prEN 18056

SLOVENSKI STANDARD
01-april-2024
Kulturna dediščina - Arheološki les, prepojen z vodo - Opredelitev arheološkega
lesa, prepojenega z vodo, v podporo postopkom odločanja za njegovo ohranitev
Cultural Heritage - Waterlogged archaeological wood - Characterization of waterlogged
archaeological wood to support decision-making processes for its preservation
Charakterisierung von archäologischem Nassholz als Steuerungsinstrument
Patrimoine culturel - Bois archéologique gorgé d’eau - Caractérisation du bois
archéologique gorgé d’eau dans le but de soutenir les processus de prise de décision
concernant sa préservation
Ta slovenski standard je istoveten z: prEN 18056
ICS:
97.195 Umetniški in obrtniški izdelki. Items of art and handicrafts.
Kulturne dobrine in kulturna Cultural property and
dediščina heritage
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
EUROPEAN STANDARD
NORME EUROPÉENNE
EUROPÄISCHE NORM
January 2024
ICS 97.195
English Version
Cultural Heritage - Waterlogged archaeological wood -
Characterization of waterlogged archaeological wood to
support decision-making processes for its preservation
Charakterisierung von archäologischem Nassholz als
Steuerungsinstrument
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 346.
If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations
which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

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

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2024 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 18056:2024 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
Introduction . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Aim of characterization . 7
4.1 General . 7
4.2 Characterization for preservation by recording . 8
4.3 Characterization for in-situ preservation and controlled reburial . 8
4.4 Characterization for remedial conservation . 9
4.4.1 General . 9
4.4.2 On-site characterization . 9
4.4.3 In the laboratory . 9
5 Sampling plans for characterization . 9
6 Characterization methods .10
6.1 General .10
6.2 Wood species identification .10
6.3 Dating and tree ring analyses .10
6.4 Degradation profile .10
6.4.1 General .10
6.4.2 Physical and mechanical properties .10
6.4.3 Morphological alteration.12
6.4.4 Chemical properties .12
7 Data reporting .13
Annex A (informative)  Common techniques applied to characterization of chemical properties
of waterlogged wood .14
Bibliography .15

European foreword
This document (prEN 18056:2024) has been prepared by Technical Committee CEN/TC 346
“Conservation of Cultural Heritage”, the secretariat of which is held by UNI.
This document is currently submitted to the CEN Enquiry.

Introduction
Even if waterlogged archaeological wood appears intact or in good condition upon excavation, it can
result in an extremely unstable state caused by alteration produced by different agents. Uncontrolled
drying, or even limited exposure to an unchecked climate, may cause undesirable permanent
deformations of the wooden structure altering the integrity of the wooden object.
In waterlogged environments the microbial activity usually starts at the surface of the object and
proceeds inwards. It affects the physico-mechanical properties of the material (e.g. strength, hardness,
shrinkage and density) and the structural chemical components of the wood cells.
The application of a preservation strategy will only be successful once full knowledge of the material to
be preserved has been recorded. Characterization of the wood is essential in order to manage the finds
on the site and to identify the options for further action regarding in-situ preservation, reburial, remedial
conservation or preservation by record.

1 Scope
This document provides guidelines for the characterization of waterlogged archaeological wood to
support decision-making processes for its preservation.
This document can be applied for the management of wood discovered on waterlogged sites (e.g.
terrestrial, aquatic (marine and freshwater)), as a basis for designing controlled reburial, in-situ
preservation, post-excavation storage and conservation strategies. In the case of composite artefacts
made of wood and other materials, this document is applicable only for the wooden components. Methods
for conservation, site protection and monitoring for reburial as well as in-situ preservation are beyond
the scope of this document.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
EN 15898, Conservation of cultural heritage - Main general terms and definitions
EN 16085, Conservation of Cultural property - Methodology for sampling from materials of cultural
property - General rules
EN 16682, Conservation of cultural heritage - Methods of measurement of moisture content, or water
content, in materials constituting immovable cultural heritage
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 15898 and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp/
— IEC Electropedia: available at https://www.electropedia.org/
3.1
archaeological value
archaeological significance
combination of all the values assigned to an object from an archaeological context because of its heritage
interest to present and future generations
Note 1 to entry: It is not an intrinsic characteristic of an artefact and is the sum of the cultural and natural heritage
values that a society attributes to an artefact once its existence has been established. Significance may derive not
only from the physical presence of the heritage object, but also from its context. In cases where the object is not
recognized as having archaeological value or heritage interest, it may not be subject to long-term conservation
programmes (e.g. in situ, controlled reburial, recovery).
3.2
basic density
quotient of the mass of the oven dry wood to the water-saturated volume of wood
3.3
conservation
measures and actions aimed at safeguarding tangible cultural heritage while ensuring its accessibility to
present and future generations
Note 1 to entry: Conservation embraces preventive conservation, remedial conservation and restoration. All
measures and actions should respect the significance and the physical properties of the cultural heritage item.
3.4
controlled reburial
systematic reburial of finds at the original excavation site or at another suitable location in order to
establish the original environmental conditions under which the object was previously well preserved as
the base of a further preventive conservation strategy
3.5
degradation
result of the process of wood deterioration through physical, chemical and biological factors
3.6
hardness
material's resistance to penetration or indentation
3.7
in-situ preservation
maintaining finds in their original context whilst monitoring factors influencing degradation
3.8
moisture content
MC %
weight of water contained in the wood, expressed as a ratio to the oven-dry weight of the wood
Note 1 to entry: The maximum water content (MWC %) is a particular value of MC % that is reached when all wood
structures (cell walls and cell lumens) are filled with water.
3.9
monitoring
process of collecting and assessing data pertaining to an object, its collection or its environment over time
3.10
pin test
subjective method to assess the penetration resistance (hardness) of an artefact by manually inserting a
needle into the wood
3.11
preventive conservation
all measures and actions aimed at avoiding or minimizing future deterioration or loss
Note 1 to entry: These measures are carried out within the context or on the surroundings of a find, but more often
on a group of finds, whatever their age and condition. These measures and actions are indirect – they do not
interfere with the materials and structures of the objects. They do not modify their appearance.
3.12
relative density
specific gravity
ratio of the density of the wood to the density of a given reference material, typically water
3.13
remedial conservation
all actions directly applied to a find or a group of finds aimed at arresting current damaging processes or
reinforcing their structure
3.14
supporting capacity
ability of the wood of the archaeological find to support its own weight without breaking or crushing
during lifting or transportation
Note 1 to entry: In case of reburial, this indicates the ability of the wood to support the weight of the reburial
sediments.
4 Aim of characterization
4.1 General
The aim of characterizing waterlogged archaeological wood is to support the development of a
preservation strategy (see the flow chart in Figure 1). Wood in waterlogged environments is degraded
by a range of agents resulting in a loss of
...