SIST EN 17088:2021

SLOVENSKI STANDARD
01-september-2021
Sistemi prezračevanja stranskih zaves - Varnost
Side curtains ventilation systems - Safety
Lüftungssysteme mit Seitenvorhang - Sicherheit
Systèmes de ventilation à rideau latéral - Sécurité
Ta slovenski standard je istoveten z: EN 17088:2021
ICS:
65.040.10 Poslopja, naprave in oprema Livestock buildings,
za živino installations and equipment
91.140.30 Prezračevalni in klimatski Ventilation and air-
sistemi conditioning systems
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 17088
EUROPEAN STANDARD
NORME EUROPÉENNE
July 2021
EUROPÄISCHE NORM
ICS 65.040.10; 91.140.30; C
English Version
Side curtain ventilation systems - Safety
Systèmes de ventilation à rideau latéral - Sécurité Lüftungssysteme mit Seitenvorhang - Sicherheit
This European Standard was approved by CEN on 30 May 2021.

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-CENELEC 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-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, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 17088:2021 E
worldwide for CEN national Members.

Contents Page
European foreword . 4
Introduction . 5
1 Scope . 6
1.1 General . 6
1.2 Exclusions . 6
2 Normative references . 6
3 Terms and definitions . 7
4 List of hazards . 9
5 Requirements . 10
5.1 General . 10
5.2 Mechanical requirements . 10
5.2.1 General . 10
5.2.2 Mechanical strength . 10
5.2.3 Resistance to wind load . 10
5.2.4 Steel wire ropes, synthetic ropes, and straps . 11
5.2.5 Mechanical durability . 12
5.2.6 Protection against cutting and abrasion. 12
5.2.7 Mechanical maintenance . 12
5.3 Requirements for moving parts (excluding drawing-in points) . 13
5.4 Requirements for drawing-in points . 13
5.4.1 General . 13
5.4.2 Type of material creating drawing-in point . 14
5.4.3 Type of person(s) in contact with the system . 15
5.4.4 Drawing-in protection measures . 16
5.4.5 Scenarios with indirect exposed requirements and different persons . 17
5.4.6 Selection of Protection Methods for a Drawing-In Point . 22
5.5 Electrical requirements . 23
5.5.1 General . 23
5.5.2 Main switch. 23
5.5.3 Re-establishing power to the system . 23
5.5.4 Protection of cables to livestock . 23
5.6 Emergency stop . 23
5.6.1 Architecture . 23
5.6.2 Where to locate the emergency stop(s) . 24
5.7 Electromagnetic compatibility (EMC) . 24
5.8 Noise . 24
5.9 Documentation . 25
5.9.1 General . 25
5.9.2 Installation . 25
5.9.3 Labelling . 25
5.9.4 Handover . 26
5.9.5 Operation and use . 26
5.9.6 Maintenance and repairs. 27
5.9.7 Dismantling . 27
6 Evaluation of Conformity . 27
6.1 General . 27
6.2 Statement of applicable hazards . 28
6.3 Curtain testing . 28
6.3.1 Initial type test . 28
6.3.2 Test on site . 28
6.4 Verification of requirements . 28
6.4.1 General . 28
6.4.2 Mechanical Requirements ( 5.2) . 30
6.4.3 Mechanical maintenance (5.2.7) . 30
6.4.4 Moving parts, excluding drawing-in points (5.3) . 30
6.4.5 Drawing-in points (5.4) . 30
6.4.6 Electrical (5.5) . 30
6.4.7 Noise (5.8) . 30
6.4.8 Production control . 30
Annex A (informative) Some example forms of side curtains . 32
Annex B (informative) Roles and responsibilities in the supply chain . 37
Annex C (informative) List of significant hazards . 39
Annex D (normative) Clarification of the requirements for pull out load . 42
Annex E (informative) Form risk analysis, assessment and reduction . 46
Annex F (normative) Resistance to wind . 48
Annex G (informative) Clarification of the requirements for safety barrier to provide 'In-
directly Exposed' criteria for drawing-in hazards . 52
Annex H (informative) Environmental aspects for Side Curtain Ventilation Systems . 54
Annex ZA (informative) Relationship between this European Standard and the
requirements of Directive 2006/42/EC aimed to be covered . 61
Bibliography . 63

European foreword
This document (EN 17088:2021) has been prepared by Technical Committee CEN/TC 422 “Side curtains
ventilation systems - safety”, the secretariat of which is held by NEN.
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 January 2022, and conflicting national standards shall
be withdrawn at the latest by January 2022.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document has been prepared under a standardization request given to CEN by the European
Commission and the European Free Trade Association, and supports essential requirements of
EU Directive 2006/42/EC.
For relationship with EU Directive, see informative Annex ZA, which is an integral part of this document.
Any feedback and questions on this document should be directed to the users’ national standards body.
A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organisations of the
following countries are bound to implement this European Standard: 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, Turkey and the United
Kingdom.
Introduction
In 2010, there was a fatal accident when a child of a farmer was trapped by an automatic stable display.
This accident happened both in the Netherlands and Belgium.
This accident triggered some Dutch experts to use the existing Dutch Technical Agreement NTA 8344:
2012 “Side curtains – Safety” for the development of the first European Standard “Side systems curtains
ventilation systems – Safety”.
This standard is a type-C standard as specified in EN ISO 12100:2010.
The machinery concerned and the extent to which hazards are covered are indicated in the scope of this
standard. These hazards are specified to the Side curtains ventilation systems.
Where provisions of this type C are different from those which are stated by type A or B standards, the
provisions of this type C standard take precedence over the provisions of the other standards, for
machines that have been designed and built according to the provisions of this type C standard.
In order to make the objective of this concept clear and eliminate uncertainties when reading it, the
following assumptions are made:
a) components without specific requirements are components
1) designed according to the common design and calculation methods, including all failure
mechanisms;
2) of a solid mechanical and electrical construction;
3) manufactured from sufficiently strong material with a suitable quality;
4) of which general electrical hazards are dealt with by application of the standards for electrical
installations, such as EN 60204-1:2018;
b) with the exception of the following provisions, is a mechanical supply built according to the
requirements of good craftsmanship and the requirements in this standard concept:
1) agreements between the manufacturer and the buyer about the special conditions of use, and
place where the screen is used in connection with health and safety;
2) the location of the installation will be suitable for this;
3) the place of installation will allow a safe use of the screen.
These assumptions do not limit the need for sufficient information in this concept standard before use.
1 Scope
1.1 General
This document specifies the standardization of side curtain ventilation systems as defined in 3.1. This
document specifies the safety aspects and performance. Included are machines that operate using the
potential energy stored by the earlier application of human or animal force, such as stretched springs.
This document addresses the following significant hazards associated with side curtain systems:
— crushing;
— cutting or severing;
— drawing-in or trapping;
— entanglement;
— shearing;
— suffocation;
— electrocution and shock;
— incorrect design, location or identification of control devices.
1.2 Exclusions
This document does not apply to the following, which are intended for a different use:
— doors and side curtains when used as doors which are specified in EN 13241:2003+A2:2016;
— systems inflated by air;
— screens supplied for the control of fire or smoke;
— screens that move instantaneously upon the application of human force;
— side curtains when used to control ventilation conditions in a toxic or explosive environment.
This document is not applicable to side curtain ventilation systems manufactured before the date of its
publication.
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.
1)
EN 1991-1-4:2005 , Eurocode 1: Actions on structures - Part 1-4: General actions - Wind actions
EN 14717:2005, Welding and allied processes - Environmental check list

1) As impacted by EN 1991-1-4:2005/A1:2010.
EN 60204-1:2018, Safety of machinery - Electrical equipment of machines - Part 1: General requirements
(IEC 60204-1:2016)
EN IEC 61000-6-2:2019, Electromagnetic compatibility (EMC) - Part 6-2: Generic standards - Immunity
standard for industrial environments (IEC 61000-6-2:2016)
2)
EN 61000-6-3:2007 , Electromagnetic compatibility (EMC) - Part 6-3: Generic standards - Emission
standard for residential, commercial and light-industrial environments (IEC 61000-6-3:2006)
3)
EN 62061:2005 , Safety of machinery - Functional safety of safety-related electrical, electronic and
programmable electronic control systems (IEC 62061:2005)
EN ISO 12100:2010, Safety of machinery - General principles for design - Risk assessment and risk reduction
(ISO 12100:2010)
EN ISO 13849-1:2015, Safety of machinery - Safety-related parts of control systems - Part 1: General
principles for design (ISO 13849-1:2015)
EN ISO 13849-2:2012, Safety of machinery - Safety-related parts of control systems - Part 2: Validation (ISO
13849-2:2012)
EN ISO 13850:2015, Safety of machinery - Emergency stop function - Principles for design (ISO 13850:2015)
EN ISO 13857:2019, Safety of machinery - Safety distances to prevent hazard zones being reached by upper
and lower limbs (ISO 13857:2019)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN ISO 12100:2010 and the
following apply.
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 https://www.electropedia.org/
3.1
side curtain ventilation systems
systems supplied for environmental control, installed on farm buildings, that use a barrier made from a
flexible foil or fabric which moves via a rolling or folding action, or rigid panels that slide
3.2
automatic control
action where the screen is operated without human intervention

2) As impacted by EN 61000-6-3:2007/A1:2011.
3) As impacted by EN 62061:2005/A1:2013 and EN 62061:2005/A2:2015.
3.3
environmental aspect
element of an organization's activities or products or services that can interact with the environment
Note 1 to entry: A significant environmental aspect has or can have a significant environmental impact.
[SOURCE: EN ISO 14001:2015, 3.2.2 – modified, Note 1 to entry has been modified and Note 2 to entry
has been deleted.]
3.4
environmental impact
change to the environment, whether adverse or beneficial, wholly or partially resulting from an
organization's environmental aspects
[SOURCE: EN ISO 14001:2015, 3.2.4]
3.5
folded screen
curtain which is mounted in such a way when opened it is folded
Note 1 to entry: In Annex A, some versions of side curtain ventilation systems with their operating principles are
mentioned.
3.6
life cycle assessment
LCA
compilation and evaluation of the inputs, outputs and the potential environmental impacts of a product
system throughout its life cycle
[SOURCE: CEN/TR 13910:2010, 3.1]
3.7
moveable curtain
automatically- or manually-operated, mechanical- or electric-powered protection against, among other
things, weather influences, capable of moving
Note 1 to entry: The curtain has a power drive: this can be mechanical, electrical, pneumatic or hydraulic.
3.8
packaging
all items made of any material of any nature to be used for the containment, protection, handling, delivery
and presentation of goods, from raw materials to processed goods, from the producer to the user or the
consumer
Note 1 to entry: In this report, the goods are referred to as “packaged product” or “product”, in order to
distinguish it from the packaging.
[SOURCE: CEN/TR 13910:2010, 3.5]
3.9
prevention of pollution
use of processes, practices, techniques, materials, products, services or energy to avoid, reduce or control
(separately or in combination) the creation, emission or discharge of any type of pollutant or waste, in
order to reduce adverse environmental impacts
Note 1 to entry: Prevention of pollution can include source reduction or elimination, process, product or service
changes, efficient use of resources, material and energy substitution, reuse, recovery, recycling, reclamation and
treatment.
[SOURCE: EN ISO 14001:2015, 3.2.7]
3.10
rigid panel
vertical lifting panel for ventilation purposes manually and/or power operated and interlinked by a
flexible device (e.g. cable, chain, rope…)
Note 1 to entry: The rigid panel is installed on the wall of a building.
3.11
roller blind
rollable curtain where the screen rolls on a tube during opening and closing
3.12
integrated safety component
component which fulfils a safety function within the completed machine and cannot be separated from
machinery without modification in the design, therefore cannot be independently placed on the market
3.13
single rolling curtain
rolling element of the curtain, usually at the lower extremity of the curtain, takes in a single foil as it
rotates, as shown in Annex A Type D, Type F and Type H
3.14
double rolling curtain
rolling element of the curtain, usually situated in the centre of the curtain, takes in two foils as it rotates,
as shown in Annex A Type E, Type G and Type I
3.15
pulse action
amount an automated side curtain will be driven in a continuous movement before stopping
3.16
pause interval
period of time an automated side curtain will remain stationary between two pulse actions
4 List of hazards
This clause contains all the significant hazards, risk areas and hazardous situations and events as far as
they are dealt with in this document, identified by risk assessment performed according to
EN ISO 12100:2010 as significant for this type of machinery and which require action to eliminate or
reduce the risk. See Annex C, Table C.1.
5 Requirements
5.1 General
Machinery shall comply with the safety requirements and/or protective/risk reduction measures of this
clause. In addition, the machine shall be designed according to the principles in EN ISO 12100:2010 for
relevant but not significant hazards which are not dealt with by this document.
The manufacturer shall perform a risk analyses, assessment and reduction process. For an example how
to perform such a process, see Annex E.
5.2 Mechanical requirements
5.2.1 General
Side curtain systems shall be designed and constructed so that they are capable of being installed,
maintained, repaired, used and dismantled in a safe manner.
5.2.2 Mechanical strength
The side curtain and its components, including its fixings for attachment to the building, shall be designed
so that, during normal operation, no part of the system, including the fixings, shall be permanently
deformed.
The side curtain shall be designed so that elastic deformations under operational forces or torques which
occur during normal use do not affect the function of the system.
The design shall be in accordance with recognized engineering stress/yield calculations or test methods
using adequate safety factors, see Table 1, taking into account the most unfavourable static and dynamic
forces occurring during the operating cycle or the use of the safety equipment within the side curtain.
Table 1 —Safety factors
Loading conditions Safety factors for calculation Safety factor for testing
purposes purposes
Stress due to differential 1,5 min breaking stress 1,0
pressure
Stress due to other loads 1,5 min breaking stress 1,0
(e.g. dead weight)
5.2.3 Resistance to wind load
The resistance to wind load of a side curtain is its capacity to withstand a specified differential wind
pressure.
NOTE The construction of the side curtain system depends on the pressure of a number of factors including,
e.g. the maximum wind speed anticipated in the area, the location, height, size and shape of the building, and the
position of the side curtain on the building.
When definite wind load classes or pressures are not stated by the specifier, side curtains shall be
designed in order to resist specified differential wind pressure, and shall be classified with the wind load
classes as specified in Annex F. See Figure F.1 for a typical wind map of Europe.
The requirements of this clause apply to the ability of the closed side curtain and not to their ability to be
opened or closed under wind load.
For correct operation of side curtains, the manufacturer shall state the maximum wind speed (within the
operating instructions, 5.9.4) where the system can be operated without risk of failure of the system.
The deflection of the curtain or other elements resulting from the differential pressure specified shall not
cause permanent deformations which will affect the functioning of the system or create any risk of
jamming.
5.2.4 Steel wire ropes, synthetic ropes, and straps
5.2.4.1 General
Steel wire ropes, synthetic ropes, and straps, etc. shall be suitable for the intended application with
regards to strength, durability and corrosion resistance.
For suspension elements, a single wire rope, synthetic rope, or strap, etc. can only be used if a failure of
the element will result in the curtain falling under gravity in a safe manner, i.e. the falling curtain will be
restrained in a controlled manner that would not expose people near to it to increased risk of crushing,
shearing, entanglement, drawing-in or trapping.
Where two or more suspension elements are used, it shall be ensured that the dead loads are shared in a
pre-determined way.
The guaranteed minimum breaking strength of such a suspension element determined by calculations of
the maximum load it has to support, multiplied by the safety factor (Table 1).
All such suspension elements shall have terminations and/or joints with a breaking load of no less than
90 % of that of the element, or a suspension element safety factor design working load. Terminations on
a drum shall always have a minimum of two full turns left on a drum in the terminal position. Measures
shall be taken to ensure that terminations cannot be accidentally detached.
Where such suspension elements enter grooves on drums or pulleys, the design shall ensure that the
elements are aligned correctly to allow entry of the suspension elements.
Suspension element drums mounted up to a height of 2,7 m above floor level or another permanent level
shall be fitted with a guard.
5.2.4.2 Steel wire ropes
For steel wire ropes, where failure of the rope would result in increased levels of risk to crushing,
shearing, entanglement, drawing-in or trapping:
— each steel wire rope shall have a safety factor of no less than 6 (minimum breaking strength/static
load);
— rope pulleys and rope drums shall have a pitch circle diameter (P.C.D.) at least equal to 20 times the
rope diameter;
— rope drums shall be grooved, and the ropes coiled in only one layer;
— rope pulleys shall be designed so that the steel wire rope cannot jump out of the pulley.
Steel wire ropes used commonly in systems typically will not result in increased levels of risk, i.e. if the
curtain falls down in safe manner (e.g. within the wind bracing). For steel wire ropes where failure of the
rope would not result in increased levels of risk:
— each steel wire rope shall have a safety factor of no less than 3 (minimum breaking strength/static
load);
— rope pulleys and rope drums which have a pitch circle diameter (P.C.D.) less than 20 times the rope
diameter shall be tested so as to ascertain the number of cycles until failure of the cable when
supporting the design load. This number of cycles shall then be used in calculating the service life of
the rope, and this then stated in the operating instructions, 5.9.4, to the end user.
5.2.4.3 Synthetic ropes and straps
For a synthetic rope or strap where failure of the rope would result in increased levels of risk to crushing,
shearing, entanglement, drawing-in and trapping, the rope or strap shall have a safety factor not smaller
than 6 (minimum breaking strength/static load).
For a synthetic rope or strap where failure of the rope would not result in increased levels of risk, the
rope or strap shall have a safety factor not smaller than 3 (minimum breaking strength/static load).
5.2.5 Mechanical durability
A side curtain is subject to dynamic forces both from weather and from the curtain itself moving. The
manufacturer of the system shall consider the presence of these dynamic forces when specifying
components and fixings within the product.
The mechanical performance of the side curtain shall be ensured, subject to prescribed maintenance, for
a number of operational cycles or a minimum time period when operated automatically, to be declared
by the manufacturer.
5.2.6 Protection against cutting and abrasion
There has to be protection against cutting and shearing, either with guarding the dangerous zones or
using combinations of risk reducing methods. A speed of v < 33 mm/s is seen as safe against cutting and
shearing with adult persons. With children, the combination of a speed of v < 33 mm/s and pulse-pause
(5.4.4.2) in automatic mode, the risk is effectively minimized.
As far as their purpose allows, accessible parts of the machinery shall have no sharp edges, no sharp
angles and no rough surfaces which are likely to cause injury.
5.2.7 Mechanical maintenance
5.2.7.1 General
The following requirements for through life maintenance of the side curtain shall be adhered to in the
design of the system. Subclause 5.9 details the documentation required to advise the end user of when
and how the system will need to be maintained to ensure through life safe operation.
5.2.7.2 Machinery maintenance
Adjustment and maintenance points shall be located outside of danger zones. It shall be possible to carry
out adjustment, maintenance, repair, cleaning and servicing operations while the system is at a standstill.
The machine has to be cut off from the energy supply and any remaining or stored energy discharged.
Components that may have to be changed routinely throughout the operating life of the system (stated
in the maintenance instructions, 5.9.6) shall be capable of being removed and replaced easily and safely.
Access to the components shall enable these tasks to be carried out with the necessary technical means
in accordance with a specified operating method.
5.2.7.3 Access to workplaces and servicing areas
The side curtain shall be designed and constructed in such a way as to allow safe access to all areas where
intervention is necessary during operation, adjustment and maintenance.
Fixed guards shall be used to protect people from hazards when in general operation which are then
required to be removed for maintenance purposes. Such guards will conform to the requirements
referred to in 5.4.4.3.
5.2.7.4 Disconnecting power sources
The machine shall be fitted with mechanisms with which it can be disconnected from each of its power
sources. These mechanisms shall be clearly identified. It shall be possible to lock them if the reconnection
could endanger people exposed to this risk. It shall also be possible to lock the mechanism if an operator
is unable to check that the power is still cut off from any of the locations where he should be.
5.2.7.5 Energy supply other than electricity
When a machine comprises, drives or stores energies other than electricity, this shall be designed,
constructed and defined in such a way that all potential risks involved are excluded.
Forms of energy other than electricity can be:
— potential energy from static forces;
— linetic energy from dynamic forces;
— energy stored in springs; or
— kinetic or potential energy from wind, snow or ice load present at the time.
It shall be possible to discharge the remaining or stored energy that may be present after disconnecting
the machine, without endangering the persons exposed to this risk.
Notwithstanding the requirement given in 5.2.7.4, certain circuits may remain connected to their energy
sources in order, for example, to hold parts in place, to protect information, light interiors and so on. In
this case, special precautions shall be taken to ensure the safety of the operators.
5.3 Requirements for moving parts (excluding drawing-in points)
The mechanical features of a side curtain shall be designed so that the risk to the operator and adjacent
persons of crushing, shearing, entanglement, and trapping is eliminated as far as possible.
Closing gaps which are accessible during the curtain movement shall be eliminated or guarded up to a
height of 2,7 m above floor level or other permanent access level.
The movement of the side curtain towards its end positions, and potential hazardous overrunning of the
end positions needs to be considered.
5.4 Requirements for drawing-in points
5.4.1 General
To determine the necessary protective measures required for an identified drawing-in point, a number
of factors have to be considered. These factors and conditions (referred to in Annex C, C.2.2 degree of
automation) each influence the associated level of risk involved with the drawing-in point.
The following 5-stage process shall be used to evaluate the technical conditions for the drawing-in point
which can then be combined to detail the minimum protective measures that shall be applied.
Stage 1: Define the degree of automation of the side curtain, subclause C.2.2
Stage 2: Define the type of material creating the drawing-in point, subclause 5.4.2
Stage 3: Define the type of person in contact with the drawing-in point, subclause 5.4.3
Stage 4: Consider which of the protection methods available are applicable for the drawing-in point,
subclauses 5.4.4 and 5.4.5
Stage 5: Selection of the minimum level of protection methods that shall be used dependent on conditions
defined in stages 1, 2 and 3, 5.4.5
NOTE Drawing-in points more than 2,7 m above the floor level or other permanent access level do not need to
be protected.
5.4.2 Type of material creating drawing-in point
5.4.2.1 General
The material creating the drawing-in point can be flexible or non-flexible. The risks associated with a
drawing-in point caused by a non-flexible material are much higher due to them causing immediate harm
to body parts and a stronger trapping force reducing the likelihood of avoidance or escape. The risks
associated with a drawing-in point caused by a flexible material are less than a non-flexible fabric as they
may not cause immediate harm to body parts and have a reduced trapping force that may be allow for
avoidance or escape from the hazard. However, the risks of a drawing-in point can still be severe and
shall be addressed appropriately.
The requirements to define a non-flexible and flexible material are detailed in 5.4.2.2 and 5.4.2.3
respectively.
5.4.2.2 Drawing-in points of non-flexible material

Figure 1 — Definition test of a non-flexible material
A material is to be considered non-flexible if it can support (not fold or collapse) a 1N load that is applied
at 50 mm offset when a maximum 10 mm wide sample material is cantilevered horizontally from a
clamped point, Figure 1. This may include a wire rope being wrapped around a drum or an exposed
rotating gear.
5.4.2.3 Drawing-in points of flexible materials

Figure 2 — Definition test of a flexible material
A material is to be considered flexible if it cannot support a 1N load (folds/collapses/creases) that is
applied at 50 mm offset when a maximum 10 mm wide sample of the material is cantilevered horizontally
from a clamped point, Figure 2. This may include a fabric cloth being wrapped around a rigid member.
5.4.3 Type of person(s) in contact with the system
Consideration of both the type of person using the side curtain and the people exposed to the drawing-in
point need to be evaluated in respect to their level of training and/or knowledge of the system. If people
are untrained and/or do not have a knowledge of the system, the risks associated with the drawing-in
point can be higher and therefore require additional protection methods.
The following category levels which are based on three different types of use are specified as follows:
— Type 1A: A limited group of persons are trained to operate the side curtain and the identified hazards
are out of a public area and only accessed by restrained animals;
— Type 1B: A limited group of persons are trained to operate the side curtain and the identified hazards
are out of a public area and accessed by limited people;
— Type 2: A limited group of persons are trained to operate the side curtain and the identified hazards
of side curtain are located within a public area and so are potentially in contact with the general
public;
— Type 3: Any person is free to operate the side curtain and the identified hazards of the side curtain
are in contact with the general public.
NOTE 1 Persons can be considered as “trained” if the employer, the premises supervisor or the premises owner
has allowed them to use the side curtain and has advised them how to use the side curtain.
NOTE 2 A group of persons can be considered to be “limited” if the group consists of identified employees of the
company or identified members of a family 14 years and above.
NOTE 3 An area can be considered “public” if it can be accessed by persons that are not considered “limited”. A
public area will consider persons of all ages.
NOTE 4   Any person under the age of 14 years will be considered public due to their awareness of danger (even if
they are a member of a limited group).
For systems that have been specified to operate under “non-public” conditions, in the situation of an event
making the farm accessible to the “public”, the operating Instructions should state that the user is to
disable to the machine during these periods
A farm yard in its normal rural environment cannot be assessed as being public and so is not accessible
to the general public.
5.4.4 Drawing-in protection measures
5.4.4.1 General
One or a combination of the following protection methods are available for identified hazards of side
curtain ventilation systems. Which protection methods to use are dependent on the degree of automation
system and the environment in which it is located, refer to Table 5 'Requirements for drawing in points
of non-flexible material' and Table 6 'Requirements for drawing in points of flexible material'of 5.4.6.
A Hold-to-run controls mounted in line of sight of system
B Hold-to-run control with key switch or similar
C Low Frequency of Exposure, Limitation of pull out load, Indirectly Exposed Hazard ( refer to
requirements in 5.4.4.2)
D Guarding to EN ISO 13857:2019 (refer to requirements in 5.4.4.3)
5.4.4.2 Frequency of operation, limitation of pull-out load, indirectly exposed hazard (C)
For automatically controlled systems, the manufacture shall determine the frequency of operation
(sensitivity) of the drive that causes the drawing- in hazard.
The frequency of operation (in the drawing-in direction) shall be less than 3 % (determined by 15 min
cumulated exposure per 8 h, see also ISO/TR 14121-2:2012).
NOTE In that case, it can be assumed that the frequency of exposure to the drawing-in hazard is low.
If a person becomes trapped in a drawing-in point, but the pull out load to extract the person or object is
limited to a specific level, then it may be considered possible to avoid or reduce the harm caused. The
limitation of the pull out load depends on several aspects:
— For persons of 14 years and above who have access to the system, a maximum speed of movement
of 33 mm/s combined with a Pulse-Pause method (limited movement). After a singular Pulse-action a
maximum pull out load of 150 N is required. See Annex D for test methods and further explanation,
including Figures D.1 to D.6.
— After a Pulse-action there has to be a pause of at least 10 s.
The speed and the Pulse-Pause manner is a part of the safety function of the controller. The safety
function of the controller therefor
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