EN ISO 7971-1:2009

Cereals - Determination of bulk density, called mass per hectolitre - Part 1: Reference method (ISO 7971-1:2009)

ISO 7971-1:2009 specifies the reference method for the determination of bulk density, called “mass per hectolitre”, of cereals as grain.

Getreide - Bestimmung der Schüttdichte, sogenannte Masse je Hektoliter - Teil 1: Referenzverfahren (ISO 7971-1:2009)

Dieser Teil von ISO 7971 legt das Referenzverfahren zur Bestimmung der Schüttdichte, der sogenannten „Masse je Hektoliter“, von Getreidekörnern fest.
ANMERKUNG   In verschiedenen Ländern werden unterschiedliche Routineverfahren angewendet. Ein Routinever¬fahren zur Bestimmung der Schüttdichte, der sogenannten „Masse je Hektoliter“, ist in ISO 7971 3 angegeben.

Céréales - Détermination de la masse volumique, dite masse à l'hectolitre - Partie 1: Méthode de référence (ISO 7971-1:2009)

L'ISO 7971-1:2009 spécifie la méthode de référence de détermination de la masse volumique, dite «masse à l'hectolitre», des céréales en grain.

Žita - Določanje prostorninske mase, imenovane hektolitrska masa - 1. del: Referenčna metoda (ISO 7971-1:2009)

General Information

• Status: Published
• Publication Date: 14-Aug-2009
• Withdrawal Date: 27-Feb-2010
• ICS: 67.060 - Cereals, pulses and derived products
• Technical Committee: CEN/TC 338 - Cereal and cereal products
• Drafting Committee: CEN/TC 338/WG 7 - Mass per hectolitre
• Current Stage: 6060 - Definitive text made available (DAV) - Publishing
• Start Date: 15-Aug-2009
• Due Date: 07-Jul-2009
• Completion Date: 15-Aug-2009
• Ref Project: SIST EN ISO 7971-1:2009 - Cereals - Determination of bulk density, called mass per hectolitre - Part 1: Reference method (ISO 7971-1:2009)

Overview

EN ISO 7971-1:2009 - "Cereals - Determination of bulk density, called mass per hectolitre - Part 1: Reference method" (CEN adoption of ISO 7971-1:2009) specifies the reference laboratory method to measure the bulk density (mass per hectolitre) of cereals as grain. The standard defines the principle, calibrated apparatus, measurement procedure and performance requirements used to obtain traceable, repeatable bulk density results expressed in kilograms per hectolitre (kg/hl).

Key topics and technical requirements

• Definition: Bulk density (mass per hectolitre) = mass of cereal divided by the volume it occupies after pouring under defined conditions; reported in kg/hl (grain as received).
• Principle: Controlled pouring from a hopper into a 20 L measuring container, followed by weighing the contained grain.
• Apparatus: detailed components and geometry are specified - pre-filling container (nominal 24 L), filling hopper with tapered tube and distributor, 20 L measuring container, guiding collar, levelling straightedge, collecting box and chassis with verticality adjustment. Some mandatory dimensional and clearance tolerances are given for reliable results.
• Weighing requirements: Non-automatic balance compensated for empty container; maximum balance error ≤ ±0.01% of load (10–20 kgf) or weights’ errors ≤ ±0.02%.
• Calibration and adjustment: Calibration by comparison with a national/international standard instrument. Procedure requires six paired measurements (apparatus under test vs reference) using a wheat sample (recommended mass per hectolitre ≥ 80 kg/hl), specific conditioning (spread thinly in test room for ~10 h, relative humidity ≤ 60 %). Maximum permissible accuracy error ±10 g; adjust by changing distributor height if exceeded.
• Procedure controls: Straightedge motion, hopper/distributor setting, and coaxial vertical alignment are critical to ensure reproducible packing and volume.

Applications and users

EN ISO 7971-1:2009 is used where high-accuracy, traceable measurements of cereal bulk density are required:

• Grain testing laboratories and national reference labs
• Grain traders and commodity exchange quality control
• Cereal processors, millers and feed producers for inventory and process control
• Equipment manufacturers (metering/handling systems) for calibration and validation
• Research institutions studying cereal physical properties

Practical benefits include consistent grading, improved contract specification enforcement, and traceable calibration of routine instruments.

Related standards

• ISO 7971-2:2009 - method of traceability for measuring instruments
• ISO 7971-3:2009 - routine methods for bulk density
• ISO 24333 - recommended sampling for cereals (sampling not part of this method)
• OIML R 15 - referenced apparatus requirements

Using EN ISO 7971-1:2009 ensures internationally harmonized, reproducible bulk density (mass per hectolitre) measurements for cereals and supports reliable quality assessment across the grain supply chain.

Standards Content (Sample)

SLOVENSKI STANDARD
01-december-2009
äLWD'RORþDQMHSURVWRUQLQVNHPDVHLPHQRYDQHKHNWROLWUVNDPDVDGHO
5HIHUHQþQDPHWRGD,62
Cereals - Determination of bulk density, called mass per hectolitre - Part 1: Reference
method (ISO 7971-1:2009)
Getreide - Bestimmung der Schüttdichte, so genannte Masse je Hektoliter - Teil 1:
Referenzverfahren (ISO 7971-1:2009)
Céréales - Détermination de la masse volumique, dite masse à l'hectolitre - Partie 1:
Méthode de référence (ISO 7971-1:2009)
Ta slovenski standard je istoveten z: EN ISO 7971-1:2009
ICS:
67.060 äLWDVWURþQLFHLQSURL]YRGLL] Cereals, pulses and derived
QMLK products
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN ISO 7971-1
NORME EUROPÉENNE
EUROPÄISCHE NORM
August 2009
ICS 67.060
English Version
Cereals - Determination of bulk density, called mass per
hectolitre - Part 1: Reference method (ISO 7971-1:2009)
Céréales - Détermination de la masse volumique, dite Getreide - Bestimmung der Schüttdichte, sogenannte
masse à l'hectolitre - Partie 1: Méthode de référence (ISO Masse je Hektoliter - Teil 1: Referenzverfahren (ISO 7971-
7971-1:2009) 1:2009)
This European Standard was approved by CEN on 8 August 2009.

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. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the CEN Management Centre or to any CEN member.

This European Standard exists 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 Management Centre has the same status as the
official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, 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: Avenue Marnix 17, B-1000 Brussels
© 2009 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 7971-1:2009: E
worldwide for CEN national Members.

Contents Page
Foreword .3

Foreword
This document (EN ISO 7971-1:2009) has been prepared by Technical Committee CEN/TC 338 “Cereal and
cereal products”, the secretariat of which is held by AFNOR, in collaboration with Technical Committee
ISO/TC 34 "Food products".
This European Standard shall be given the status of a national standard, either by publication of an identical
text or by endorsement, at the latest by February 2010, and conflicting national standards shall be withdrawn
at the latest by February 2010.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, 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 the United Kingdom.
INTERNATIONAL ISO
STANDARD 7971-1
Second edition
2009-08-15
Cereals — Determination of bulk density,
called mass per hectolitre —
Part 1:
Reference method
Céréales — Détermination de la masse volumique, dite masse à
l'hectolitre —
Partie 1: Méthode de référence

Reference number
ISO 7971-1:2009(E)
©
ISO 2009
ISO 7971-1:2009(E)
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ii © ISO 2009 – All rights reserved

ISO 7971-1:2009(E)
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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
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.
ISO 7971 (all parts) was prepared by the European Committee for Standardization (CEN) Technical
Committee CEN/TC 338, Cereal and cereal products, in collaboration with Technical Committee ISO/TC 34,
Food products, Subcommittee SC 4, Cereals and pulses, in accordance with the Agreement on technical
cooperation between ISO and CEN (Vienna Agreement).
This second edition cancels and replaces the first edition (ISO 7971-1:2003), which has been revised to take
account of ISO 7971-2:2009.
ISO 7971 consists of the following parts, under the general title Cereals — Determination of bulk density,
called mass per hectolitre:
⎯ Part 1: Reference method
⎯ Part 2: Method of traceability for measuring instruments through reference to the international standard
instrument
⎯ Part 3: Routine method
INTERNATIONAL STANDARD ISO 7971-1:2009(E)

Cereals — Determination of bulk density, called mass
per hectolitre —
Part 1:
Reference method
1 Scope
This part of ISO 7971 specifies the reference method for the determination of bulk density, called “mass per
hectolitre”, of cereals as grain.
NOTE Several routine methods are used in different countries. A routine method for the determination of bulk density,
called “mass per hectolitre”, is given in ISO 7971-3.
2 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
2.1
bulk density
“mass per hectolitre”
〈cereals〉 ratio of the mass of a cereal to the volume it occupies after being poured into a container under well-
defined conditions
NOTE 1 Bulk density is expressed in kilograms per hectolitre of grain as received.
NOTE 2 The bulk density, as defined in this part of ISO 7971, is different from “packing density” or “intrinsic density” of
cereals.
3 Principle
A sample is poured in a controlled manner from a hopper into a 20 l container, which is then weighed.
4 Requirements for apparatus
4.1 General
[2]
The apparatus used shall comply with the following requirements, which correspond to those in OIML R 15 ,
and shall be similar to that shown in Figure 1.
ISO 7971-1:2009(E)
Dimensions in millimetres
Figure 1 — Apparatus for determining bulk density of cereals (continued)
2 © ISO 2009 – All rights reserved

ISO 7971-1:2009(E)
Key
1 filling hopper 11 shutter
2 truncated cone for guiding the flow of grain 12 frame of straightedge
3 straightedge counterweight 13 straightedge
4 guiding skirt for surplus grain 14 straightedge counterweight
5 guide by rail and rollers of the frame of the straightedge 15 height of flow
6 removable part of skirt allowing the measuring container 16 wedged base support of measuring container in filling
to be removed position
7 measuring container, volume 20 l 17 collecting box for surplus grain
8 base support of measuring container 18 distributor
9 tapered emptying tube 19 straightedge
10 guiding collar for grain flow 20 handle of wedge for base support
NOTE This figure is for information only except for the dimensions shown,
...