserved*

East African Community

P O Box 1096

Arusha

Tanzania

Tel: 255 27 2504253/8

Fax: 255-27-2504481/2504255

E-Mail: [email protected]

Web: www.each.int

* 2010 EAC — All rights of exploitation in any form and by any means reserved worldwide for EAC Partner States’ NSBs.

Page 3: EAST AFRICAN STANDARD - EAC QUALITY...6.2.2.2 Weigh out the test specimen required for the determination of free alkali or free acid content last, and test it immediately. 6.2.2.3

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CD/K/807:2010

© EAC 2010 — All rights reserved iii

Introduction During the preparation of this standard, reference was made to the following documents: SANS 238:2008, Liquid toilet soap SANS 5190:2004, Water insoluble matter content of soap products SANS 5222:2004, Identification of rosin in fatty matter SANS 5223:2006, Rosin content of fatty matter in soaps Acknowledgement is hereby made for assistance derived from this source.

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CD/K/807:2010

iv © EAC 2010 — All rights reserved

Contents

1 Scope ......................................................................................................................................... 1

2 Normative references ................................................................................................................. 1

3 Definitions .................................................................................................................................. 1

4 Requirements ............................................................................................................................. 2

4.1 General....................................................................................................................................... 2

4.2 Odour ......................................................................................................................................... 2

4.3 Consistency ................................................................................................................................ 2

4.4 Chemical requirements .............................................................................................................. 2

4.5 Viscosity at 25 °C ............................ ........................................................................................... 2

5 Sampling and compliance with this standard ............................................................................. 3

5.1 Sampling .................................................................................................................................... 3

5.2 Compliance with this standard ................................................................................................... 3

6 Inspection and methods of test .................................................................................................. 3

6.1 Inspection ................................................................................................................................... 3

6.2 Preparation of test specimens ................................................................................................... 3

6.3 Free alkali content or free acid content ...................................................................................... 4

6.4 Unsaponified plus unsaponifiable matter content ...................................................................... 4

6.5 Alcohol insoluble matter content ................................................................................................ 4

6.6 Fatty matter content ................................................................................................................... 4

6.7 Chloride content ......................................................................................................................... 4

6.8 Rosin content of fatty matter ...................................................................................................... 4

6.9 Viscosity at 25 °C ............................ ........................................................................................... 4

7 Packing and marking .................................................................................................................. 4

7.1 Packing....................................................................................................................................... 4

7.2 Marking....................................................................................................................................... 4

Annex A (normative) Notes to purchasers ............................................................................................. 5

Annex B (normative) Quality verification of liquid toilet soap ................................................................. 6

Annex C (normative) Identification of rosin content of fatty matter in soaps ......................................... 7

Annex D (normative) Determination of rosin content of fatty matter in soaps ....................................... 8

Annex E (normative) Water insoluble matter content of soap products .............................................. 11

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CD/K/807:2010

© EAC 2010 — All rights reserved 1

Liquid toilet soap — Specification 1 Scope This East African Standard specifies the requirements of liquid toilet soap, for personal hygiene and that is suitable for use in liquid toilet soap dispensers. 2 Normative references 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. EAS 85-3, Paints, varnishes, lacquers and enamels — Methods of test — Part 3: Determination of flow time by use of a flow cup ISO 456, Surface active agents — Analysis of soaps — Determination of free caustic alkali ISO 457, Soaps — Determination of chloride content — Titrimetric method ISO 673, Soaps — Determination of content of ethanol-insoluble matter ISO 684, Analysis of soaps — Determination of total free alkali ISO 685, Analysis of soaps — Determination of total alkali content and total fatty matter content ISO 862, Surface active agents — Vocabulary ISO 1067, Analysis of soaps — Determination of unsaponifiable, unsaponified and unsaponified saponifiable matter ISO 4314, Surface active agents — Determination of free alkalinity or free acidity — Titrimetric method ISO 4315, Surface active agents — Determination of alkalinity — Titrimetric method ISO 4323, Soaps — Determination of chlorides content — Potentiometric method 3 Definitions For the purpose of this standard the definitions given in ISO 862 and the following shall apply. 3.1 batch soap manufactured from one boil or, in the case of continuous production processes, the material from a single day’s production 3.2 boil soap from pan or vat 3.4 defective soap or its container that fails in one or more respects to comply with the appropriate requirements of the specification

EAST AFRICAN STANDARD

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2 © EAC 2010 — All rights reserved

3.5 lot that quantity of soap powder or chips bearing the same batch identification and from one manufacturer, submitted at any one time for inspection and testing 3.4 unit bar or tablet of soap with no covering 4 Requirements 4.1 General 4.1.1 Liquid toilet soap shall be in a clear and uniform aqueous solution, which may be coloured. It shall not contain non-aqueous solvents or other foreign material, and solids shall not precipitate from it during storage at ambient temperature. 4.1.2 Liquid toilet soap shall not be irritating to normal skin and it shall not contain ingredients in quantities that are toxic to human beings. It shall lather freely and quickly in water at ambient temperature, that has a hardness (expressed as calcium carbonate) of 200 × 10-6. 4.2 Odour 4.2.1 Liquid toilet soap, unless otherwise specified by the purchaser shall be perfumed and, both as received and when diluted in hot water, shall possess a pleasant odour. 4.2.2 It shall not develop an objectionable odour during storage at ambient temperature, and when perfumed its fragrance shall not change. 4.3 Consistency Liquid toilet soap, after being cooled to 4.5 °C ± 0.5 °C for 48 h shall remain liquid, and after stan ding undisturbed at ambient temperature for a further 24 h, any separation shall have disappeared. 4.4 Chemical requirements The chemical requirements of liquid toilet soap shall, when tested in accordance with the relevant tests in column 3 of Table 1, comply with the requirements given in column 2 of Table 1. 4.5 Viscosity at 25 °C The viscosity of the liquid toilet soap as received, determined in accordance with 6.9 at 25 °C, shall not be more than 1 Pa.s.

Table 1 — Chemical requirements

1 2 3 Property Requirements Test method

sub-clause Free alk ali content a (as potassium hydroxide), mass fraction, %, max. 0,05

or 6.3 Free acid contenta (as oleic acid), mass fraction, %, max. 0,2 Unsaponified plus unsaponifiable matter content a , mass fraction, %, max. 1,0 6.4 Alcohol insoluble matter content a, mass fraction, %, max. 0,2 6.5 Fatty matter contentb, mass fraction, %, min. 15,0 6.6 Chloride content a (as potassium chloride), mass fraction, %, max. 0,3 6.7 Rosin content of fatty matter, mass fraction, %, ma x. 4,0 6.8 a Corrected to a fatty matter content mass fraction of 15 %. b On the soap as received.

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© EAC 2010 — All rights reserved 3

5 Sampling and compliance with this standard 5.1 Sampling 5.1.1 General When no information concerning the implementation of quality control or testing during manufacture is available, the following sampling procedure shall be applied to determine whether a lot submitted for inspection and testing complies with the requirements of the standard. The samples so taken shall be deemed to represent the lot for the respective properties. The sampling procedure shall also be used for adjudication in cases of dispute. 5.1.2 Sample for inspection Draw at random from the lot a) five containers if the lot is packed in containers of net volume not exceeding 5 L, and b) three containers if the lot is packed in containers of net volume greater than 5 L. 5.1.3 Sample for testing 5.1.3.1 From the containers taken in accordance with 5.1.2, take at random enough soap to provide a laboratory sample of total volume at least 1 L (take equal quantities of soap from all containers). 5.1.3.2 Before drawing a sample, thoroughly mix the contents of the container. 5.1.3.3 Pour the laboratory sample in clean, dry, air-tight glass or plastics containers clearly marked with the manufacturer's name or trade mark, the batch identification, and the date of sampling. 5.2 Compliance with this standard Deem the lot to comply with the requirements of the standard if, after inspection and testing of the samples taken in accordance with 5.1.2 and 5.1.3, the samples are found to comply with all the requirements of the standard. 6 Inspection and methods of test 6.1 Inspection 6.1.1 Inspect the containers (and when relevant the wrappers) taken in accordance with 5.1.2 for compliance with the requirements of Clause 7. 6.1.2 Visually examine the samples taken in accordance with 5.1.2 for compliance with the requirements given in 4.1 and 4.2. 6.2 Preparation of test specimens 6.2.1 Composite specimen Thoroughly mix the sample taken in accordance with 5.1.3 by vigorously shaking it in the original glass or plastics bottle. 6.2.2 Test specimens 6.2.2.1 Immediately after preparing the composite specimen, take at one time all the test specimens required for analysis.

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4 © EAC 2010 — All rights reserved

6.2.2.2 Weigh out the test specimen required for the determination of free alkali or free acid content last, and test it immediately. 6.2.2.3 Ensure that any pick-up or loss of moisture is reduced to a minimum by carrying out the weighing and the preparation of the test specimens as rapidly as possible. 6.3 Free alkali content or free acid content Use ISO 684 or ISO 4314. Check for compliance with Table 1. 6.4 Unsaponified plus unsaponifiable matter content Use ISO 1067. Check for compliance with Table 1. 6.5 Alcohol insoluble matter content Use ISO 673. Check for compliance with Table 1. 6.6 Fatty matter content Use ISO 685. Check for compliance with Table 1. 6.7 Chloride content Use ISO 456 or ISO 4323. Check for compliance with Table 1. 6.8 Rosin content of fatty matter Use Annex D after confirming the presence of rosin by Annex C. Check for compliance with Table 1. 6.9 Viscosity at 25 °C Use EAS 85-3. Check for compliance with Table 1. 7 Packing and marking 7.1 Packing 7.1.1 The liquid toilet soap shall be so packed as to prevent leakage and contamination of the product. 7.1.2 The liquid toilet soap shall be packed in containers that are strong enough to withstand normal usage and transportation. These containers may then be packed in bulk packages. Only soap from the same batch shall be packed together in a container and, when relevant, in a bulk package. 7.2 Marking Each container and bulk package shall bear in prominent, legible and indelible marking the information required in terms of the relevant national regulations and statutory requirements and the following additional information, as relevant:

a) the manufacturer's name or trade mark or both;

b) the words "Liquid Toilet Soap";

c) the batch identification (this may appear on containers only);

d) the volume, in litres, of the contents; and

e) in the case of bulk packages, the number of containers.

Page 9: EAST AFRICAN STANDARD - EAC QUALITY...6.2.2.2 Weigh out the test specimen required for the determination of free alkali or free acid content last, and test it immediately. 6.2.2.3

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© EAC 2010 — All rights reserved 5

Annex A

(normative)

Notes to purchasers The following requirement shall be specified in tender invitations and in each order or contract: when relevant, that the soap shall not be perfumed (see 4.2).

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6 © EAC 2010 — All rights reserved

Annex B

(normative)

Quality verification of liquid toilet soap When a purchaser requires ongoing verification of the quality of liquid toilet soap, it is suggested that, instead of concentrating solely on evaluation of the final product, he also direct his attention to the manufacturer’s quality system. In this connection it should be noted that ISO 9001 covers the provisions of an integrated quality system.

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© EAC 2010 — All rights reserved 7

Annex C

(normative)

Identification of rosin content of fatty matter in soaps C.1 Scope This Annex specifies the Halphen-Grimaldi and Liebermann-Storch method for the identification of rosin in fatty matter. C.2 Reagents NOTE Use only analytical grade reagents and distilled water. C.2.1 Acetic anhydride. C.2.2 Sulphuric acid, density 1.53 g/mL. Cautiously add 97 mL of sulphuric acid (density 1.84 g/mL) to 100 mL of water. C.2.3 Solution A. Dissolve 10 g of phenol in 27 mL of chloroform. C.2.4 Solution B. Dissolve 10 mL of bromine in 40 mL of chloroform. C.3 Procedure C.3.1 Halphen-Grimaldi method C.3.1.1 Place one or two drops of the fatty matter, reserved from the determination of fatty matter (ISO 685), in a porcelain basin and add approximately 2 mL of the solution A to dissolve it. Wet the walls of the basin by tilting and turning it and let it stand for a few seconds so that the walls of the basin are covered with a very thin film of the solution. C.3.1.2 Hold the neck of the flask containing the solution B in such a position that the bromine vapour diffuses into the porcelain dish and comes into contact with the walls. In the presence of rosin a blueish-grey to purple colour develops immediately. C.3.1.3 Carry out a comparison test with a sample of fatty matter to which 2 % (m/m) of rosin has been added. NOTE Should the colour reaction in C.3.1.2 be masked by other colours, conduct a second qualitative test, using the Liebermann-Storch method. C.3.2 Liebermann-Storch method C.3.2.1 Place 1 g - 2 g of the fatty matter in a test tube, add 5 mL - 10 mL of the acetic anhydride, and heat the mixture in a boiling water bath for approximately 3 min. Cool to room temperature and pour 1 mL - 2 mL of the solution into a white porcelain basin. C.3.2.2 Allow one or two drops of the sulphuric acid to run down the side of the basin. If rosin is present, a violet colour immediately develops where the acid is in contact with the solution. This colour then turns brown on standing. C.3.2.3 Carry out a comparison test with a sample of fatty matter to which 2 % (m/m) of rosin has been added.

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8 © EAC 2010 — All rights reserved

Annex D

(normative)

Determination of rosin content of fatty matter in s oaps D.1 Scope This Annex specifies a method for the determination of the rosin content of fatty matter in soaps. NOTE 1 Before proceeding with the quantitative determination of rosin, first establish its presence by a qualitative test (see Annex C). NOTE 2 The following method is not accurate for rosin concentrations below a mass fraction of 5 %. D.2 Reagents NOTE Use only analytical grade reagents and distilled water. D.2.1 Diethyl ether Free from peroxides. D.2.2 Sodium chloride D.2.3 Sodium sulfate Anhydrous. D.2.4 Hydrochloric acid solution Dilute one volume of concentrated hydrochloric acid (density 1.16 g/mL) with two volumes of distilled water. D.2.5 Sodium hydroxide solution 10 % mass fraction aqueous solution. D.2.6 Naphthalene-2-sulfonic acid solution Dissolve 40 g of naphthalene-2-sulfonic acid in 1 L of absolute methanol. D.2.7 Sodium chloride solution, saturated Shake an excess of sodium chloride with water at ambient temperature until no more dissolves. Keep the solution over solid sodium chloride. D.2.8 Sodium chloride solution, 10 % Dissolve 10 g of sodium chloride in 100 mL of water. D.2.9 Standard ethanolic potassium hydroxide soluti on, 0.2 N D.2.9.1 Preparation Purify 95 % (by volume fraction) ethanol by boiling 1.5 L of it over 20 g of potassium hydroxide for 1 h under reflux. Distil, discarding the first 50 mL of the distillate and stopping the distillation when approximately 1.3 L have been distilled. Dissolve 12 g of potassium hydroxide in 1 L of the purified ethanol, allow the solution to stand for approximately one week, and then decant the clear supernatant liquid from any potassium carbonate that has precipitated.

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© EAC 2010 — All rights reserved 9

D.2.9.2 Standardization Accurately weigh out approximately 1 g of potassium hydrogen phthalate (previously dried at 110 °C ± 5 °C for 3 h) into a 250 mL Erlenmeyer flask. Add a pproximately 100 mL of carbon dioxide-free distilled water and three drops to five drops of the phenolphthalein indicator, and swirl gently until the solid has dissolved. Titrate the solution with the standard ethanolic potassium hydroxide solution, until a permanent pink colour is formed. D.2.9.3 Calculation Normality of the standard ethanolic potassium hydroxide solution (N):

B

.AN

8974×=

where A is the mass of the potassium hydrogen phthalate, in grams; B is the volume of the standard ethanolic potassium hydroxide solution used for the

titration, in millilitres. D.2.10 Methyl orange indicator Dissolve 0.2 g of methyl orange in 100 mL of carbon dioxide-free water. D.2.11 Phenolphthalein indicator Dissolve 0.5 g of phenolphthalein in 100 mL of freshly boiled, 95 % (by volume fraction) ethanol. D.3 Procedure D.3.1 Preparation of fatty matter D.3.1.1 Carbolic soaps D.3.1.1.1 Weigh out accurately into a 600 mL beaker such quantity of the test sample as contains approximately 40 g of fatty matter and dissolve it in approximately 400 mL of hot water, to which 40 mL of the sodium hydroxide solution has been added. D.3.1.1.2 Salt out the soap by adding sufficient sodium chloride to the hot solution to saturate it (at ambient temperature) with sodium chloride. Filter the soap quantitatively, and allow it to drain. D.3.1.1.3 Dissolve the drained soap in approximately 400 mL of hot water, and repeat the salting out and filtering procedure. D.3.1.1.4 Wash the soap thoroughly with the saturated sodium chloride solution, and proceed in accordance with D.3.1.2.2 to D.3.1.2.7. D.3.1.1.5 Reserve the combined filtrates and washings for the determination of carbolic acids. D.3.1.2 Other soaps D.3.1.2.1 Weigh accurately into a 600 mL beaker such quantity of the test sample as contains approximately 40 g of fatty matter. D.3.1.2.2 Dissolve the soap in approximately 400 mL of hot distilled water, cool the solution, and slowly add an excess of the hydrochloric acid solution. Cover the beaker with a watch-glass and heat

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10 © EAC 2010 — All rights reserved

the contents until the fatty matter separates into a clear layer, but do not allow the temperature to exceed 60 °C. D.3.1.2.3 In the cases of liquid and gel soaps, acidify the soap as it is. D.3.1.2.4 Cool to approximately 25 °C and transfer the conten ts of the beaker to a separating funnel. Rinse the watch-glass and the beaker with portions of the diethyl ether totalling 100 mL and add them to the separating funnel. Shake the mixture in the separating funnel vigorously for 1 min, and let it stand until the two phases have separated. D.3.1.2.5 Draw off and discard the aqueous layer and wash the ether extract with 50 mL portions of the sodium chloride solution until the last washing is neutral to the methyl orange indicator. D.3.1.2.6 Filter the washed ether extract into a 250 mL beaker through a filter paper containing approximately 5 g of anhydrous sodium sulfate, and wash the separating funnel and the filter with small portions of the diethyl ether. D.3.1.2.7 Evaporate the ether extract plus washings on a warm water bath. When the residue is just dry, heat it rapidly to 130 °C and immediately plac e the beaker in a desiccator to cool. NOTE D.3.1.2.2 to D.3.1.2.7 should be completed in the shortest possible period of time, so as to prevent oxidation of the fatty acids. D.3.2 Determination of rosin content D.3.2.1 Weigh accurately into a 150 mL flask with a ground-glass joint approximately 2 g of the prepared fatty matter (D.3.1.2.7) and reserve the rest in the case of soap powders for the fatty matter titre determination. D.3.2.2 Add exactly 25 mL of the naphthalene-2-sulfonic acid solution to the flask and two or three glass beads, and boil under reflux for 30 min. D.3.2.3 Carry out a blank test at the same time, using exactly 25 mL of the naphthalene-2-sulfonic acid solution only. D.3.2.4 Cool the contents of both flasks (sample and blank) to ambient temperature, add 0.5 mL of the phenolphthalein indicator to each flask, and immediately titrate to the end point with the standard ethanolic potassium hydroxide solution. D.4 Calculation Rosin content of fatty matter, as a mass fraction percentage (R):

01634

.C

.N)BA(R −××−=

where A is the volume of the standard ethanolic potassium hydroxide solution used for the

titration of the sample solution, in millilitres; B is the volume of the standard ethanolic potassium hydroxide solution used for the

titration of the blank solution, in millilitres; N is the normality of the standard ethanolic potassium hydroxide solution; C is the mass of the fatty matter taken, in grams.

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© EAC 2010 — All rights reserved 11

Annex E

(normative)

Water insoluble matter content of soap products E.1 Scope This standard specifies a method for the determination of the water insoluble matter content of soap products. E.2 Apparatus E.2.1 Oven . A drying oven capable of being maintained at 105 ± 5 °C. E.3 Procedure E.3.1 Soap powders, gel soaps Thoroughly wash the residue on the glass fibre filter, retained from the determination of free alkali content and free acid content, with hot distilled water. Dry the residue and the filter in the oven maintained at 105 ± 5 °C, cool in a desiccator, and weigh. E.3.2 Scouring compounds Dry the residue and the filter, retained from the determination of alkaline salts, in the oven maintained at 105 ± 5 °C, cool in a desiccator, and weigh. Rep eat the drying and weighing procedure until no further loss in mass occurs. E.4 Calculation E.4.1 Soap powders, gel soaps

Water insoluble matter content, NB

MA

×××= 100

%(m/m)

where A = mass of the residue, g B = mass of the test sample used, g M = required minimum fatty matter content of the sample, % N = actual fatty matter content of the sample, %. E.4.2 Scouring compounds

Water insoluble matter content, B

A 100×=%(m/m)

where A = mass of the residue, g B = mass of the test sample used, g.

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© EAC 2010 — All rights reserved