ISO 12648:2003

INTERNATIONAL ISO
STANDARD 12648
First edition
2003-04-01
Graphic technology — Safety
requirements for printing press systems
Technologie graphique — Exigences de sécurité pour systèmes de
presses d'impression
Reference number
©
ISO 2003
PDF disclaimer
This PDF file may contain embedded typefaces. In accordance with Adobe's licensing policy, this file may be printed or viewed but
shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In
downloading this file, parties accept therein the responsibility of not infringing Adobe's licensing policy. The ISO Central Secretariat
accepts no liability in this area.
Adobe is a trademark of Adobe Systems Incorporated.
Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation
parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In
the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below.

©  ISO 2003
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or
ISO's member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland
ii © ISO 2003 — All rights reserved

Contents Page
Foreword. v
Introduction . vi
1 Scope. 1
2 Classifications. 1
2.1 Machines for producing printing by various processes. 1
2.2 Auxiliary equipment. 2
3 Normative references . 2
4 Terms and definitions. 4
5 Guarding of significant hazards . 13
5.1 Guards. 13
5.2 In-running (in-going) nips . 15
5.3 Guarding in-running nips. 16
5.4 Interlocks . 19
5.5 Hold-to-run controls . 21
5.6 Automatic format setting operations . 23
5.7 Other safeguarding measures . 23
5.8 Guarding of machine devices and components. 24
6 Requirements for protection against other hazards . 35
6.1 Fire and explosion . 35
6.2 Spillage from washing devices. 39
6.3 Electrical equipment . 40
6.4 Working platforms, access stairs, passageways and raised workplaces . 40
6.5 Stability . 43
6.6 High contact temperatures. 44
6.7 Noise. 44
6.8 Electrostatic toner dust. 45
6.9 Radiation hazards . 45
6.10 Stationary knives . 46
6.11 Rotary tools . 46
6.12 Hazardous tools . 46
6.13 Protruding machine parts . 47
6.14 Handwheels and cranks . 47
6.15 Washing equipment . 47
6.16 Alcohol dosing devices. 47
6.17 Refrigerating devices in ink and dampening units. 48
6.18 Powder spraying devices. 48
6.19 Routine handling of heavy machine parts. 48
6.20 Oxidizers, incinerators or thermal cleaning plants . 48
7 Release from hazardous situation . 49
8 Control zones . 49
9 Controls. 50
9.1 Manual control devices . 50
9.2 Initiating machine motion. 58
9.3 Hold-to-run controls . 59
9.4 Two-hand controls . 59
9.5 Electro-sensitive protective devices. 60
9.6 Pressure-sensitive mats, pressure-sensitive bumpers, trip devices . 60
9.7 Braking devices, clutches .61
10 Control stations.61
10.1 Location of operator control stations .62
10.2 Operator control station orientation.62
10.3 Typical operator control stations .62
10.4 Motion control stations.62
11 Control systems .66
11.1 General requirements .66
11.2 Additional requirements for hand-fed machines where the operator's hands enter the
point of operation.67
11.3 Control systems for screen printing presses.68
12 Ergonomics and labelling of indicators and actuators .68
13 Signals and warning devices .68
13.1 Audible warning system .69
13.2 Area light warning system.72
14 Warning signs and labels .72
15 Information for use.73
15.1 Minimum requirements for machine markings .73
15.2 Contents of instruction handbook.74
Annex A (informative) Hazards on printing press systems.78
Annex B (normative) Explosion protection zones .81
Annex C (informative) Risk analysis relating to the pitch angle of access stairs.84
Annex D (informative) Example of layout of instruction handbooks .86
Annex E (normative) Area warning light system.88
Bibliography.90

iv © ISO 2003 — All rights reserved

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 12648 was prepared by Technical Committee ISO/TC 130, Graphic technology.
Introduction
During the development of this International Standard, existing relevant standards of other countries were
taken into consideration. An effort has been made to harmonize the requirements of all countries, recognizing
that national standards or laws may dictate national requirements. In cases where it was known that there is a
national requirement that differs from this International Standard, that has been noted.
This International Standard has taken into consideration material contained in ANSI B65.1-1995 Safety
standard — Printing press systems, prEN 1010-1, Technical safety requirements for the design and
construction of printing and paper converting machines — Part 1: Common requirements, and prEN 1010-2,
Technical safety requirements for the design and construction of printing and paper converting machines —
Part 2: Printing and varnishing machines including pre-press machinery.

vi © ISO 2003 — All rights reserved

INTERNATIONAL STANDARD ISO 12648:2003(E)

Graphic technology — Safety requirements for printing press
systems
1 Scope
This International Standard applies to printing press systems, including auxiliary equipment and finishing
machines, in which all the machine actuators (e.g. drives) of the equipment in the system are controlled by the
same control system.
It is applicable only to systems in which a printing press is part of the system. In cases where a
binding/finishing system is not integrated with a printing press, ISO 12649 will apply.
This International Standard provides safety requirements for the design and construction of the classes of
machines listed in Clause 2. It addresses recognized hazards specific to printing press systems in the
following areas:
 mechanical;
 electrical;
 slipping, tripping, falling;
 ergonomics;
 noise;
 radiation;
 fire and explosion;
 thermal;
 emissions.
This International Standard applies to new machines (see Clause 2) manufactured after December 31 of the
year following the year of publication of this International Standard.
2 Classifications
2.1 Machines for producing printing by various processes
 relief (letterpress, flexographic);
 offset (lithographic);
 gravure (rotogravure, intaglio);
 screen printing;
 digital presses (electrostatic, ink jet, thermal, airbrush, etc.).
2.2 Auxiliary equipment
 washing equipment for cylinders and rollers;
 powder spraying devices;
 alcohol dosing devices;
 imprinting/addressing/numbering equipment;
 automatic plate clamping devices, automatic pile handling equipment;
 washing equipment;
 inserting machines;
 pile turners, reel turners, elevators;
 dryers/pollution control;
 radiation equipment;
 in-line processing and finishing equipment;
 stackers;
 palletizers;
 bundlers;
 coaters;
 chilling systems;
 electrostatic equipment;
 humidifiers;
 accumulating or piling-off devices;
 conveyors;
 unwinding, rewinding, reel transport devices.
3 Normative references
The following referenced documents are indispensable for the application 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 8031, Rubber and plastics hoses and hose assemblies — Determination of electrical resistance
ISO 11553, Safety of machinery — Laser processing machines — Safety requirements
ISO/TR 11688-1, Acoustics — Recommended practice for the design of low-noise machinery and
equipment — Part 1: Planning
ISO 12100-1, Safety of machinery — Basic concepts, general principles for design — Part 1: Basic
terminology, methodology
2 © ISO 2003 — All rights reserved

ISO 12100-2, Safety of machinery — Basic concepts, general principles for design — Part 2: Technical
principles
ISO 13849-1:1999, Safety of machinery — Safety-related parts of control systems — Part 1: General
principles for design
ISO 13850:1996, Safety of machinery — Emergency stop — Principles for design
ISO 13851, Safety of machinery — Two-hand control devices — Functional aspects and design principles
ISO 13852:1996, Safety of machinery — Safety distances to prevent danger zones being reached by the
upper limbs
ISO 13854, Safety of machinery — Minimum gaps to avoid crushing of parts of the human body
ISO 13855, Safety of machinery — Positioning of protective equipment with respect to the approach speeds of
parts of the human body
ISO 13856-1, Safety of machinery — Pressure-sensitive protective devices — Part 1: General principles for
design and testing of pressure-sensitive mats and pressure-sensitive floors
ISO 14119:1998, Safety of machinery — Interlocking devices associated with guards — Principles for design
and selection
ISO 14120, Safety of machinery — Guards — General requirements for the design and construction of fixed
and movable guards
ISO 14122-1, Safety of machinery — Permanent means of access to machinery — Part 1: Choice of fixed
means of access between two levels
ISO 14122-2, Safety of machinery — Permanent means of access to machinery — Part 2: Working platforms
and walkways
ISO 14122-3, Safety of machinery — Permanent means of access to machinery — Part 3: Stairs, stepladders
and guard-rails
ISO 14122-4, Safety of machinery — Permanent means of access to machinery — Part 4: Fixed ladders
IEC 60079-1, Electrical apparatus for explosive gas atmospheres — Part 1: Flameproof enclosures “d”
IEC 60079-2, Electrical apparatus for explosive gas atmospheres — Part 2: Pressurized enclosures “p”
IEC 60079-5, Electrical apparatus for explosive gas atmospheres — Part 5: Powder filling “q”
IEC 60079-6, Electrical apparatus for explosive gas atmospheres — Part 6: Oil-immersion “o”
IEC 60079-7, Electrical apparatus for explosive gas atmospheres — Part 7: Increased safety “e”
IEC 60079-11, Electrical apparatus for explosive gas atmospheres — Part 11: Intrinsic safety “i”
IEC 60079-14, Electrical apparatus for explosive gas atmospheres — Part 14: Electrical installations in
hazardous areas (other than mines)
IEC 60079-18, Electrical apparatus for explosive gas atmospheres — Part 18: Encapsulation “m”
IEC 60204-1:2000, Safety of machinery — Electrical equipment of machines — Part 1: General requirements
IEC 60825-1, Safety of laser products — Part 1: Equipment classification, requirements and user’s guide
IEC 60947-5-1, Low-voltage switchgear and controlgear — Part 5-1: Control circuit devices and switching
elements — Electromechanical control circuit devices
IEC 61010-1, Safety requirements for electrical equipment for measurement, control, and laboratory use —
Part 1: General requirements
IEC 61310-1, Safety of machinery — Indication, marking and actuation — Part 1: Requirements for visual,
auditory and tactile signals
IEC 61310-2, Safety of machinery — Indication, marking and actuation — Part 2: Requirements for marking
IEC 61496-1, Safety of machinery — Electro-sensitive protective equipment — Part 1: General requirements
and tests
IEC 61496-2, Safety of machinery — Electro-sensitive protective equipment — Part 2: Particular requirements
for equipment using active opto-electronic protective devices (AOPDs)
ANSI/NFPA 86, Standard for Ovens and Furnaces
EN 378-1, Refrigerating systems and heat pumps — Safety and environmental requirements — Part 1: Basic
requirements, definitions, classification and selection criteria
EN 563, Safety of machinery — Temperatures of touchable surfaces — Ergonomics data to establish
temperature limit values for hot surfaces
EN 1127-1, Explosive atmospheres — Explosion prevention and protection — Basic concepts and
methodology
EN 1539, Dryers and ovens, in which flammable substances are released — Safety requirements
EN 1760-2, Safety of machinery — Pressure-sensitive protective devices — Part 2: General principles for the
design and testing of pressure-sensitive edges and pressure-sensitive bars
EN 12198-1:2000, Safety of machinery — Assessment and reduction of risks arising from radiation emitted by
machinery — Part 1: General principles
prEN 13023, Noise measurement methods for printing, paper converting, paper making machines and
auxiliary equipment — Accuracy grades 2 and 3
4 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
4.1
actuator
part of the actuating system to which an external actuating force is applied
[IEV 441-15-22]
NOTE 1 The actuator may take the form of a handle, knob, pushbutton, roller, plunger, etc.
NOTE 2 There are some actuating means that do not require an external actuating force but only an action.
NOTE 3 See also machine actuator (4.32).
4.2
alcohol dosing equipment
equipment for dosing the amount of alcohol in the dampening water of offset printing presses
4 © ISO 2003 — All rights reserved

4.3
armed condition
machine condition in which machine motion can be automatically initiated
NOTE Zero speed (4.88) may be considered to be an armed condition.
4.4
audible alarm
horn, bell or other distinctive audible warning device which, when sounded, indicates impending machine
motion
4.5
authorized person
person designated as such by plant management as having been trained in the following:
a) the task to be performed;
b) the function of the adjustments in the work zone;
c) proper operation of adjustments and controls;
d) all types of hazards in the area where the task is to be performed;
e) the application of equivalent, alternative protection to perform the task;
f) improper actions that can cause injury; and
g) the consequences of those improper actions
4.6
automatic plate clamping device
device for automatic or semi-automatic changing of printing plates
4.7
auxiliary devices for printing presses
devices used for the production process which are either built in or attached to the printing press
4.8
barrier guard
guard closing off access to an area containing one or more hazards
4.9
category 0 stop
stopping by immediate removal of power to the machine actuators (i.e. an uncontrolled stop)
[IEC 60204-1]
4.10
category 1 stop
controlled stop with power to the machine actuators available to achieve the stop and then removal of power
when the stop is achieved
[IEC 60204-1]
4.11
category 2 stop
controlled stop with power to the drive elements of the machines being maintained
[IEC 60204-1]
4.12
coating unit
coater
type of finishing machine for applying liquid substances (for example glue, varnish, ink) on substances made
of paper or similar material in a predetermined thickness; the thickness of the layer is determined by a doctor
blade (scraper) or by the gap between two rollers (metering gap)
4.13
continuous flow drying and curing device
device built into printing presses for drying and curing substrates after the printing process (for example by hot
air, IR or UV radiation)
4.14
crawl speed
continuous motion at a steady slow speed, and initiated by a momentary contact control
4.15
cylinder screen printing press
sheet-fed printing press where the substrate (sheet) is guided along the screen by a printing cylinder
4.16
digital printing press
printing press where the printing image is produced from data stored in digital form
EXAMPLE Exposing a photo-sensitive drum or film in the machine.
4.17
electrical hazard
source of potential injury or death from electric shock or burn
4.18
emergency stop device
manually actuated control device used to initiate an emergency stop function
[ISO 13850:1996]
4.19
emergency stop function
function initiated by a single human action that is intended to avoid injury to persons, damage to machinery or
damage to work in progress
4.20
enabling device
actuating device that needs to be operated in addition to at least one more actuator or device in order to start
a machine under hold-to-run control; machine movement is stopped as soon as one of the hold-to-run controls
or enabling devices is released
4.21
exposing equipment
machinery used for taking images by exposing photo-sensitive material such as printing plates or printing
forms
4.22
fixed guard
guard that is securely affixed by fasteners that require a tool(s) to gain access to a significant hazard
6 © ISO 2003 — All rights reserved

4.23
forms printing press
leporello printing press
machine for the production of continuous forms where paper webs printed with one or multiple colours are
leporello folded or wound onto a reel
NOTE In addition to the printing section, the machine consists of devices for punching, rema liners, cross perforation,
longitudinal perforation and leporello folding.
4.24
gravure press
machine consisting of a printing cylinder, an impression cylinder and an inking system, in which ink is applied
to the printing cylinder by an ink roll or spray, and the excess is removed by a doctor blade; the impression
cylinder, covered with a rubber composition, presses the substrate into contact with the ink in the cells of the
printing surface
4.25
guard
physical barrier that restricts access to a significant hazard
4.26
hazard zone
any area within and/or around machinery in which a person is exposed to risk of injury or damage to health
NOTE Adapted from ISO 12100-1.
4.27
hold-to-run control
control that starts and maintains machine motion only as long as the control is activated (see 5.5)
4.28
in-running nip
in-going nip
area created by either two rotating components that are rotating inward, or one rotating component rotating
toward an adjacent surface
See Figure 1.
a) Two counter- b) Two rolls rotating c) Two rolls rotating d) One rotating roll e) Belt, chain, and
rotating rolls at different speeds in the same and an adjacent fixed possibly a web
direction, but with object driving or being
different surface driven by a roll
properties (friction)
Figure 1 — In-running nips
4.29
inch
jog
motion condition requiring maintained activation of a hold-to-run control; motion will continue until the control
is released or until a pre-determined displacement has been reached (limited inch)
4.30
inch speed
speed at which the press is operating while in inch mode
4.31
infrequently used workplace
area where a function that is routine, repetitive, and integral to (but not necessarily during) production, but
done on an infrequent basis, is conducted
NOTE Examples of such activities include observation, refill of the ink pan, blanket change and plate change, access
to elevated sheet-fed presses, make-ready, minor servicing, jam clearing, etc.
4.32
machine actuator
power mechanism used to effect motion of a machine
[ISO 13850:1996]
4.33
maintained contact control
control that remains opened/closed after activation of the control
4.34
maintenance
operation that is usually performed when the machine is not available for production
EXAMPLE Examples of maintenance operations are repairing or replacing broken, worn or damaged parts;
performing lubrication; preventive servicing, etc. Maintenance is normally performed by qualified maintenance personnel,
or operators, who have been trained about the types of hazards in the area in which their tasks are to be performed and
about how these hazards can be avoided. When possible, this should be performed with energy isolated.
4.35
make-ready
tasks preceding a production run, such as adjusting ink controls for proper colour, plate alignment for proper
registration, adjusting pressures, measurement with quality control devices, etc.
4.36
manual control device
part of the actuating system to which a manual action is applied
NOTE Adapted from IEV 441-15-22.
4.37
mechanical hazard
source of potential injury to a person that is created by motion of machinery, components or material
4.38
mechanical hazard points
locations in the machines where persons can be injured by parts of machines or machine movement, such as
 tools of machines, or parts thereof;
 work pieces, or parts thereof; or
 materials being processed
8 © ISO 2003 — All rights reserved

4.39
momentary contact control
control that is opened/closed only during actuation of the control
4.40
motion control
control that initiates machine motion
4.41
motion control station
operator control station containing both an emergency stop and a motion initiation control
4.42
motion zone
area defined by any press component, or group of press components, that is driven directly by the press
system drive motor(s) or indirectly by the web
4.43
movable control station
control station that is permanently wired to the equipment, but can be moved within the confines of the
attached cable
4.44
movable guard
guard that does not require a tool to gain access to a significant hazard
4.45
newspaper printing presses
presses that are designed and built mainly for printing newspapers
4.46
nip guard
guard (nip bar, finger bar, finger guard) located at an in-going nip
4.47
non-motion zone
area defined by any press component, or group of press components that, due to press configuration, is not
driven by the press system drive motor(s) or the web
NOTE When the console is freestanding (not press-mounted), it is a non-motion zone.
4.48
non-operational press
press configured for functions other than delivering products, such as make-ready or wash-up
4.49
normal operation
condition that exists during set-up, make-ready, production and minor servicing/adjusting and cleaning
performed by operators; this does not include maintenance operations (see 4.34)
4.50
operating position
the location where normal operations (make-ready and other routine, repetitive tasks) requiring control of main
drive motor(s) are performed
4.51
operational press
press that is configured to deliver product, is composed of at least one motion zone, and may include non-
motion zones
4.52
operator control station
panel containing at least an emergency stop control
4.53
personnel warning lights
red and green lights used to indicate the ready, running and safe conditions of the printing press relative to
personnel safety
NOTE These lights are not the same as machine status lights.
4.54
pile turner
device for turning substrates and attached to sheet-fed printing presses in order to turn piles of printed paper
for further processing
NOTE An example of further process may be back printing in a second run.
4.55
portable control station
control station that can be disconnected from one location, moved to another location and be reconnected
4.56
positive mechanical action
·of a component on another componentÒ action in which the moving mechanical component inevitably moves
another component along with it, either by direct contact or by rigid elements
NOTE 1 This also applies to a component that prevents any movement of another component by virtue of its presence.
NOTE 2 When a mechanical component moves and thus allows another component to move freely (e.g. by gravity,
spring force, etc.), there is no positive mechanical action of the first component on the other component.
4.57
positive opening
achievement of contact separation as the direct result of a specified movement of the actuator through non-
resilient members
NOTE For example, not dependent upon springs.
4.58
powder spraying devices
devices for spraying powder onto the printed material on the delivery side of sheet-fed printing presses
4.59
pre-press machinery
machines and equipment for the production of master copies and/or printing plates
4.60
press system
printing press and a series of machines that supply substrate into and through the printing press and guide or
direct the substrate to a cutting, folding or delivery device that delivers the product to the last working station
integrated with the printing press control system
4.61
printing form
printing plate
base material that stores the image to be printed (pictures and/or text) and transfers ink on a substrate (such
as printing plates, printing cylinders, screen), thus printing the image
10 © ISO 2003 — All rights reserved

4.62
printing plate bending machine
machine for bending or folding printing plates before they are clamped in the printing press
4.63
printing table
table to hold the substrate to be printed during the printing process (as on certain types of screen printing
presses)
4.64
proofing press
machine for printing a small number of copies, generally used for assessing print quality before the printing
form is mounted in the machine, with manual feeding and delivery
4.65
raised workplace
workplace that is at least 0,5 m above access level
4.66
ready condition
condition in which machine motion can be operator initiated
4.67
reel rewinding device
that part of a machine used for rewinding the processed web-type material
4.68
reel turner
device for turning webs wound onto reels for easier handling, for example, for correct positioning of the reel
when feeding webs to printing presses
4.69
reel unwinding device
that part of a machine used for unwinding web-type material for processing
4.70
remote control
connection to the control station of a machine by use of an external communication link
4.71
routine and regular access
repetitive access to a hazard point that is required for manual feeding of a machine during normal production
activity
4.72
safe condition
condition in which movement of the main drive motor(s) (prime mover) of the motion zone is prevented
NOTE This condition may apply to the entire press system or to one or more motion zones. The safe condition exists
only when one or more stop/safe or emergency stop pushbuttons are latched in the depressed position.
4.73
screen frame
frame for taking up the printing screen
4.74
screen printing press
printing press using printing forms with woven material (screens) that partially allow ink to penetrate through
the material
4.75
separating elements
elements on feeders of sheets or blanks or similar materials that separate the individual sheets, blanks, etc.
4.76
sheet-fed press
machine for printing sheet-size substrates, including proofing presses, in which sheets may be fed by feeders
(automatic or manual), or from sheeters attached to unwinding units
4.77
significant hazard
potential source of severe or disabling injury, or death
NOTE This International Standard only addresses significant mechanical hazards.
4.78
smooth roller
cylinder
rotationally symmetric solid body with smooth surface; i.e. with grooves or elevations of a maximum of 4 mm
deep and with circumferential slots of a maximum of 8 mm in width with no sharp or cutting edges
See Figure 2.
Dimensions in millimetres
Figure 2 — Smooth roller/cylinder
4.79
status lights
lights that indicate machine process condition
NOTE These are not the same as personnel warning lights.
4.80
trip nip bar
a movable protective bar located at an in-going nip that when pushed activates the interlocked safety system
of the machine
4.81
two-hand control
safety device that consists of two manual control devices that must be operated simultaneously by a single
operator to initiate potentially hazardous machine motion
4.82
warning period
period during which machine motion is prevented, and a warning is given to personnel that machine motion is
about to occur
4.83
washing device for roller/cylinder
device integrated into the printing press for washing cylinders and rollers such as ink rollers, blanket cylinders,
printing cylinders, plate cylinders
12 © ISO 2003 — All rights reserved

4.84
washing equipment for printing forms
machines for washing printing forms outside the printing press
EXAMPLE An example would be screen washing equipment.
4.85
web-fed press
press in which a substrate passes through the printing couple, or couples, in a continuous form, as fed from a
roll
4.86
web-type material
web of paper, board, foil or similar material that is to be handled or processed
4.87
wireless control
using means other than physical connection for transmitting commands and signals between a machine
control system and the operator control station(s)
4.88
zero speed
condition of machine motion in which the drive control system is actively holding the machine at a position
NOTE 1 In this condition, machine movement is not discernible; however, machine movement can be initiated without
warning.
NOTE 2 Zero speed may be considered to be an armed condition (see 4.3).
5 Guarding of significant hazards
Guarding, consistent with operation of the machine, shall be provided in those areas where recognized
exposure to significant hazards exists to operators. Exposure to significant hazards is not considered to exist if,
during normal operation, the distance to the hazard complies with those specified in ISO 13852:1996.
Machinery shall be designed according to the principles of ISO 12100 (all parts) for hazards that are relevant,
but not significant, and that are not covered by this International Standard.
Machines should be designed to allow normal production operations such as make-ready, wash-up, operator-
performed maintenance or troubleshooting without machine motion. Where machine motion is required to
perform these functions, guards and safety devices shall provide protection against hazards or these
operations shall be carried out using a hold-to-run device as specified in 5.5.
5.1 Guards
5.1.1 Types of guards
For the purpose of this International Standard there are two types of guards, fixed and movable.
Guards that do not have to be opened frequently shall be interlocked or shall be fixed in such a way that their
removal necessitates the use of a tool, such as a key or wrench, designed to operate a fastener.
NOTE 1 An improvised tool, such as a coin or nail file, does not meet the requirements of this International Standard.
All movable guards shall be interlocked.
Guards that are designed to be opened, removed, and/or moved at least once per working shift, on an
average, during normal operation, removed for make-ready (set-up) operations, or permit access to a
hazardous area, with or without the use of a tool, shall also be interlocked.
NOTE 2 A typical shift is 8 h.
NOTE 3 An example of setting-up and other purposes for which guards and doors may be removed include:
 to supply the material to be processed;
 to change the format;
 to change tools;
 for make-ready; or
 for washing-up.
The interlock system shall operate as described in 5.4.1.
When the interlocked guard is open, one of the measures set out in 5.5 shall become effective.
Guards shall not create any additional significant hazards to personnel, and shall satisfy the requirements of
ISO 14120.
5.1.1.1 Automatic travel of movable guards
Automatic travel of movable guards shall not create any significant mechanical hazards.
NOTE This can be achieved, for example, by limiting the force of the guard movement. The following guidelines are
suggested:
a) 50 N or less where the likely contact surface of the guard is an edge or projection and there is no risk of cutting or
stabbing injuries; or
b) 150 N or less where the likely contact surface of the guard is a plane so that there is no risk of a crushing injury.
Higher values may be chosen based upon risk analysis.
5.1.1.2 Protection against gravity falls of guards
Guards that can be opened shall be safeguarded against gravity falls if this creates a risk of injury.
NOTE Examples of means that may be used include:
 devices for balancing the weight;
 pneumatic springs;
 devices that automatically hold the parts open;
 power-driven worm gear drives actuated by hold-to-run controls if the hazard points can be observed from the
position where the hold-to-run control is actuated; or
 ensuring that the centre of gravity of the guard in the open position is sufficiently far behind the axis of rotation.
Springs used for balancing the weight shall be designed such that no hazard shall result from failure of the
spring or movement of the guard. Compression-type springs are preferred. Springs shall not display any
permanent deformation, even after extensive use.
5.1.2 Guard distances and gaps
The safety distance between the guard and the in-running nip is measured at that point where the distance
between the rotating surfaces, or the rotating surface and a fixed surface, is 10 mm. See Figure 3. Safety
distances shall be as specified in ISO 13852:1996.
The design and construction of the barrier guard shall ensure that personnel cannot reach the hazard by
reaching up, over, under, around or through the barrier guard.
On guide rollers the safety distance shall be 120 mm, as specified is ISO 13854.
14 © ISO 2003 — All rights reserved

Dimensions in millimetres
Figure 3 — Measuring safety distance at in-running nips
5.1.2.1 Reaching upwards
If there is a low risk from the hazard zone when reaching upward, then the height of the hazard zone shall be
2 500 mm or more, as required by ISO 13852:1996.
If there is a high risk from the danger zone when reaching upward, then either the height of the danger zone
shall be 2 700 mm or more, or other safety measures shall be used.
5.1.2.2 Reaching over protective structures
If there is a low risk from a hazard zon
...