oSIST prEN ISO 4254-18:2020

SLOVENSKI STANDARD
01-februar-2020
Kmetijski stroji - Varnost - 18. del: Nakladalniki in stroji za prevoz krme (ISO/DIS
4254-18:2019)
Agricultural machinery - Safety - Part 18: Loader wagons and forage transport wagons
(ISO/DIS 4254-18:2019)
Landmaschinen - Sicherheit - Teil 18: Ladewagen und Häckseltransportwagen (ISO/DIS
4254-18:2019)
Matériel agricole - Sécurité - Partie 18: Titre manque (ISO/DIS 4254-18:2019)
Ta slovenski standard je istoveten z: prEN ISO 4254-18
ICS:
65.060.01 Kmetijski stroji in oprema na Agricultural machines and
splošno equipment in general
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT INTERNATIONAL STANDARD
ISO/DIS 4254-18
ISO/TC 23/SC 7 Secretariat: UNI
Voting begins on: Voting terminates on:
2019-12-05 2020-02-27
Agricultural machinery — Safety —
Part 18:
Forage loader wagons and forage transport wagons
ICS: 65.060.01
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
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STANDARDS MAY ON OCCASION HAVE TO
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POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 4254-18:2019(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 2019

ISO/DIS 4254-18:2019(E)
© ISO 2019
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 2019 – All rights reserved

ISO/DIS 4254-18:2019(E)
Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Safety requirements and/or protective/risk reduction measures for all machines .3
4.1 General . 3
4.2 Controls . 3
4.2.1 General. 3
4.2.2 Manual controls . 4
4.2.3 Remote controls (with cables or cableless) . 4
4.3 Stability in parking position . 4
4.4 Articulated drawbar . 4
4.5 Pick-up Device . 6
4.6 Feeding elements and cutting devices . 9
4.7 Conveyor .11
4.7.1 Conveyor with slats .11
4.7.2 Conveyor belts.16
4.8 Other discharge elements (i.e. push-off wagon) .16
4.8.1 General.16
4.8.2 Moving path of the push-off device.17
4.9 Access to loading space .18
4.10 Boarding means .19
4.11 Discharging .19
4.11.1 Dosage cylinders .19
4.11.2 Cross conveyor belt .20
4.12 Opening and closing of the rear discharge gate . .20
4.12.1 General.20
4.12.2 Opening .20
4.12.3 Closing . .20
4.13 Scissors gate body und loading space cover .22
4.13.1 Crushing and shearing points .22
4.13.2 Hydraulically operated scissors gate body .22
4.13.3 Mechanically operated scissors gate body .22
4.14 Mechanical power transmission .23
4.15 Silage and forage body works intended to be affixed to a carrier vehicle .23
5 Verification of safety requirements or protective measures .23
6 Information for use .23
6.1 Operator's manual .23
6.1.1 General.23
6.1.2 All machines .24
6.1.3 Push-off wagons .25
6.2 Marking .25
6.2.1 General.25
6.2.2 Safety signs .25
6.2.3 Instructional signs .25
6.3 Warning and instructions .26
Annex A (informative) List of significant hazards.27
Annex B (normative) Visibility .32
ISO/DIS 4254-18:2019(E)
Annex ZA (informative) Relationship between this European Standard and the Essential
Requirements of EU Directive 2006/42/EC amended by Directive 2009/127/EC
aimed to be covered .33
Bibliography .35
iv © ISO 2019 – All rights reserved

ISO/DIS 4254-18:2019(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.
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 23, Tractors and machinery for agriculture
and forestry, Subcommittee SC 7, Equipment for havesting and coservation.
A list of all parts in the ISO 4254 series can be found on the ISO website.
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.
ISO/DIS 4254-18:2019(E)
Introduction
The structure of safety standards in the field of machinery is as follows:
a) type-A standards (basic standards) giving basic concepts, principles for design, and general aspects
that can be applied to machinery;
b) type-B standards (generic safety standards) dealing with one or more safety aspects or one or
more types of safeguards that can be used across a wide range of machinery:
— type-B1 standards on particular safety aspects (e.g. safety distances, surface temperature, noise);
— type-B2 standards on safeguards (e.g. two-hand controls, interlocking devices, pressure-
sensitive devices, guards);
c) type-C standards (machinery safety standards) dealing with detailed safety requirements for a
particular machine or group of machines.
This document is a type-C standard as stated in ISO 12100.
The machinery concerned and the extent to which hazards, hazardous situations or hazardous events
are covered are indicated in the Scope of this part of ISO 4254. These hazards are specific to mounted,
semi-mounted and trailed bale wrappers for bales of agricultural harvesting products, including
wrappers which are combined or integrated with pick-up balers.
Significant hazards that are common to all the agricultural machines (self-propelled ride-on, mounted,
semi-mounted and trailed) are dealt with in ISO 4254-1.
When requirements of this type-C standard are different from those which are stated in type-A or
type-B standards the requirements of this type-C standard take precedence over the requirements of
the other standards for machines that have been designed and built according to the provisions of this
type-C standard.
vi © ISO 2019 – All rights reserved

DRAFT INTERNATIONAL STANDARD ISO/DIS 4254-18:2019(E)
Agricultural machinery — Safety —
Part 18:
Forage loader wagons and forage transport wagons
1 Scope
This document, intended to be used together with ISO 4254-1, specifies the safety requirements and
their verification for the design and construction of
— trailed loader wagons,
— trailed forage transport wagons,
— silage and forage body intended to be affixed to a carrier vehicle,
— trailers with a load push/push-off device, slats or alternating moving floor
which is intended for the use by only one person (operator). In addition, it specifies the type of
information on safe working practices including residual risks to be provided by the manufacturer.
This document is not applicable to:
— self-propelled loader wagons and self-propelled forage transport wagons,
— trailers with a tipping body, balanced or semi-mounted, used in agriculture.
When requirements of this document are different from those which are stated in ISO 4254-1, the
requirements of this standard take precedence over the requirements of ISO 4254-1 for machines that
have been designed and built according to the requirements of this standard.
This document, taken together with ISO 4254-1, deals with all the significant hazards, hazardous
situations and events relevant to loader wagons and forage transport wagons, when they are used as
intended and under the conditions of misuse that are reasonably foreseeable by the manufacturer (see
Annex A). It is not applicable to hazards by presence of other persons than the operator and hazards
related to noise and moving parts of the power transmission, excluding strength requirements for
guards and barriers.
This document is not applicable to loader wagons and forage transport wagons manufactured before
the date of publication of this document.
2 Normative references
The following referenced documents are indispensable for the application of this European Standard.
For dated references, only the edition cited applies. For undated references, the latest edition of the
referenced document (including any amendments) applies.
ISO 3600, Tractors, machinery for agriculture and forestry, powered lawn and garden equipment —
Operator's manuals — Content and format
ISO 4254-1:2013, Agricultural machinery — Safety — Part 1: General requirements
ISO 12100:2010, Safety of machinery — General principles for design — Risk assessment and risk reduction
ISO 13857:2008, Safety of machinery — Safety distances to prevent hazard zones being reached by upper
and lower limbs
ISO/DIS 4254-18:2019(E)
ISO 11684:1995, Tractors, machinery for agriculture and forestry, powered lawn and garden equipment —
Safety signs and hazard pictorials — General principles
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 4254-1 and ISO 12100 and the
following apply.
3.1
forage loader wagon
machine for automatically load, transport and unload of chopped crops by means of a pick-up device
Note 1 to entry: Unloading is done by power-driven distribution devices which are integrated in the machine
(for example conveyor) and can be done without or with powered distribution devices (for example dosage or
distributor cylinders, cross conveyor belt).
3.1.1
dual-purpose wagon
forage loader wagon which additionally fulfils the characteristics of a forage transport wagon
3.2
forage transport wagon
machine for transport and unloading of chopped crop which is filled from outside the machine
Note 1 to entry: Unloading is done by power-driven distribution devices which are integrated in the machine (for
example conveyor, retractable floor, movable bulkhead) and can be done without or with powered distribution
devices (for example dosage or distributor cylinders, cross conveyor belt).
3.2.1
push-off wagon
forage transport wagon, where the unloading is done by means of power-driven distribution devices
which are integrated in the machine (moving floor with bulkhead)
Note 1 to entry: Unloading can be performed without or with powered distribution devices (for example dosage
or distributor cylinders, cross belt conveyor).
3.3
pick-up
device for gathering a crop from a windrow and conveying the cut crop into the wagon
3.6
articulated drawbar
adjustable device to change the ground clearance at the front of trailed machines
3.7
conveyor
powered device consisting of two or more chains and connected conveyor slats for the purpose of
conveying the shredded crop to the loading platform
3.8
moving floor with bulkhead (push-off device)
hydraulically movable unit for push-off wagons which is horizontally movable from the front end of the
loading space to the rear unloading edge
3.9
dosage / distributer cylinders
powered tools for the purpose of equal distribution of chopped crop
3.10
side door / door / hood
access for operator to the loading space for maintenance and inspection
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ISO/DIS 4254-18:2019(E)
3.11
tailgate
moveable device at the rear of the machine which serves as the rear limit of the load body and which
can be opened to unload the machine
3.12
entry point
precise location at which the conveyor chain engages with the drive sprocket(s)
3.13
nip point
precise location at which the conveyor slats pass by fixed parts of the machine
3.14
reverse operation of the conveyor
temporary movement of the conveyor opposite the direction of the work
3.15
cross-belt conveyer
powered conveying device for unloading of harvested crops perpendicular to the direction of travel of
the machine
3.16
scissors gate body
foldable load body for the purpose of extension of the loading volume
3.17
feeding elements
devices between the pick-up and the loading space that transfer the material from the pick-up to the
bale chamber (for example, stuffer, rotor)
Note 1 to entry: These devices can convey the material towards the centre of the machine (for example, auger).
4 Safety requirements and/or protective/risk reduction measures for all
machines
4.1 General
Machinery shall comply with the safety requirements and/or protective/risk reduction measures of
this clause.
In addition, the machine shall be designed in accordance with the principles of ISO 12100:2010, clause
4, for hazards relevant, but not significant, which are not dealt with by this part of ISO 4254.
The compliance with the safety requirements and / or protective/risk reduction measures shall be
verified in accordance with clause 5.
Unless otherwise specified in this part of ISO 4254, the machine shall comply with the requirements of
ISO 4254-1 and with Tables 1,3, 4 and 6 of ISO 13857:2008.
4.2 Controls
4.2.1 General
The operator shall be unable to reach controls when inside the loading space.
The control(s) shall be located so that it is not possible for the operator to reach unguarded moving
working tools when actuating the control(s). This requirement is deemed to be fulfilled when the
distance between the controls and each unguarded moving working tool during operation is ≥ 850 mm.
ISO/DIS 4254-18:2019(E)
Controls for machines where actuation from the driver's seat is required, shall be designed so that the
operator can reach them for example by means of adjustable position of the controls or possibility of
installation inside the tractor.
These requirements have to be verified by measurement and inspection.
4.2.2 Manual controls
For manual controls the requirements of 4.5 and 6.1 of ISO 4254-1:2013 apply.
In addition,
— unintentional activation of manual controls shall be avoided by design, location or other means;
— the distance between manual controls and hazardous zones of the machine shall exceed 850 mm. If
for the knife sharpening device, the distance of minimum 850 mm cannot be fulfilled, the actuation
of the controls shall be by 2 hands and the controls shall be of hold-to-run type.
4.2.3 Remote controls (with cables or cableless)
Note Proposals expected during next enquiry.
4.3 Stability in parking position
For the stability in parking position, the requirements under 6.2.1 of ISO 4254-1:2013 apply.
Safe means shall be provided to prevent the machine from rolling away when parked.
4.4 Articulated drawbar
Crushing and shearing points in the area of the move parts of the articulated drawbar shall be protected.
Protection can be achieved by:
— safety distances complying with the requirements of ISO 13857:2008, Tables 1, 3, 4 and 6 as
appropriate; or
— in any position of the traversable stroke of the articulated drawbar it has to be met:
— a safety distance of either ≤ 8 mm or ≥ 25 mm between moving and fixed parts;
— an angle α of ≥ 30º or a safety distance of ≥ 25 mm for parts shearing against one another (see
figures 1, 2 and 3).
4 © ISO 2019 – All rights reserved

ISO/DIS 4254-18:2019(E)
Key
1 Ball-type coupling device
2 Drawbar
3 Angle of yaw limiter
4 Hydraulic hose retainer
5 Connection point drawbar – frame (pivot point)
6 Articulated drawbar cylinder
7 Vehicle body
Figure 1 — Articulated drawbar in lowered position
Key
1 Articulated drawbar 4 Vehicle frame
2 Articulated drawbar cylinder 5 Shearing point
3 Connection bolt articulated drawbar – frame 6 Crushing point
(pivot point)
Figure 2 — Cylinder of articulated drawbar in extended position
ISO/DIS 4254-18:2019(E)
Dimensions in Millimetres
Key
1 Articulated drawbar
2 Connection bolt articulated drawbar – frame (pivot point)
3 Vehicle body
Figure 3 — Articulated drawbar – Top view
The articulated drawbar shall be protected against unintentional activation according to 4.11 of
ISO 4254-1:2013 in order to avoid lowering of the vehicle i.e. at maintenance work.
4.5 Pick-up Device
4.5.1 Protection against inadvertent contact with the pick-up device shall be provided by parts of the
machine, guards, barriers or a combination of these. The position of parts which may be adjustable
shall always remain within the limits specified in 4.5.2. The projection on a horizontal plane of these
protective devices shall be continuous.
4.5.2 When the pick-up device is in the working position as defined in the operator's manual, these
barriers shall be positioned as follows:
— the front barrier in a horizontal distance of at least 230 mm in front of the most forward point of the
tine path an in a height h > 500 mm above the ground (see Figure 4a). If the height h is ≤ 500 mm, a
distance of at least 100 mm has to be kept (see Figure 4b). The front barrier is not required if a part
of the machine fulfils this function (i.e. deflector plate, role with reels);
— a minimum of 150 mm of the lateral barrier from the sides of the tine path at a maximum height
above the ground of 500 mm (see Figure 4). The lateral barrier is not required if a part of the machine
fulfils this function (i.e. contact wheel, see Figure 6) or if the tine path is totally covered by a part of
the machine when viewed from the side, as defined and shown in Figure 5.
4.5.3 When the pick-up device is in the working position, side guards, if fitted, shall be located in
accordance with Figure 5.
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ISO/DIS 4254-18:2019(E)
Dimensions in Millimetres
a)
b)
Key
1 Front barrier
2 Lateral barrier
3 Tine path
Figure 4 — Protection of pick-up device by a combination of barriers
ISO/DIS 4254-18:2019(E)
Dimensions in Millimetres
Key
1 Guard or fixed part of the machine
2 Barrier
3 Tine path
NOTE This figure illustrates an example of protective devices complying with 4.5.2.
Figure 5 — Lateral guarding of the pick-up device by a combination of barriers and fixed guards
or parts of the machine
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ISO/DIS 4254-18:2019(E)
a) side view
b) front view
Figure 6 — Lateral guarding of pick-up device by combination of barriers and lateral guide wheels
4.6 Feeding elements and cutting devices
4.6.1 Crushing and shearing points located at a distance of less than 230 mm from the outer limit
of the machine or from the extreme edges of the feeding channel shall be guarded against inadvertent
contact and shall meet the requirements as defined in ISO 13857. In case the elements to convey the
crop laterally are designed as augers, the guard above the auger shall extend forward from the rear of the
auger to at least the longitudinal axis of the auger as shown in Figure 7. Devices other than augers shall
be guarded on top in a comparable manner to meet the requirements as specified in ISO 13857.
4.6.2 A lateral fixed guard partially covering the auger and a distance barrier, in combination with
barriers as defined in 4.5, are deemed to meet the requirements of 4.6 when the dimensions of Figure 7
are respected.
ISO/DIS 4254-18:2019(E)
4.6.3 Principles of safety and ergonomics shall be incorporated to reduce the risk of harm while
changing knives by providing
— the knives can be removed without use of tools, if the operator has to stay underneath the machine
for this purpose. This requirement does not apply for the central locking/unlocking of the knives
from the side of the machine and the use of means for avoiding of cutting hazards when removing
the knife; or
— it is possible to swivel the cutter bar towards the side of the machine.
Specific instructions on the procedures to be followed for the changing as well as sharpening of knives
shall be given in the operator's manual [see 6.1 …)].
Dimensions in Millimetres
Key
1 lateral barrier of conveying and cutting device 5 rear covering above auger
2 front barrier of pick-up 6 feeding auger
3 lateral barrier of pick-up 7 Pick-up
4 lateral fixed separating guard
Figure 7 — Guarding of the feeding elements
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ISO/DIS 4254-18:2019(E)
4.7 Conveyor
4.7.1 Conveyor with slats
4.7.1.1 Guarding
4.7.1.1.1 General
For conveyors with slats, the access to shearing and crushing points shall be prevented by means of
design or fixed guards.
If due to functional reasons, there is still access to shearing and crushing points, the following clauses
shall be fulfilled.
4.7.1.1.2 Moving path of conveyor
The moving path of the conveyor below the load body shall be covered at the front and at the sides over
its entire length, see Figure 8.
Below the load body the distance between the conveyor slats and the fixed parts of the machine located
in the transverse direction to the moving direction of the conveyor (for example frame or slats) except
for guiding elements of the conveyor slats provided that they do not generate shearing or crushing
hazards shall be at least 25 mm, see Figure 9.
This minimum gap of 25 mm shall be maintained after foreseeable slackening of the scraper floor
chains during use. The shape of the lateral guard shall take into account the possible slackening of the
scraper floor chains during use.
Remaining shearing and crushing points between the conveyor and fixed parts of the machine shall be
identified. Such shearing and crushing points shall be identified by safety signs on the machine where
foreseeable access could be gained to these shearing and crushing points. The safety signs and their
position on the machine shall be indicated in the operator's manual (see 6.1 f)).
ISO/DIS 4254-18:2019(E)
Key
1 direction of travel of machine
2 area to be guarded at the front
3 area to be guarded at the sides
4 moving direction of conveyor (upper and lower strand)
Figure 8 — Guarding of moving path of conveyor
Dimensions in mm
a) side view
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ISO/DIS 4254-18:2019(E)
b) perspective view
Key
1 fixed part of the machine – part(s) of the frame
2 fixed part of the machine - chassis
3 lower strand of conveyer
4 moving direction of the conveyor (upper and lower strand)
5 guiding elements for the conveyor
Figure 9 — Guarding of the conveyor below the body
4.7.1.1.3 Front turning points
Shearing and crushing points at a distance of less than 850 mm from the outer contour of the machine,
which are directly accessible from the side of the machine shall be guarded at the front turning points.
If direct access to the front turning points is possible, the horizontal distance between the foremost
point of the front of the moving path of the conveyor and the fixed parts of the machine shall be at least
100 mm, see Figure 10, a).
If access to the front turning points is only possible indirectly (for example by circumventing a guard),
the horizontal distance between the foremost point of the moving path of the conveyor and the fixed
parts of the machine may be minimized to 25 mm. In this case, the lower guard shall extend rearwards
from the fixed parts at least to the vertical plane through the axle of the chain sprocket axle / deflection
rolls. The distance between the moving path of the conveyor and the guard shall be at least 100 mm. The
distance of 100 mm from the outer moving path of the conveyor to the guard shall at least be provided
over a length of 130 mm from the rearward edge of the guard, see Figure 10, b).
When operating in the unloading direction, the areas at the turning points of the conveyor where the
chains run onto a sprocket or deflection roll shall be guarded. The guard shall prevent direct access to
the crushing zones.
As far as a reverse movement of the conveyor is possible, the upper entry point of the conveyor inside
the load body shall be guarded along its width. This does not apply if the machine is equipped with a
hold-to-run control for the reverse operation of the conveyor.
Shearing and crushing hazards which may occur during contact of the conveyor slats with the loading
platform or the guide plates at the turning points and which could not be avoided due to functional
reasons shall be identified by safety signs on the machines where foreseeable access could be gained
ISO/DIS 4254-18:2019(E)
to these shearing and crushing points. The safety signs and their position on the machine shall be
indicated in the operator's manual (see 6.1 e)).
Dimensions in mm
a) Guarding at direct access
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ISO/DIS 4254-18:2019(E)
b) Guarding at indirect access
Key
1 fixed part of the machine (i.e. body or slats)
2 outer moving path of the conveyer
3 direction of travel of the machine
4 moving direction of the conveyor
5 guard
6 rearward edge of the guarding
Figure 10 — Guarding of the conveyor at the front turning points
4.7.1.1.4 Rear turning points
Shearing and crushing points at a distance of less than 850 mm from the outer lateral edge of the
machine which are directly accessible shall be guarded at the rear turning points. This guarding can
be achieved by guide plates that have a clearance between the guide plate and the slats of no more than
8 mm at the area of the turning leave. The maximum clearance of 8 mm shall be maintained by 120° to
the rear of a vertical axis through the centre of the sprocket, see item 1 of key to Figure 11.
When operating in the unloading direction, the areas at the turning points of the conveyor where the
chains run onto a sprocket or deflection roll shall be guarded. The guard shall prevent direct access to
the crushing zones.
As far as a reverse movement of the conveyor is possible, the lower entry point of the conveyor below
the load body shall be guarded along its width. This does not apply if the machine is equipped with a
hold-to-run control for the reverse operation of the conveyor.
Shearing and crushing hazards which may occur during contact of the conveyor slats with the loading
platform or the guide plates at the turning points and which could not be avoided due to functional
reasons shall be identified by safety signs on the machines where foreseeable access could be gained
to these shearing and crushing points. The safety signs and their position on the machine shall be
indicated in the operator's manual (see 6.1 e)).
ISO/DIS 4254-18:2019(E)
Dimensions in mm
Key
1 guide plate
2 direction of travel of the machine
3 moving direction of the conveyor (upper or lower strand)
4 entry point
Figure 11 — Guarding of the conveyor at the rear turning points
4.7.1.2 Adjustment of conveyor
For machines which are not foreseen to be fitted with a pick-up device the tension of the conveyor
chains shall be adjustable without the operator having to get underneath the machine load body (see
6.1., h)).
The requirements given in 4.7.1.1.3 shall be met in all adjustment positions of the front turning point of
the conveyor.
4.7.2 Conveyor belts
Note Proposals for specifications for guarding of conveyor belts are expected during next enquiry.
4.8 Other discharge elements (i.e. push-off wagon)
4.8.1 General
The direct access to crushing and shearing points at push-off devices shall be prevented by design or
fixed guards.
If access to crushing and shearing points is possible due to functional reasons, the following clauses
shall be fulfilled.
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ISO/DIS 4254-18:2019(E)
The control for reverse operation of the push-off device shall be a hold-to-run control.
The safe readjustment and replacement of the sealing and guide slats shall be indicated in the operator's
manual (see 6.1 j)).
4.8.2 Moving path of the push-off device
The moving path of the push-off device shall be covered at the sides and at the front over its entire
length, see Figure 12.
Crushing and shearing points at a distance of less than 850 mm to the outer contour of the machine which
are directly accessible from the side of the machine shall be guarded at the area of the push-off device.
Below the load body the distance between the push-off device and the fixed parts of the machine (i.e.
frame or slats) shall be at least 25 mm, see Figure 13.
Remaining crushing and shearing points between the push-off device and the fixed parts of the
machine shall be identified. These crushing and shearing points shall be identified by safety signs on
the machines where foreseeable access could be gained to these shearing and crushing points. The
safety signs and their position on the machine shall be indicated in the operator's manual (see 6.1 e)).
Figure 12 — Guarding of the moving path of the push-off device
ISO/DIS 4254-18:2019(E)
Dimensions in mm
a) - Side view
b) - Perspective view
Key
1 push-off wall
2 hydraulic cylinder of push-off wall
3 sliding element of front wall
4 guiding elements for the push-off device
5 push floor unit
6 bottom plate
Figure 13 — Guarding of the push-off device below body
4.9 Access to loading space
The operator shall have access to the loading space. If there is a door / hood for this purpose, this
shall preferably be located in the middle of the loading space at the left side (in direction of travel).
Exemptions are possible if the loading space can be accessed without hazard (i.e. front door,
maintenance openings, etc.).
18 © ISO 2019 – All rights reserved

ISO/DIS 4254-18:2019(E)
Opening of the door / hood shall preferably be possible from the ground. If this is not possible boarding
means according to 4.10 shall be provided, and when opening the door / hood a three-point-contact for
the operator shall be possible.
The access opening shall at least have the following dimensions (see Figure 14):
— at a height A of 900 mm to 1200 mm a width B ≥ 600 mm, or
— at a height A from of 1200 mm a width B ≥ 500 mm.
Key
A opening height
B opening width
Figure 14 — Opening for access in kneeling posture
The access to the door / hood shall be guarded.
Access to and the stay in the loading space shall only be possible for maintenance and cleaning and with
the machine switched-off. Appropriate safety signs on the machine shall be provided and warnings
shall be indicated in the operator's manual (see 6.1 d)).
When opened, the door / hood shall be secured against snap shutting.
When closed, the door / hood shall be lockable.
It shall be possible to open automatically locking doors / hoods from inside.
When accessing there shall be no hazards for the operator by crushing and cutting injuries.
4.10 Boarding means
For boarding means the requirements of ISO 4254-1:2013, 4.8 apply.
4.11 Discharging
4.11.1 Dosage cylinders
Note: Specific requirements for the dosage cylinders have to be completed.
ISO/DIS 4254-18:2019(E)
4.11.2 Cross conveyor belt
For prevention of crushing hazards for the fingers the safety distances shall comply with the Tables 1, 3,
4 and 6 of ISO 13857:2008 where applicable.
4.12 Opening and closing of the rear discharge gate
4.12.1 General
The machine shall be designed to avoid:
— impact hazards at the opening of the discharge gate, and
— crushing or shearing hazards at the closing of the discharge gate.
If it is necessary to carry out cleaning and maintenance below the opened discharge gate, the
requirements of ISO 4254-1:2013, 4.11 apply in order to prevent inadvertent lowering. If the device is a
mechanical support, this shall not be detachable.
Endangering of persons staying in the swivelling zone of the discharge gate between gate and platform
of the load body shall be prevented in case of a leakage / hose breakage i.e. by means of a hydraulic lock
valve or hose breakage protection.
Remaining residual risks at opening and closing of the discharge gate shall be identified by safety signs
at the discharge gate and indicated by warnings in the operator's manual.
4.12.2 Opening
To avoid impacts of the rear discharge gate with a bystander, the maximum opening speed of the
discharge gate shall not exceed 1,0 m/s while the vertical distance between the edge of the discharge
gate and the ground is less than 2000 mm (see Annex B).
For machines with discharge gates that only open on a purely vertical plane, this requirement does
not apply.
Verification: The speed tangential to the trajecto
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