1973L0405 — EN — 14.04.1982 — 001.001 — 1
This document is meant purely as a documentation tool and the institutions do not assume any liability for its contents
►B COUNCILDIRECTIVE
of22November1973
on the approximation of the laws of the Member States relating to methods of testing the biode-
gradabilityofanionicsurfactants
(73/405/EEC)
(OJ L 347, 17.12.1973, p. 53)
Amended by:
Official Journal
No page date
►M1Council Directive of 31 March 1982 (82/243/EEC) L 109 18 22.4.1982
▼B
COUNCILDIRECTIVE
of22November1973
on the approximationof the lawsofthe Member States relating to
methodsoftestingthebiodegradabilityofanionicsurfactants
(73/405/EEC)
THE COUNCIL OF THE EUROPEAN COMMUNITIES,
Having regard to the Treaty establishing the European Economic
Community, and in particular Article 100 thereof;
Having regard to the Council Directive of 22 November 1973(1) onthe
approximation of the laws of the Member States relating to detergents,and in particular Article 4 thereof;
Having regard to the proposal of the Commission;
Having regard to the Opinion of the European Parliament(
2);
Having regard to the Opinion of the Economic and Social
Committee(3);
Whereas, to enable Member States to determine the level of biodegrad-
ability of the anionic surfactant, it is advisable to employ methods oftestin g already inuse for this purpose incertainMember States;whereas, however, biodegradability must be tested by a common
method inthe even t of a dispute;
Whereas as concerns the approximation of the laws of the Member
States relating to detergents, suitable tolerances for measuring biode-gradability should be determined as provided for likewise in Article 4
of Council Directive of 22 November 1973, in order to take account of
the unreliability of testing methods which could lead to rejection deci-sions having important economic consequences and whereas a rejectiondecision must only be taken therefore if an analysis shows a level ofbiodegradability less than80%,
HAS ADOPTED THIS DIRECTIVE:
Article 1
This Directive concerns the methods of testing the biodegradability of
anionic surfactants ►M1present in detergents such as those referred
to inArticle 1 of Directive 73/404/EEC ◄.
Article 2
Pursuant to Article 4 of Directive 73/404/EEC relating to detergents,
Member States shall prohibit the placing on the market and use on theirterritory of a detergent if the biodegradability of the anionic surfactantscontained therein is less than 80% determined in accordance with oneof the following methods:
— the OECD method, published inthe OECD techn ical report of 11
June 1976 on the ‘Proposed Method for the Determination of theBiodegradability of Surfactants used in Synthetic Detergents’,
— the method in use in Germany, established by the ‘Verordnung über
die Abbaubarkeit anionischer und nichtionischer grenzflächenak-tiver Stoffe in Wasch-und Reinigungsmitteln’ of 30 January 1977,
published inthe Bundesgesetzblatt 1977, Part I, page 244, as set
out in the Regulation amending that Regulation of 18 June 1980,published inthe Bundesgesetzblatt , 1980, Part I, page 706,1973L0405 — EN — 14.04.1982 — 001.001 — 2
(1) See page 51 of this Official Journal (SIC! OJ No L 347, 17. 12. 1973, p.
51.)
(2) OJ No C 10, 5. 2. 1972, p. 29.
(3) OJ No C 89, 23. 8. 1972, p. 13.▼M1
▼M1
— the method inuse inFran ce, approved by Decree of 28 December
1977 published inthe Journal officiel de la République française of
18 January 1978, pages 514 and 515, and experimental standard T
73-260 of June 1981 published by the ‘Association française de
normalisation’ (AFNOR),
— the method in use in the United Kingdom called the ‘Porous Pot
Test’ and described in Technical Report No 70 (1978) of the WaterResearch Centre.
Article 3
Under the procedure laid down in Article 5 (2) of Directive 73/404/
EEC, the laboratory opinion on anionic surfactants shall be based onthe reference method (confirmatory test procedure) described in theAnnex to this Directive.
Article 3a
The amendments required for adapting the Annex to technical progress
shall be adopted inaccordan ce with the procedure laid downinArticle
7b of Directive 73/404/EEC.
Article 4
1. Member States shall put into force the legal, statutory and admin-
istrative measures necessary to comply with this Directive withineighteen months of its notification and shall forthwith inform theCommissionthereof.
2. Member States shall ensure that the Commission be informed of
the text of the main provisions of national law they adopt in the field
covered by this Directive.
Article 5
This Directive is addressed to the Member States.1973L0405 — EN — 14.04.1982 — 001.001 — 3
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ANNEX
DETERMINATION OF THE BIODEGRADABILITY OF ANIONIC
SURFACTANTS
Reference method(confirmatorytest)
CHAPTER 1
1.1.Definition
Anionic surface active agents in the sense of this Directive are those
surface active agents which, after passage through cationic and anionic
ion exchangers, are separated by fractional elution and determined as
methylene blue active substance (MBAS) according to the analytical
procedure described inChapter 3.
1.2.Equipmentneededformeasurement
The method of measurement employs the small activated sludge plant
showninFigure 1, an d ingreater detail inFigure 2.
The equipment consists of a storage vessel A for synthetic sewage,
dosing pump B, aeration vessel C, settling vessel D, air-lift pump E to
recycle the activated sludge, and vessel F for collecting the treated
effluent.
Vessels A and F must be of glass or suitable plastic and hold at least 24
litres. Pump B must provide a constant flow of synthetic sewage to the
aeration vessel; this vessel, during normal operation, contains three litres
of mixed liquor. A sintered aeration cube G is suspended in the vessel C
at the apex of the cone. The quantity of air blown through the aerator
should be monitored by means of a flowmeter H.
1.3.Syntheticsewage
A synthetic sewage is employed for the test.
Dissolve ineach litre of tap water:
160 mg peptone,
110 mg meat extract,
30 mg urea CO(NH2)2,
7 mg sodium chloride (NaCl),
4 mg calcium chloride (CaCl2.2H2O),
2 mg magnesium sulphate (MgSO4.7H2O),
28 mg of dipotassium hydrogenphosphate (K2HPO4)
and 20 ± 2 mg MBASThe MBAS is extracted from the product to be tested by the method
giveninChapter 2. The syn thetic sewage is freshly prepared daily.
1.4.Preparationofsamples
1.4.1. Uncompounded surfactants may be examined in the original state. The
MBAS content must be determined in order to prepare the synthetic
sewage (1.3).
1.4.2. Formulated products are analyzed for MBAS and soap content. They
must be subjected to analcoholic extractionan d separationof MBAS(see Chapter 2). The MBAS content of the extract must be known in
order to prepare the synthetic sewage.
1.5.Operationofequipment
Initially fill aeration vessel C and settling vessel D with synthetic
sewage. The height of vessel D should be so fixed that the volume
contained in aeration vessel C is three litres. Inoculation is made by
introducing 3 ml of a secondary effluent of good quality, freshly
collected from a treatment plant dealing with a predominantly domestic
sewage. The effluent must be kept under aerobic conditions in the
period between sampling and application. Then set aerator G, air lift E
and dosing device B in operation. The synthetic sewage must pass
through aerationvessel C at the rate of on e litre per hour; this gives a
meanreten tiontime of three hours.1973L0405 — EN — 14.04.1982 — 001.001 — 4
▼M1
The rate of aeration should be so regulated that the contents of vessel C
are kept constantly in suspension and the dissolved oxygen content is at
least 2 mg/l. Foaming must be prevented by appropriate means. Anti-
foaming agents which inhibit the activated sludge or contain MBAS
must not be used. Air-lift pump E must be set so that the activated
sludge from the settling vessel is continually and regularly recycled to
aerationvessel C. Sludge which has accumulated aroun d the top of aera-
tionvessel C, inthe base of settlin g vessel D, or inthe circulation
circuit must be returned to the circulation at least once each day by
brushing or some other appropriate means. When sludge fails to settle,
its density may be increased by the addition of 2 ml portions of a 5%
solutionof ferric chloride, repeated as n ecessary.
The effluent from settling vessel D is accumulated in vessel F for 24
hours, following which a sample is taken after thorough mixing. Vessel
F must thenbe carefully clean ed.
1.6.Checkingmeasuringequipment
The MBAS content (in mg/l) of the synthetic sewage is determined
immediately before use.
The MBAS content (in mg/l) of the effluent collected over 24 hours in
vessel F should be determined analytically by the same method, imme-
diately after collection; otherwise the samples must be preserved,
preferably by freezing. The concentrations must be determined to the
nearest 0·1 mg/l MBAS.
As a check onthe efficien cy of the process the chemical oxygen
demand (COD), or the dissolved organic carbon (DOC) of the glass
fibre filtered effluent accumulated in vessel F and of the filtered
synthetic sewage in vessel A is measured at least twice per week.
The reductioninCOD or DOC should level off whena roughly regular
daily MBAS biodegradation is obtained, i.e. at the end of the running-in
period showninFigure 3.
The content of dry matter of the suspended solids in the activated sludge
in the aeration tank should be determined twice a week (in g/l). If it is
more than2.5 g/l, the excess activated sludge must be discarded.
The test is performed at room temperature; this should be steady and
kept between292 an d 297 K (19-24 ºC).
1.7.Calculationofbiodegradability
The percentage degradation of MBAS must be calculated every day on
the basis of the MBAS content in mg/l of the synthetic sewage and of
the corresponding effluent accumulated in vessel F. The degradability
figures thus obtained should be presented graphically as in Figure 3.
The degradability of the MBAS should be calculated as the arithmetic
meanof the figures obtain ed over the 21 days which follow the
running-in period, during which degradation has been regular and the
operation of the plant trouble-free. In any event the duration of the
running-in period should not exceed six weeks.
The daily degradationvalues are calculated to the n earest 0·1% but the
final result is given to the nearest whole number.
In some cases it may be permissible to reduce the frequency of sampling
but at least 14 results collected over the 21 days which follow the
running-in period should be used in calculating the average.
CHAPTER 2
PRELIMINARY TREATMENT OF PRODUCTS TO BE TESTED
2.1.Preliminary notes
2.1.1.Treatment of samples
The treatment of anionic surface active agents and formulated detergents
prior to the determination of biodegradability in the confirmatory test is:
Products Treatment
Anionic surfactants None1973L0405 — EN — 14.04.1982 — 001.001 — 5
▼M1
Products Treatment
Formulated detergents Alcoholic extraction followed by separa-
tion of the anionic surfactants by ion
exchange
The purpose of the alcoholic extraction is to eliminate the insoluble and
inorganic ingredients of the commercial product which in some circum-
stances might upset the biodegradability test.
2.1.2.Ion-exchange procedure
Isolation and separation of anionic surface active agents from soap, non-
ionic and cationic surfactants is required for correct biodegradability
tests.
This is achieved by an ion-exchange technique using a macro-porous
exchange resin and suitable elutants for fractional elution. Thus soap,
anionic and non-ionic surfactants may be isolated in one procedure.
2.1.3.Analytical control
After homogenizing, the concentration of anionic surfactants in the
synthetic detergent is determined according to the MBAS analytical
procedure. The soap content is determined by a suitable analytical
method. This analysis of the products is necessary to calculate the quan-
tities required to prepare fractions for the biodegradability test.
Quantitative extraction is not necessary; however, at least 80% of the
anionic surfactants should be extracted. Usually, 90% or more is
obtained.
2.2.Principle
From an homogeneous sample (powders, dried pastes and dried liquids)
an ethanol extract is obtained which contains the surfactants, soap and
other alcohol-soluble constituents of the synthetic detergent sample.
The ethanol extract is evaporated to dryness, dissolved in an isopro-
panol/water mixture and the solution obtained is passed through a
strongly acidic cation exchange/macro-porous anion exchange combina-
tion heated to 323 K (50 ºC). This temperature is necessary to prevent
the precipitation of any fatty acids which may be present in acidic
media.
Any non-ionic surfactants remain in the effluent.
Soap fatty acids are separated by elution with ethanol containing CO2.
The anionic surfactants are then obtained as ammonium salts, by elution
with an aqueous isopropanolic solution of ammonium bicarbonate.
These ammonium salts are used for the degradation test.
Cationic surfactants which might upset the biodegradability test and the
analytical procedure, are eliminated by the cation exchanger placed
above the anion exchanger.
2.3.Chemicalsandequipment
2.3.1. Deionized water
2.3.2. Ethanol, 95% (v/v) C2H5OH
(permissible denaturant: methyl ethyl ketone or methanol)
2.3.3. Isopropanol/water mixture (50/50 v/v):
50 parts by volume isopropanol (CH3CHOH.CH3)a nd
50 parts by volume water (2.3.1)
2.3.4 Solutionof carbondioxide inethan ol (approximately 0·1% CO2): using
a delivery tube with a built-insin ter, pass carbondioxide (CO2) through
the ethanol (2.3.2) for 10 minutes. Use fresh solutions only
2.3.5. Ammonium bicarbonate solution (60/40 v/v): 0·3 mol NH4HCO3in
1 000 ml of an isopropanol/water mixture consisting of 60 parts by
volume isopropanol and 40 parts by volume water (2.3.1)
2.3.6. Cation exchanger (KAT), strongly acidic, resistant to alcohol (50-
100 mesh)
2.3.7. Anion exchanger (AAT), macro-porous, Merck Lewatit MP 7080 (70-
150 mesh) or equivalent1973L0405 — EN — 14.04.1982 — 001.001 — 6
▼M1
2.3.8. Hydrochloric acid, 10% HCl (w/w)
2.3.9. 2 000 ml round-bottomed flask with ground glass stopper and reflux
condenser
2.3.10. 90 mm diameter suctionfilter (heatable) for filter papers
2.3.11. 2 000 ml filter flask
2.3.12. Exchange columns with heating jacket and tap: inner tube 60 mm in
diameter and 450 mm in height (Figure 4)
2.3.13. Water-bath
2.3.14. Vacuum drying oven2.3.15. Thermostat2.3.16. Rotary evaporator
2.4.Preparationofextract andseparationandanionicactiveagents
2.4.1.Preparation of extract
The quantity of surfactants necessary for the biodegradation test is about
50 g MBAS.
Normally, the quantity of product to be extracted will not exceed
1 000 g, but it may be necessary to extract further quantities of sample.
For practical reasons, the quantity of product used should in most cases
be limited to 5 000 g inpreparin g extracts for the biodegradationtest.
Experience has shown that there are advantages in using a number of
small extractions rather than one large extraction. The exchanger quan-
tities specified are designed for a working capacity of 600-700 mmoles
of surfactants and soap.
2.4.2Isolation of alcohol-soluble constituents
Add 250 g of the synthetic detergent to be analyzed to 1250 ml ethanol,
heat the mixture to boiling point and reflux for one hour with stirring.
Pass the hot alcoholic solutionthrough a coarse-pored suctionfilter
heated to 323 K (50 ºC) and filter rapidly. Wash the flask and suction
filter with approximately 200 ml hot ethanol. Collect the filtrate and
filter washings in a filter flask.
Inthe case of pastes or liquid products to be an alyzed, make sure that
not more than 55 g anionic surfactant and 35 g soap are contained in the
sample. Evaporate this weighed sample to dryness. Dissolve the residue
in 2 000 ml ethanol and proceed as described above.
In case of powders of low apparent density (<300g/l) it is recommended
to increase the ethanol ratio in the relation 20: 1.
Evaporate the ethanolic filtrate to dryness, preferably by means of a
rotary evaporator. Repeat the operationif a greater quan tity of extract
is required. Dissolve the residue in5 000 ml isopropan ol/water mixture.
2.4.3.Preparation of ion-exchange columns
Cation-exchange column
Place 600 ml cation-exchange resin (2.3.6) in a 3 000 ml beaker and
cover by adding 2 000 ml hydrochloric acid (2.3.8). Allow to stand for
at least two hours, with occasional stirring. Decant the acid and transfer
the resin into the column (2.3.12) by means of deionized water. The
columnshould con taina glass wool plug. Wash the columnwith deio-
nized water at a rate of 10-30 ml/min until the eluate is free of chloride.
Displace the water with 2 000 ml isopropanol/water mixture (2.3.3) at a
rate of 10-30 ml/min. The exchange column is now ready for operation.
Anion-exchange column
Place 600 ml anion-exchange resin (2.3.7) in a 3 000 ml beaker and
cover by adding 2 000 ml deionized water. Allow the resin to swell for
at least two hours. Transfer the resin into the column by means of deio-
nized water. The column should contain a glass wool plug.
Wash the column with 0·3 M ammonium bicarbonate solution (2.3.5)
until free of chloride. This requires about 5 000 ml solution. Wash again
with 2 000 ml deionized water. Displace the water with 2 000 ml isopro-
panol/water mixture (2.3.3) at a rate of 10-30 ml/min. The exchange
column is now in the OH-form and ready for operation.1973L0405 — EN — 14.04.1982 — 001.001 — 7
▼M1
2.4.4.Ion-exchange procedure
Connect the exchange columns so that the cation-exchange column is
placed on top of the anion-exchange column. Heat the exchange
columns to 323 K (50 ºC) using thermostatic control. Heat 5 000 ml of
the solution obtained in item 2.4.2 to 333 K (60 ºC) and pass the solu-
tion through the exchanger combination at a rate of 20 ml/min. Wash
the columns with 1 000 ml hot isopropanol/water mixture (2.3.3).
To obtain the anionic surface active agents (MBAS), disconnect the
KAT column. Using 5000 ml ethanol/CO2solution(323 K; 50 ºC)
(2.3.4), elute the soap fatty acids out of the KAT column. Reject the
eluate.
Thenelute the MBAS out of the AAT columnwith 5000 ml ammon ium
bicarbonate solution (2.3.5). Evaporate the eluate to dryness on a steambath or in a rotary evaporator. The residue contains the MBAS (as
ammonium salt) and possible non-surfactant anionics which have no
detrimental effect on the biodegradation test. Add deionized water to
the residue until a definite volume is obtained and determine the
MBAS content in an aliquot as in Chapter 3. The solution is used as a
standard solution of the anionic synthetic detergents for the biodegrada-
tiontest. The solutionshould be kept at a temperature below 278 K
(5 ºC).
2.4.5.Regeneration of ion-exchange resins
The cationexchan ger is rejected after use.The anion-exchange resin is regenerated by passing an additional quan-
tity of ammonium bicarbonate solution (2.3.5) down the column at a
flow rate of approximately 10 ml/minun til the eluate is free from
anionic surfactants (methylene blue test). The (SIC! Then) pass
2 000 ml isopropanol/water mixture (2.3.3) down the anion exchanger
to wash. The anion exchanger is again ready for operation.
CHAPTER 3
DETERMINATION OF ANIONIC SURFACE ACTIVE AGENTS IN
BIODEGRADABILITY TEST
3.1.Principle
The method is based on the fact that the cationic dye methylene blue
forms blue salts with anionic surfactants which can be extracted with
chloroform. To eliminate interferences, the extraction is first effected
from alkaline solution and the extract is then shaken with acidic methy-
lene blue solution. The absorbance (SIC! absorbence) of the separated
organic phase is measured photometrically at the wavelength of
maximum absorptionof 650 n m.
3.2.Reagentsandequipment
3.2.1. Buffer solutionpH 10:
dissolve 24 g sodium bicarbonate (NaHCO
3) AR and 27 g anhydrous
sodium carbonate (Na2CO3) AR in deionized water and dilute to
1 000 ml.
3.2.2. Neutral methylene blue solution:
dissolve 0·35 g methylene blue (AR) in deionized water and dilute to
1 000 ml. Prepare the solutionat least 24 hours before use. The absorb-ence of the blank chloroform phase, measured against chloroform, must
not exceed 0.015 per 1 cm of layer thickness at 650 nm.
3.2.3. Acidic methylene blue solution:
dissolve 0·35 g methylene blue (AR) in 500 ml deionized water and mix
with 6·5 ml H
2SO4(d = 1·84 g/ml). Dilute to 1 000 ml with deionized
water. Prepare the solutionat least 24 hours before use. The absorben ce
of the blank chloroform phase, measured against chloroform, must not
exceed 0·015 per 1 cm of layer thickness at 650 nm.
3.2.4. Chloroform (Trichloromethane) (AR) freshly distilled3.2.5. Dodecyl benzene sulphonic acid methyl ester3.2.6. Ethanolic potassium hydroxide solution, KOH 0·1 M3.2.7. Ethanol pure, C
2H5OH
3.2.8. Sulphuric acid, H2SO40·5 M1973L0405 — EN — 14.04.1982 — 001.001 — 8
▼M1
3.2.9. Phenolphthalein solution:
dissolve 1 g phenolphthalein in 50 ml ethanol and add 50 ml deionized
water while stirring continuously. Filter off any precipitate obtained.
3.2.10. Methanolic hydrochloric acid: 250 ml hydrochloric acid AR and 750 ml
methanol
3.2.11. Separating funnel, 250 ml
3.2.12. Graduated flask, 50 ml
3.2.13. Graduated flask, 500 ml
3.2.14. Graduated flask, 1 000 ml
3.2.15. Round-bottomed flask with ground glass stopper and reflux condenser,
250 ml; boiling granules
3.2.16. pH meter
3.2.17. Photometer for measurements at 650 nm, with 1 to 5 cm cells
3.2.18. Qualitative grade filter paper
3.3.Procedure
The samples for analysis must not be taken through a layer of foam.
After thorough cleaning with water, the equipment used for the analysis
must be thoroughly rinsed with methanolic hydrochloric acid (3.2.10)
and then with deionized water before using.
Filter the activated sludge plant influent and effluent to be examined
immediately onsamplin g. Discard the first 100 ml of the filtrates.
Place a measured volume of the sample, neutralized if necessary, into a
250 ml separating funnel (3.2.11). The volume of sample should contain
between 20 and 150 µg of MBAS. At the lower MBAS content, up to
100 ml of sample may be used. Whenusin g less than100 ml, dilute to
100 ml with deionized water. Add to the sample 10 ml of buffer solu-
tion (3.2.1), 5 ml of neutral methylene blue solution (3.2.2) and 15 ml of
chloroform (3.2.4). Shake the mixture uniformly and not too vigorously
for one minute. After phase separation, run the chloroform layer into a
second separating funnel containing 110 ml of deionized water and 5 ml
of acidic methylene blue solution (3.2.3). Shake the mixture for one
minute. Pass the chloroform layer through a cotton-wool filter
previously cleaned and wetted with chloroform into a graduated flask
(3.2.12).
Extract the alkaline and acid solutions three times, using 10 ml of
chloroform for the second and third extractions. Filter the combined
chloroform extracts through the same cottonwool filter an d dilute to
the mark inthe 50 ml flask (3.2.12) with chloroform used for rewashin g
the cotton wool. Measure the absorbance (SIC! absorbence) of thechloroform solutionwith a photometer at 650 n m in1 to 5 cm cells
against chloroform. Run a blank determination through the whole proce-
dure.
3.4.Calibrationcurve
Prepare a calibration solution from the standard substance dodecyl
benzene sulphonic acid methyl ester (tetrapropylene type mol. wt. 340)
after saponification into the potassium salt. The MBAS is calculated as
sodium dodecyl benzene sulphonate (mol. wt. 348).
From a weighing pipette, weigh 400 to 450 mg of dodecyl benzene
sulphonic acid methyl ester (3.2.5) to the nearest 0·1 mg in a round-
bottomed flask and add 50 ml of ethanolic potassium hydroxide solution
(3.2.6) and some boiling granules. After mounting the reflux condenser,
boil for one hour. After cooling, wash the condenser and ground glass
joint with about 30 ml of ethanol, and add these washings to the
contents of the flask. Titrate the solution with sulphuric acid against
phenolphthalein until it becomes colourless. Transfer this solution to a
1 000 ml graduated flask (3.2.14), dilute to the mark with deionized
water and mix.
Part of this surfactant stock solution is then further diluted. Withdraw
25 ml, transfer to a 500 ml graduated flask (3.2.13), dilute to the mark
with deionized water and mix.
This standard solution contains E/C21/C1023
20000mg MBAS per ml, where E
is the sample weight inmg.1973L0405 — EN — 14.04.1982 — 001.001 — 9
▼M1
To establish the calibrationcurve, withdraw 1, 2, 4, 6, 8 ml each of the
standard solution and dilute each to 100 ml with deionized water. Then
proceed as stated under item 3.3 including a blank determination.
3.5.Calculationofresults
The amount of anionic surfactant (MBAS) in the sample is read from
the calibration curve (3.4). The MBAS content of the sample is given
by:
mg MBAS /C21000
V= MBAS mg/l
where V = ml volume of the sample used.
Express the results as sodium dodecyl benzene sulphonate (MW 348).
3.6.Expressionofresults
Express the results as MBAS mg/l to the nearest 0·1.1973L0405 — EN — 14.04.1982 — 001.001 — 10
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Figure 1
A. Storage vessel
B. Dosing deviceC. Aerationchamber (three litres capacity)
D. Settling vessel
E. Air-lift pumpF. CollectorG. Sintered aerator
H. Air-flow meter1973L0405 — EN — 14.04.1982 — 001.001 — 11
Figure 2
▼M11973L0405 — EN — 14.04.1982 — 001.001 — 12
Figure 3
Calculationofbiodegradability—Confirmatorytest
▼M11973L0405 — EN — 14.04.1982 — 001.001 — 13
▼M1
Figure 4
Heatedexchangecolumn
(Dimensions in millimetres)
1973L0405 — EN — 14.04.1982 — 001.001 — 14