Bitumen and bituminous binders - Development of performance-related specifications: status report 2005

TC 336/WG 1 has agreed to produce a Technical Report (CEN-TR) to summarise and illustrate the ongoing work in the standardisation area with reference to the process of developing from traditional "empirical" based specifications to new "performance-related" specifications for paving bitumens, as required by the Mandate M/124. It was decided that it would be better to maintain such a report as an ‘informative’ document, which can be regularly amended and updated by TC 336/WG 1 as appropriate.

Bitumen und bitumenhaltige Bindemittel - Entwicklung von auf das Gebrauchsverhalten bezogenen Spezifikationen: Statusbericht 2005

TC 336 WG 1 hat beschlossen, einen Technischen Bericht (CEN-TR) zu erstellen, um die laufende Arbeit im
Bereich der Normung in Bezug auf den Entwicklungsprozess von traditionellen „empirisch“ basierten Spezifi-kationen
hin zu neuen „gebrauchstauglichkeitsbezogenen“ Spezifikationen für Straßenbaubitumen, wie sie
nach dem Mandat M/124 gefordert sind, zusammenzufassen und zu erläutern. Es wurde entschieden, dass
es besser sei, einen derartigen Bericht als ,informatives‘ Dokument zu behandeln, das von TC 336/WG 1 je
nach Bedarf in regelmäßigen Abständen geändert und aktualisiert werden kann.

Bitumes et liants bitumineux - Elaboration de spécifications reliées aux performances : rapport d'avancement 2005

Le TC 336/WG 1 a donné son accord pour produire un rapport technique (CEN-TR) visant a récapituler et a illustrer les travaux de normalisation en cours qui concernent le processus de transformation des spécifications traditionnelles « empiriques » en nouvelles spécifications « reliées aux performances » portant sur les bitumes routiers, selon les exigences du mandat M/124. Il a été décidé de laisser a ce rapport sa nature de document informatif, pouvant etre régulierement amendé et mis a jour par le TC 336/WG 1 en fonction des besoins.

Bitumen in bitumenska veziva – Razvoj specifikacij za lastnosti, ki so povezane z obnašanjem: poročilo o statusu 2005

General Information

Status
Withdrawn
Publication Date
31-Aug-2006
Withdrawal Date
19-Nov-2020
Technical Committee
Current Stage
9900 - Withdrawal (Adopted Project)
Start Date
20-Nov-2020
Due Date
13-Dec-2020
Completion Date
20-Nov-2020

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SLOVENSKI STANDARD
SIST-TP CEN/TR 15352:2006
01-september-2006
%LWXPHQLQELWXPHQVNDYH]LYD±5D]YRMVSHFLILNDFLM]DODVWQRVWLNLVRSRYH]DQH]
REQDãDQMHPSRURþLORRVWDWXVX
Bitumen and bituminous binders - Development of performance-related specifications:
status report 2005
Bitumen und bitumenhaltige Bindemittel - Entwicklung von auf das Gebrauchsverhalten
bezogenen Spezifikationen: Statusbericht 2005
Bitumes et liants bitumineux - Elaboration de spécifications reliées aux performances :
rapport d'avancement 2005
Ta slovenski standard je istoveten z: CEN/TR 15352:2006
ICS:
75.140
91.100.50
SIST-TP CEN/TR 15352:2006 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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TECHNICAL REPORT
CEN/TR 15352
RAPPORT TECHNIQUE
TECHNISCHER BERICHT
April 2006
ICS 75.140; 91.100.50

English Version
Bitumen and bituminous binders - Development of performance-
related specifications: status report 2005
Bitumes et liants bitumineux - Elaboration de spécifications Bitumen und bitumenhaltige Bindemittel - Entwicklung von
axées sur les performances : rapport d'avancement 2005 auf das Gebrauchsverhalten bezogenen Spezifikationen:
Statusbericht 2005
This Technical Report was approved by CEN on 27 November 2005. It has been drawn up by the Technical Committee CEN/TC 336.
CEN members are the national standards bodies of Austria, Belgium, 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
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2006 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TR 15352:2006: E
worldwide for CEN national Members.

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CEN/TR 15352:2006 (E)
Contents Page
Foreword .3
1 Executive summary.4
2 Scope of the report .5
3 Introduction.5
4 Motivation and expected benefits.5
5 From pavement perfomanced requirements to binder properties .6
6 Preliminary phase (1999 – 2003) .6
7 Detailed review of binder properties and their potentially associated test methods .7
7.1 General.7
7.2 Elevated service temperature property .8
7.3 Intermediate service temperature property.9
7.4 Low service temperature property.10
7.5 Durability (or ageing simulation / conditioning) .11
7.6 Fatigue.13
7.7 Cohesion.13
7.8 Adhesion.13
7.9 Other properties.13
8 Validation of test methods .14
8.1 General.14
8.2 BiTVal Project.14
8.3 Data Collection.15

9 Summary and conclusion - Development of P- R specifications .16
Annex A First generation specifications.18
Annex B EAPA binder evaluation.22
Annex C Detailed review of binder properties and associated test methods .24
C.1 TASK GROUP 1 - Elevated service temperature property .24
C.2 TASK GROUP 2 - Low service temperature property.26
C.3 TASK GROUP 3 - Durability (or ageing simulation / conditioning) .29
Annex D FEHRL validation project.33
D.1 Introduction.33
D.2 Project methodology.33
D.3 Project organisation.34
D.4 Project timetable.35
D.5 Outputs.35
Annex E  Data collection framework – Version 2005 .37
Annex F GLOSSARY.39
F.1 Organisations.39
F.2 Equipment, test methods and associated parameters.39
F.3 Product related acronyms.40
F.4 Standardisation acronyms.40

2

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CEN/TR 15352:2006 (E)
Foreword
This Technical Report (CEN/TR 15352:2006) has been prepared by Technical Committee CEN/TC 336
“Bituminous binders”, the secretariat of which is held by AFNOR.
3

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CEN/TR 15352:2006 (E)
1 Executive summary
This Technical Report contains a synthesis of TC 336/WG 1 work on the development of second generation
(performance-related) specifications for paving grade bitumens. It is a CEN Technical Report (TR) and will be
regularly updated by TC 336.
TC 336 Working Groups are completing their work to produce ‘harmonised’ first generation European
specifications and test methods for paving bitumens, including EN 12591 (paving grades), prEN 13924 (hard
grades) and EN 14023 (PMB). These are based on existing (empirical) national standards.
A process, involving industry-wide participation, is being followed to ensure that, for the second generation
standards, the performance relationships of a binder property are assessed before a specification is
developed. The basic sequential steps are as follows:
• Step 1: identify the binder properties linked to the performance requirements of asphalt pavements,
• Step 2: select and standardise appropriate (new) test methods to measure these properties,
• Step 3: collect data and ensure field validation for establishing (new) binder specifications,
• Step 4: review the grading system according to the (new) specification.
The development work has reached Step 3. Although new tests methods, when identified, could still be added,
the main thrust currently is on validation of the test methods selected by WG 1. There are two major tasks
being undertaken;
 Literature review.
A project, named “BiTVal”, is being undertaken by FEHRL. The first phase of the project is to
evaluate the published literature on relationships between bitumen characteristics and
asphalt/pavement behaviour. A FEHRL report will make recommendations on use of binder tests by
WG 1, and also identify gaps in the knowledge.
 Collection of data for existing bitumens using the selected test methods.
This CEN/TR contains a framework of properties and test methods, which is being used as the basis
for data collection. The intention is to encourage widespread input from member states and the
industry around Europe. As confidence in the validation of the (new) test methods is established it
may be decided to introduce them progressively into the existing specifications according to priority
of need.
It is, of course, recognised that the binder properties alone do not determine pavement performance. Other
parameters, such as aggregate characteristics, mix design, manufacture and laying are also considered as
important. Nevertheless the goal of the work of WG 1 is to propose a framework, which could include levels or
classes, and which can be used in new performance-related specifications for paving grade binders.
The TC 336 business plan recognises that the development of new P-R specifications will be a long-term
process. This Technical Report will be a living document, being regularly updated, to indicate the current state
of progress of the work of WG 1.
4

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CEN/TR 15352:2006 (E)
2 Scope of the report
TC 336/WG 1 has agreed to produce a Technical Report (CEN-TR) to summarise and illustrate the ongoing work
in the standardisation area with reference to the process of developing from traditional “empirical” based
specifications to new “performance-related” specifications for paving bitumens, as required by the Mandate
M/124. It was decided that it would be better to maintain such a report as an ‘informative’ document, which can
be regularly amended and updated by TC 336/WG 1 as appropriate.
3 Introduction
The European Committee for Standardization (CEN) was formed in the early sixties and was charged with
preparing common rules and standards to be used in all member countries to ensure no barriers to trade.
As part of that programme, new harmonised European specifications for paving grade bitumens are being
developed in two stages:
a) First generation (CEN/TC 19/SC 1, since 1990) – The working groups have completed their work to
produce specifications and test methods for paving bitumens, for use throughout Europe, which were
based on existing national standards. Such specifications (already published in 1999 as EN 12591, and
now under revision after 5 years in use) are well known as empirical tests based specifications.
The first generation standards, including EN 12591, EN 13924 (hard grades) and EN 14023 (PMB), and
their associated test methods, are summarised in Annex A.
b) Second generation (CEN/TC 336, since 2000) – The next task of the working groups is to produce
specifications that are more Performance-Related, to reflect the binder contribution to the performance of
the asphalt pavement, with the inclusion of existing or new properties and test methods, as appropriate.
Bitumen specifications have remained relatively unchanged over the last forty years and the specifications now
being developed represent a very significant step forward for all involved contributors such as producers, asphalt
suppliers, contractors and administrations all over Europe.
4 Motivation and expected benefits
In the EC’s acceptance of the CEN/TC 336 response to the Mandate, it was stated:
”The Commission understand that the standards, which will be developed, are the generation of empirical
specifications. CEN/TC 336 is encouraged to develop new specifications, performance-related, as soon as
possible, after finalisation of the first generation standards. If TC 336 considers there is a need to change
some of the performance characteristics for the second generation of standards, in line with a performance
based approach, a revision of the mandate should be proposed by CEN/TC 336 to the Commission.”
The second generation of standards can be more ‘market-driven’. The aim is good quality asphalt roads that
perform well throughout their lifetime. Specifications and standards should meet both the technical and commercial
needs of the asphalt industry and its customers, and it is important these needs are properly identified and
understood.
The overall purpose of the specification system will be to ensure that binders can be evaluated on a fair and
comparable basis, that the appropriate binder can easily be selected for a particular application and that the binder
can be used with confidence in its quality. Ideally, the system should be suitable throughout Europe, for all types of
climatic and traffic conditions, for a large variety of pavement applications, and applicable to all categories of
binders: conventional, special and modified bitumens.
5

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CEN/TR 15352:2006 (E)
5 From pavement perfomanced requirements to binder properties
It is important that the market needs are correctly identified and addressed, therefore the involvement of key
stakeholders has been sought: road owners and authorities, specifiers, road contractors, asphalt and binder
producers. A good and effective communication between all these players was necessary for a satisfactory
development of the WG 1 programme.
It is, of course, recognised that the binder properties alone do not determine pavement performance. Other
parameters, such as aggregate characteristics, mix design, manufacture and laying are also considered as
important. A process is being followed to ensure that, for the second generation standards, the performance
relationships of a binder property are assessed before a specification is developed. The basic sequential
steps are as follows:
• Step 1: identify the binder properties linked to the performance requirements of asphalt pavements,
• : select and standardise appropriate (new) test methods to measure these properties,
Step 2
• Step 3: collect data and ensure field validation for establishing (new) binder specifications,
• Step 4: review the grading system according to the (new) specification.
6 Preliminary phase (1999 – 2003)
In order to take a systematic approach to second generation binder specifications the European bitumen/asphalt
industry has made major efforts in recent years to define the “performance-related” requirements for paving
binders.
In 1999, Eurobitume organised a workshop with global attendance representing all sides of the asphalt industry,
and delegates collectively identified the principle performance requirements of asphalt pavements and then
related these to the appropriate binder properties and thence to the possible tests required to measure these
properties. Figure 1 summarises the outcome from that workshop, and the starting point for much of the work
since.

Figure 1 — EUROBITUME - Industry Workshop, Luxemburg, 1999
6

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CEN/TR 15352:2006 (E)
In 2000, CEN/TC 336 was established and the ‘new’ WG 1 started work on development of a new
performance-related specification for paving binders. This includes PMBs as well as unmodified binders, and
so amalgamates the work of the old WG 1 and WG 4.
Working Group 1 decided from the beginning to establish Task Groups to work on the three key properties that
were identified at Workshop ’99, as essential parts of any new specifications for paving binders:
• high (service) temperature properties (TG 1),
• low (service) temperature properties (TG 2), and
• ageing and conditioning (TG 3).
For these topics there was considerable existing background information and test methods from the US,
particularly from the SHRP project developments. These were taken into account together with published
development work from around the world.
Other properties and test methods have been subsequently added to the list in an ongoing process to address
the identified performance requirements, in particular:
• adhesion;
• cohesion;
• fatigue.
In parallel with the above, there have been two major exercises to update and refresh the thinking on the
outcomes of the Workshop 99.
i) BiTSpec project
In 2002/03, a series of regional seminars, supported by Eurobitume and the European Asphalt Pavement
Association (EAPA), were held around Europe, on the subject of “Bituminous Binder Testing and
Specifications”, culminating in the BiTSpec Seminar in Brussels, in June 2003. The seminars were well
attended by representatives from all parts of the industry, and the outputs from that project were made
available to WG 1, ref. Eurobitume BiTSpec Proceedings, 2003.
ii) TC 336 Advisory Group
CEN/TC 336 Advisory Group (which is constituted by the five key European road industry stakeholder groups)
also provided a comprehensive report in 2003 on the subject of “Binder requirements”, compiled from
individual position papers from the Eurobitume, EAPA, FEHRL, WERD (now renamed CERD), IISRP. The
final report is being used by WG 1, ref. TC 336/AG N9, 2003.
7 Detailed review of binder properties and their potentially associated test methods
7.1 General
The input from EAPA on the needs for asphalt pavement performance is summarised in the form of the table
shown in Annex B. This is considered as fundamental input to the work of TC 336/WG 1/TG 5. For each binder
property, WG 1 has considered the possible/available test methods, see below. Test method selection is an
ongoing part of the work of the working groups. At this stage, it is important to maintain an "open door" to new
ideas and suggestions. Therefore CEN/TC 336 will continue to monitor development elsewhere, particularly in
the USA (SuperPave) and to select relevant options for evaluation. In particular, new proposals can be expected
from work in:
 US binder research programmes,
7

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CEN/TR 15352:2006 (E)
 CEN Ad-Hoc Group adhesion/durability (TC 336/TC 227), and
 RILEM.
The current status of evaluation of test methods by WG 1 is summarised in this chapter, and in more detail in
Annex C.
At this stage, several test methods have been harmonized for some properties in order to gain experience
with their use before selecting the most appropriate one.
7.2 Elevated service temperature property
Several tests are available for measuring viscosity/rheology at different temperatures, including the "high road
service temperature" range.
Seven test methods have been evaluated by TG 1:
softening point, vacuum capillary, dynamic viscosity, complex modulus DSR, Low/Zero Shear

Viscosity ZSV (oscillation & creep modes), Australian viscosity.
7.2.1 Current status of standardisation
Table 1 shows a summary of the status of WG 1 evaluation and standardisation of the test methods; for more
details see Annex C.
8

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CEN/TR 15352:2006 (E)
Table 1 — Elevated service temperature test methods
Status EN
Test method Reference Comments
Standardisation
Softening point YES EN 1427 Under revision, following
the 5-year review in
2004
Vacuum capillary YES EN 12596 Under revision, following
the 5-year review in
2004
Dynamic viscosity YES EN 13702 Part 1: published, 2003
Part 2: published, 2004
Complex Modulus YES EN 14770 Published, 2005
using DSR
Low Shear Viscosity YES prEN 15324 Standing for CEN
LSV  enquiry, 2005
(oscillation mode)
Zero Shear Viscosity YES prEN 15325 Standing for CEN
ZSV (creep mode) enquiry, 2005
Australian viscosity NO - Not selected for
harmonisation

7.2.2 Further work required
Following publication of the DSR method, work is required to confirm / validate appropriate parameters from
the test.
For the new tests for Zero Shear Viscosity, further work is required to establish a correlation with road
performance.
7.3 Intermediate service temperature property
The penetration test is currently used to assess binder properties at intermediate temperatures (typically 25 °C).
The measurement of complex modulus at various temperatures is also available, e.g. via the DSR (EN 14770)
and could be related to the ‘structural strength’ in practice.
Measurements of stiffness can be made on the asphalt mixture itself using EN 12697-23 & 26: Structural
Strength and Stiffness.
9

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CEN/TR 15352:2006 (E)
7.4 Low service temperature property
Several tests are available for measuring low temperature properties of paving bitumens; six have been
evaluated by TG 2:
 Fraass breaking point, low temperature penetration, force ductility and tensile test, Bending
Beam Rheometer (BBR), complex modulus, Direct Tension Test (DTT),
 one new test is now being evaluated: Fracture Toughness Test. This test may also be
appropriate to evaluate other characteristics such as resistance of the binder to crack
propagation due to fatigue stress.
7.4.1 Current status of standardisation
Table 2 shows a summary of the status of WG 1 evaluation and standardisation of the test methods; for more
details see Annex C.
Table 2 — Low service temperature test methods
Status EN
Test method Reference Comments
Standardisation
Fraass breaking YES EN 12593 Under revision, following
point the 5-year review in
2004
Low temperature YES EN 1426 Under revision, following
penetration the 5-year review in
2004
Force Ductility and YES EN 13589 Published, 2003
Tensile Test EN 13587
Bending Beam
Rheometer YES EN 14771 Published in, 2005
(BBR)
Complex Modulus YES EN 14770 Published, 2005
using DSR
Direct Tension Test NO - No decision made yet
(DTT)
Fracture Toughness NO - Evaluation commencing

7.4.2 Further work required
The Fraass test has been used in some countries to assess low temperature properties. However there is
concern about the repeatability/reproducibility and P-R aspects of the test and it was always intended to seek an
improved low temperature test (ref. EN 12591:1999, Annex C3).
10

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CEN/TR 15352:2006 (E)
The BBR is in process of standardisation and shows promise for use in P-R specifications in future. PMBs do not
necessarily have the same critical stiffness as unmodified binders.
In the US a combination of BBR and DTT values have been proposed for specification purposes. The DTT has
not yet been standardised as an EN; the precision of the method and correlation with binder performance need
further study.
It is also possible that BBR data could be combined with data from existing EN tests such as Tensile Test or
Force Ductility test.
7.5 Durability (or ageing simulation / conditioning)
Durability is a key requirement of the asphalt/pavement. To be assessed, it requires the identification of a
minimum level of properties at the beginning of the service life (after asphalt mixing, laying and compaction) and
the retention of such “initial” performance properties to a sufficient level to ensure the design life of the road is
achieved. The binder itself has a part to play, and standards are being developed to “condition” the binder in the
laboratory to equate to its condition in the road over time.
The procedures are used for two purposes:
• pre-treatment: to prepare a binder sample for further testing, in the condition
expected in practice,
• binder evaluation: to compare the resistance to hardening.
The procedures cover two types of conditioning:
a) Short-Term (construction) ageing
[Related to changes during asphalt mixing /delivery /laying].
Four procedures have been evaluated by TG 3:
 Rolling Thin Film Oven Test (RTFOT),
 Thin Film Oven Test (TFOT),
 Rotating Flask Test (RFT), and
 Modified RTFOT.
b) Long-Term (in-service) Ageing
[Related to additional changes in the pavement during use. Tests are normally carried out on short-term aged
binder]
Four procedures have been evaluated by TG 3:
 Pressure Ageing Vessel (PAV),
 High Pressure Ageing Test (HiPAT),
 Rotating Cylinder Ageing Test (RCAT), and
 Long-Term Rotating Flask Test (LTRFT).
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CEN/TR 15352:2006 (E)
7.5.1 Current status of standardisation
Table 3 shows a summary of the status of WG 1 evaluation and standardisation of the test methods; for more
details see Annex C.
Table 3 — Bitumen ageing conditioning test methods
Status EN
Test method Reference Comments
standardisation
Short-Term Ageing
RTFOT YES EN 12607 – 1
All are existing ENs.
TFOT YES EN 12607 – 2 Work is in progress to
replace RFT by RTFOT
RFT YES EN 12607 – 3
Modified RTFOT NO - Await any new
developments
Long-Term Ageing
PAV YES EN 14679 Published in 2005
HiPAT YES “ Covered by PAV
standard
RCAT YES prEN 15323 Standing for CEN
enquiry, 2005
LT RFT NO - Development work
shelved

7.5.2 Further work required
Short-term ageing tests are available (RTFOT, TFOT, RFT) as used in EN 12591. It is intended to phase out the
use of RFT (in favour of RTFOT) in future standards for paving grade bitumens (for bitumens from EN 12591
Table 1 and Table 2).
Long Term ageing/conditioning methods are under development, and have not yet been used in specifications in
Europe. The PAV was adopted from the US "Superpave" work and is now being harmonised as EN 14769.
The RCAT has produced promising results in a mini-round robin study. More widespread use of the new
methods is required and work on precision of the procedures.
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CEN/TR 15352:2006 (E)
7.6 Fatigue
Binder fatigue behaviour is recognised as potentially an important contributor to performance, but cannot be
seen independent of the asphalt mix and pavement design. Work on binder fatigue testing is in the research
stage.
7.7 Cohesion
Bitumens normally exhibit good cohesive properties.
The measurement of cohesion is possible using three test methods developed by WG4.
The Force Ductility test (long loading time) and Tensile test (shorter loading time) are used on binders for asphalt
mixtures, and the Vialit Pendulum (impact) test can be used on binders for surface treatments.
7.8 Adhesion
No tests of adhesion are available at the moment. The performance is very dependent on the chemical and
physical nature of the surfaces to be adhered.
A joint ad-hoc group (TC 227/TC 336) is studying potential test methods.
7.9 Other properties
� Speciality properties
For special applications of asphalt, additional characteristics are important and specific test methods may be
required. Where possible the testing is carried out on the asphalt mixture, e. g.:
asphalt for use in applications where spillages of specific fuels or chemicals can occur, such as in airfield surfacing:
 EN 12697-41: Resistance to de-icing fluids,
 EN 12697-43: Resistance to fuel
� HSE related properties
It is expected that characteristics related to Health, Safety & Environmental aspects of performance would be
covered in the suppliers’ Safety Data Sheets (SDS) for the binder and need not be duplicated here in the product
standard.
The SDS should contain information under several fixed headings, including:
• composition/information on ingredients: e.g. EINECS numbers of substances present;
• hazards identification:
 human health hazards (e.g. related to handling and emissions during application);
 physical & chemical hazards (fire and handling information);
 specific hazards (e.g. information about presence of PAHs, etc…);
• physical and chemical properties: e.g. flashpoint, flammability, solubility, etc…;
• toxicology: inhalation, skin contact, etc…;
• ecological information: environmental effects, bio-degradability, leaching;
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CEN/TR 15352:2006 (E)
• recyclability (including recycling option);
• classification and labelling.
� Constancy of quality
A further con
...

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