SIST EN ISO 21945:2020

SLOVENSKI STANDARD
oSIST prEN ISO 21945:2018
01-november-2018
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,62',6
Solid biofuels - Simplified sampling method for small scale applications (ISO/DIS
21945:2018)
Biogene Festbrennstoffe - Vereinfachtes Verfahren zur Probenahme bei kleinen
Anwendungen (ISO/DIS 21945:2018)
Ta slovenski standard je istoveten z: prEN ISO 21945
ICS:
75.160.40 Biogoriva Biofuels
oSIST prEN ISO 21945:2018 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN ISO 21945:2018

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oSIST prEN ISO 21945:2018
DRAFT INTERNATIONAL STANDARD
ISO/DIS 21945
ISO/TC 238 Secretariat: SIS
Voting begins on: Voting terminates on:
2018-08-29 2018-11-21
Solid biofuels — Simplified sampling method for small
scale applications
Titre manque
ICS: 27.190; 75.160.40
THIS DOCUMENT IS A DRAFT CIRCULATED
This document is circulated as received from the committee secretariat.
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
ISO/CEN PARALLEL PROCESSING
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 21945:2018(E)
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. ISO 2018

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oSIST prEN ISO 21945:2018
ISO/DIS 21945:2018(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2018
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
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ii © ISO 2018 – All rights reserved

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oSIST prEN ISO 21945:2018
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Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols and abbreviated terms . 3
5 Principle . 3
6 Visual inspection . 4
7 Preparing sampling plan and report . 4
8 Methods for sampling . 5
8.1 General . 5
8.2 Methods for sampling stationary material . 5
8.2.1 Sampling from small packages (≤ 50 kg) . 5
8.2.2 Sampling from transport containers and lorries . 6
8.2.3 Sampling from small built-in storages . 6
8.2.4 Sampling from stockpiles and stacked material . 6
8.3 Methods for sampling moving material . 8
8.3.1 General. 8
8.3.2 Manual sampling from falling streams . 8
8.3.3 Manual sampling from conveyor belts . 9
8.3.4 Manual sampling from grabs and wheel loader buckets . 9
9 Minimum number of increments . 9
10 Minimum size of increment . 9
11 Determination of the volume of the combined sample .10
12 Equipment for manual sampling .11
12.1 General .11
12.2 Sampling container for falling-stream .11
12.3 Scoops .12
12.4 Shovels .12
12.5 Forks .13
12.6 Sample extraction using hands .13
12.7 Pipes (spears) .13
12.8 Drills (augers) .13
13 Reduction of sample size .14
14 Handling and storage of samples .15
14.1 Packaging, storing and transport of samples .15
14.2 Identification / labelling .15
15 Sampling report.15
Annex A (informative) Model sampling plan and sampling report .16
Bibliography .17
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Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take Part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www .iso
.org/iso/foreword .html.
This document was prepared by Technical Committee ISO/TC 238, Solid biofuels,
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/members .html.
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Introduction
The objective of this International Standard is to provide unambiguous and clear principles for
sampling of solid biofuels from small scale applications and storages. It is to serve as a tool to enable
efficient trading of biofuels and to enable good understanding between seller and buyer. It is also a tool
for communication with equipment manufacturers. It will also facilitate the development of sampling
plans and reporting.
This document is intended for all stakeholders.
Priority in ISO 21945 is to take a number of increments which is possible to handle at small applications
under practical aspects. In ISO 18135 the priority is to obtain a sample with a defined precision and to
calculate the minimum number of increments on basis of the corresponding precision data.
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oSIST prEN ISO 21945:2018

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oSIST prEN ISO 21945:2018
DRAFT INTERNATIONAL STANDARD ISO/DIS 21945:2018(E)
Solid biofuels — Simplified sampling method for small
scale applications
1 Scope
This document describes simplified methods for taking samples of solid biofuels in small scale
applications and storages including preparation of sampling plans and reports. The main focus is on
storages with a size of ≤ 100 t. This document is applicable to the following solid biofuels:
— fine (up to about 10 mm nominal top size) and regularly-shaped particulate materials that can be
sampled using a scoop or pipe, e.g. sawdust, olive stones and wood pellets;
— coarse or irregularly-shaped particulate materials (up to 200 mm nominal top size) that can be
sampled using a fork or shovel, e.g. wood chips, hog fuel and nut shells;
— large pieces (above 200 mm nominal top size) which are picked manually (e.g. firewood and
briquettes);
This document can also be used for other solid biofuels not listed above if the procedures described in
this document are applicable. This document specifies methods to be used, for example, when a sample
is to be tested for moisture content, ash content, calorific value, bulk density, mechanical durability,
particle size distribution, ash melting behaviour and chemical composition.
NOTE If higher precision of analytical results is needed or when in doubt if this document is applicable
ISO 18135 can be used.
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.
ISO 14780, Solid biofuels — Sample preparation
ISO 16559, Solid biofuels — Terminology, definitions and descriptions
ISO 17225-1, Solid biofuels — Fuel specifications and classes — Part 1: General requirements
ISO 17225-2, Solid biofuels — Fuel specifications and classes — Part 2: Graded wood pellets
ISO 17225-3, Solid biofuels — Fuel specifications and classes — Part 3: Graded wood briquettes
ISO 17225-4, Solid biofuels — Fuel specifications and classes — Part 4: Graded wood chips
ISO 17225-5, Solid biofuels — Fuel specifications and classes — Part 5: Graded firewood
ISO 17225-6, Solid biofuels — Fuel specifications and classes — Part 6: Graded non-woody pellets
ISO 17225-7, Solid biofuels — Fuel specifications and classes — Part 7: Graded non-woody briquettes
ISO 17225-8, Solid biofuels — Fuel specifications and classes — Part 8: Graded thermally treated and
densified biomass fuels
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 16559 apply.
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ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https: //www .iso .org/obp
— IEC Electropedia: available at http: //www .electropedia .org/
3.1
combined sample
sample consisting of all the increments taken from a lot or sub-lot
Note 1 to entry: The increments may be reduced by division before being added to the combined sample.
[SOURCE: ISO 16559, 4.52]
3.2
increment
portion of fuel extracted in a single operation of the sampling device
[SOURCE: ISO 16559, 4.122]
3.3
laboratory sample
combined sample or a sub-sample of a combined sample for use in a laboratory
[SOURCE: ISO 16559, 4.124]
3.4
lot
defined quantity of fuel for which the quality is to be determined
[SOURCE: ISO 16559,4.128, modified — Note 1 to entry has been removed.]
3.5
nominal top size
aperture size of the smallest sieve through which at least 95 % by mass of the material passes during
the determination of particle size distribution
Note 1 to entry: For selection of sieves types and aperture sizes see ISO 17827-1 and ISO 17827-2.
Note 2 to entry: For pellets the diameter is used.
[SOURCE: ISO 16559, 4.137, modified — Note 1 and 2 to entry have been added for additional
information.]
3.6
sample
quantity of material, representative of a larger quantity for which the quality is to be determined
[SOURCE: ISO 16559, 4.170, modified — Note 1 to entry has been removed.]
3.7
sub-lot
part of a lot for which a test result is required
EXAMPLE Material in a transport unit or on a particular stockpile.
[SOURCE: ISO 16559, 4.197, modified — Example has been added.]
3.8
sub-sample
portion of a sample
[SOURCE: ISO 16559, 4.198]
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4 Symbols and abbreviated terms
m is the mass of the lot or sublot [g or kg];
d is nominal top size biofuel [mm];
95%
V is minimum volume of increment [litre];
incr
V is the volume required for the foreseen analyses [litre];
req
W is the width of a sampling tool [mm].
5 Principle
The main principle of sampling is to obtain a representative sample(s) from the whole lot concerned.
Every particle in the lot or sub-lot to be represented by the sample should have an equal probability of
being included in the sample. In order to do so a sampling plan is needed. Figure 1 shows the main steps
of a sampling procedure.
Under certain circumstances (e.g. certain construction types of built in storages, silos or containers)
representative sampling might not be possible.
Figure 1 — Procedure for sampling
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6 Visual inspection
Visual inspection shall be used for the choice or verification of the classification of the solid biofuels.
Based on the sampling plan, verification or selection of the sampling equipment and the sampling method
shall also be made by visual inspection. If the lot/sub-lot consists of substantially inhomogeneous
material or if it contains impurities (such as soil or pieces of metal) this shall be stated in the sampling
report. If the biofuel type or the quality of it is diverging strongly from the one expected, the sampler
shall report without any delay to the appropriate party for further instructions.
If the particle size distribution should be analyzed the visible surface of the complete lot should be
inspected for the longest particle and its lengths shall be noted in the sampling report.
NOTE 1 It is advisable to take photographs of deviations noted during visual inspection.
NOTE 2 For documentation of oversized particles photographs are useful. Therefore a folding rule or any
other scale should be included into the photograph to enable the estimation of the particles size.
7 Preparing sampling plan and report
The sampler shall prepare the sampling plan. The sampling plan may be prepared either by using a
copy of the form presented in Annex A or by preparing his own forms or documents containing the
appropriate items selected from those shown in Annex A.
Once completed this form becomes a sampling report.
The sampling plan shall include the key elements:
a) the unique identification code of the sample;
b) the name and contact data of the sampler;
c) the date and time of sampling;
d) information required in order to identify the origin of the sample (e.g. supplier(s), location of
storage, customer, trade name);
e) the type of lot or sub-lot (e.g. pile, silo, cargo hold, storage, lorry);
f) sampling from stationary or moving material;
g) the identification number of the lot or the sub-lot;
h) the mass or volume of the sub-lot or the lot;
i) the type of biofuel (wood pellet, briquette, chips, etc.);
k) the number of increments;
l) the required mass of sample;
m) the mass of sample sent to the laboratory and number of packages if applicable;
n) the question, if the combined sample has been divided before sending to the laboratory;
o) the type of packaging of the sample sent to the laboratory (e.g. airtight container, plastic bag).
Also consider including the following items:
p) in case of sampling stationary material: location (center, bottom, etc.) from where the sample was
obtained (optional: mark sampling locations in a sketch);
q) storage information of the lot (e.g. how to reach the material, weather conditions, storage inside or
outside, covered or uncovered);
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r) the sampling technique, e.g. shoveling, cross stream cutter, sampling pipe, probe, stopped belt, etc.;
s) existence of material of other origin in the same storage or pile (incl. estimated amount if possible),
e.g. residues of a former lot of pellets in a pellet storage;
j) the approximate nominal top size;
t) any other details (e.g. visual inspection remarks).
8 Methods for sampling
8.1 General
It is difficult to take samples in a way that satisfies the principle of correct sampling, stating that all
individual parts of the lot must have an equal probability of becoming Part of the final sample. The
chance that this can be achieved when the material is stationary (for example, in a silo or stockpile, or in
a lorry) is low. It is easier when the material is moving (for example, on a conveyor belt, or being loaded
into or unloaded from transport equipment). Hence sampling from moving materials is to be preferred
wherever possible, care has to be taken that fuel parameters (physical properties) to be analyzed are
not affected.
The following general aspects of sampling shall be considered:
a) Sampling equipment has to be properly cleaned and maintained. The equipment has to be controlled
after every sampling to avoid contamination of following samples.
b) The integrity of the sampled material shall be ensured, e.g. avoiding loss or gain of moisture,
formation of fines etc. E.g. working quickly and storing the sample in an airtight container, e.g.
plastic bag or bucket., during sampling could help avoiding loss or gain of moisture.
c) All increments belonging to one combined sample have to be:
— extracted in a uniform way,
— of equal weight or volume,
— transferred to the sampling container without any contamination or loss of material.
d) If an increment or combined sample mass (volume) is too large to be handled or transported, the
mass shall be reduced according to the methods described in ISO 14780.
e) All personnel performing sampling shall be properly instructed or trained in the specific use of the
device and method.
f) All aspects of health and safety have to be considered.
8.2 Methods for sampling stationary material
8.2.1 Sampling from small packages (≤ 50 kg)
When sampling a lot consisting of individual packages, a primary increment consists of an entire or
partial package. Packages (e.g. pellet bags) shall be chosen at random from the entire lot, making sure
all packages have an equal probability of being selected. The number of selected packages shall be
chosen from Table 1 (Clause 9). Since the segregation of fines is not a problem as for stationary bulk
material, the minimum number of increments specified for sampling moving material shall be chosen.
In this case one package corresponds to one increment regardless of taking the whole package or a part
of it as increment.
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If the packages are transported on a conveyor, a lot can be defined as a certain time frame, a certain
number of packages or similar. Increments shall be chosen either systematically, randomly from defined
strata, or completely at random, from the entire lot.
If the packages are stored, it is important to ensure that packages are chosen at random from the entire
lot. It is recommended not to extract all increments from one pallet but from three pallets minimum.
In case it is necessary to minimize the number of opened pallets or when access to all pallets is difficult
or impossible the possible consequences of not respecting the principle of correct sampling shall be
stated in the sampling report.
If only a part of a package is taken as an increment, it shall be taken by using a scoop. If the amount
of fines or the share of overlong particles are to be analysed the package shall be emptied completely.
Sample division is then to be performed according to Clause 13.
8.2.2 Sampling from transport containers and lorries
It is always recommended if possible to sample when the biofuel is in motion, e.g. during loading or
unloading.
It shall always be stated in the sampling report when a sampling device cannot reach the bottom of the
container.
8.2.3 Sampling from small built-in storages
In general small built-in storages and silo storages cannot be recharged completely and it is difficult to
take increments from all parts. The increments shall be extracted from different parts of the storage if
possible, chosen according to the principle as given in Figure 2 in 8.2.4.3.
When sampling the storage, special care shall be taken to encompass the possible segregation of the
material in the room, e.g. extract increments that cover the entire direction of segregation by selecting
increments at different depths. For free flowing materials, e.g. grain like material, dry olive kernels,
pellets, etc. pipes or drills are recommended to be used. An example of a pipe (Figure 5) and handling
instructions are given in 12.7. An example of a drill (Figure 6) and handling instructions are given in 12.8.
It is always recommended if possible to sample when the biofuel is in motion, e.g. during loading or
unloading.
It may be needed to take a sample from a storage that was not completely empty before refilling or from
which a relevant share has been removed already. In this case some parameters cannot be measured
representatively for the whole lot because of segregation of fine materials.
It shall always be stated in the sampling report when a sampling device cannot reach the complete area
of the storage or its bottom, with the risk of underrepresenting a certain particle size fraction etc.
Sampling from auger or suction can only be accepted if the storage is completely emptied. This is to
avoid sampling of any segregated material.
NOTE Be aware that additional mechanical stress caused by auger or suction can influence the physical
properties of the sample.
8.2.4 Sampling from stockpiles and stacked material
8.2.4.1 General
Stockpiles shall preferentially be sampled during build-up or reclaiming as this ensures accessibility
to all parts of the lot which in turn minimizes the effect of segregating materials. Only relatively small
stockpiles may be sampled while stationary using a wheel loader.
A scoop, shovel, fork, auger, grab or pipe shall be used to extract increments.
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Sampling from an orderly stack shall be done by hand. (i.e. firewood and bagged pellets). Provisions for
personal safety shall be taken when sampling from large stacks.
8.2.4.2 Sampling from stockpiles during build up or reclaiming
Increments shall be extracted either from the working face of the stockpile, or from the bucket of a
wheel loader or grab or from a single, discrete load delivered to the stockpile before being pushed into
the main stockpile. If a conveyor is used in stacking or reclaiming, or elsewhere in the material handling
process, this is the optimal sampling point, and the methods for sampling moving material shall be used
(see 8.3).
When sampling the working face of the pile, consider the possible (rolling) segregation on the surface.
Ensure that a manual auger, shovel or scoop is inserted at right angles to the surface, and that insertion
of the auger, is spread evenly over the entire surface of the pile. No portion of the increment should be
lost during extraction of the scoop from the surface. Owing to the difficulty o
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