ISO-14118-2000.pdf

Reference number ISO 14118:2000(E) ©ISO 2000 INTERNATIONAL STANDARD ISO 14118 First edition 2000-09-15 Safety of machinery Prevention of unexpected start-up Sécurité des machines Prévention de la mise en marche intempestive ISO 14118:2000(E) 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. 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CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyrightiso.ch Web www.iso.ch Printed in Switzerland ii© ISO 2000 All rights reserved ISO 14118:2000(E) © ISO 2000 All rights reservediii Contents Foreword.iv Introduction.v 1Scope 1 2Normative references1 3Terms and definitions .1 4General requirements2 4.1Isolation and energy dissipation2 4.2Other means to prevent unexpected unintended start-up3 5Means for isolation and energy dissipation3 5.1Devices for isolation from power supplies .3 5.2Locking securing devices 3 5.3Devices for stored-energy dissipation or restraint containment.4 5.4Verification .5 6Measures, other than isolation and energy dissipation, to prevent unexpected start-up.5 6.1Design strategy5 6.2Measures to prevent accidental generation of start commands6 6.3Measures to prevent accidental start commands resulting in unexpected start-up6 6.4Automatic monitoring of the category 2 stopped condition.9 Annex A (informative) Examples of tasks which can require the presence of persons in danger zones 10 Annex B (informative) Signalling and warning.11 Bibliography12 ISO 14118:2000(E) iv© ISO 2000 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 3. 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 International Standard may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. International Standard ISO 14118 was prepared by Technical Committee ISO/TC 199, Safety of machinery. ISO 14118 has been prepared to be a harmonized standard in the sense of the Machinery Directive of the European Union and associated regulations of the European Free Trade Association (EFTA). It is in relationship with, in particular, the essential safety requirements expressed in subclauses 1.2.3, 1.2.6, 1.2.7, 1.6.3 and 1.6.4 of annex A of ISO/TR 12100-2:1992. ISO 14118:2000(E) © ISO 2000 All rights reservedv Introduction Keeping a machine in a stopped condition while persons are present in danger zones is one of the most important conditions of the safe use of machinery and hence one of the major aims of the machine designer and machine user. In the past, the concepts of “operating machine“ and “stopped machine“ were generally unambiguous; a machine was: ?operating when its movable elements, or some of them, were moving; ?stopped when its movable elements were at rest. Machine automation has made the relationship between “operating“ and “moving“ on the one hand and “stopped“ and “at rest“ on the other hand, more difficult to define. Automation has also increased the potential for unexpected start-up, and a significant number of accidents have occurred where machines, stopped for diagnostic work or corrective actions, started up unexpectedly. Hazards other than mechanical hazards generated by movable elements (e.g. from a laser beam) also need to be taken into account. The risk assessment relating to the presence of persons in a danger zone of a stopped machine needs to take into account the probability of an unexpected start-up of the hazard-generating elements. This International Standard provides machine designers and machinery safety standard technical committees with a survey of built-in measures which can be used to prevent unexpected start-up. INTERNATIONAL STANDARDISO 14118:2000(E) © ISO 2000 All rights reserved1 Safety of machinery Prevention of unexpected start-up 1Scope This International Standard specifies designed-in means aimed at preventing unexpected machine start-up (see 3.2) to allow safe human interventions in danger zones (see annex A). This International Standard applies to unexpected start-up from all types of energy source, i.e.: ?power supply, e.g. electrical, hydraulic, pneumatic; ?stored energy due to, e.g., gravity, compressed springs; ?external influences, e.g. from wind. 2Normative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this International Standard. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. However, parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain registers of currently valid International Standards. ISO/TR 12100-1:1992, Safety of machinery Basic concepts, general principles for design Part 1: Basic terminology, methodology. ISO/TR 12100-2:1992, Safety of machinery Basic concepts General principles for design Part 2: Technical principles and specifications. ISO 14121, Safety of machinery Principles for risk assessment. IEC 60204-1:1997, Electrical equipment of industrial machines Part 1: General requirements. EN 1070, Safety of machinery Terminology. 3Terms and definitions For the purposes of this International Standard, the terms and definitions given in EN 1070 and the following apply. 3.1 start-up machine start-up change from rest to motion of a machine or of one of its parts NOTEThe definition includes functions other than motion, e.g. switch-on of a laser beam. ISO 14118:2000(E) 2© ISO 2000 All rights reserved 3.2 unexpected unintended start-up any start-up caused by: ?a start command which is the result of a failure in, or an external influence on, the control system; ?a start command generated by inappropriate action on a start control or other parts of the machine as, e.g., a sensor or a power control element; ?restoration of the power supply after an interruption; ?external/internal influences (gravity, wind, self-ignition in internal combustion engines, etc.) on parts of the machine. NOTEStart-up by the normal operation of automatic machinery is not to be considered as unintended start-up, but can be considered to be unexpected from the point of view of the operator. Prevention of accidents in this case involves the use of safeguarding measures (see ISO/TR 12100-2:1992, clause 4). 3.3 isolation and energy dissipation procedure which consists of all of the four following actions: a)isolating (disconnecting, separating) the machine (or defined parts of the machine) from all power supplies; b)locking (or otherwise securing), if necessary (for instance in large machines or in installations), all the isolating units in the “isolated“ position; c)dissipating or restraining containing any stored energy which may give rise to a hazard. NOTEEnergy considered in c) above may be stored in e.g.: ?mechanical parts continuing to move through inertia; ?mechanical parts liable to move by gravity; ?capacitors, accumulators; ?pressurized fluids; ?springs. d)verifying by using a safe working procedure that the actions taken according to a), b) and c) above have produced the desired effect. 4General requirements 4.1Isolation and energy dissipation Machines shall be provided with means intended for isolation and energy dissipation (see clause 5), especially with a view to major maintenance, work on power circuits and decommissioning in accordance with the essential safety requirement expressed in ISO/TR 12100-2:1992, annex A, 1.6.3. ISO 14118:2000(E) © ISO 2000 All rights reserved3 4.2Other means to prevent unexpected unintended start-up If the use of isolation and energy dissipation is not appropriate (e.g. for frequent short interventions), the designer shall provide, according to the risk assessment in accordance with ISO 14121, other measures (see clause 6) to prevent unexpected start-up. Additional means such as signalling and/or warning may be appropriate (see annex B). NOTE 1Examples of tasks which can require the presence of persons in danger zones are given in annex A. NOTE 2According to ISO/TR 12100-1:1992, 5.7.1, the designer should determine as completely as possible the different machine operating modes and the need for the presence of persons in danger zones. Appropriate safety measures can then be provided. These measures should prevent operators from being induced to use hazardous operating modes and hazardous intervention techniques caused by technical difficulties in the use of the machine (see ISO/TR 12100-1:1992, 3.12). 5Means for isolation and energy dissipation 5.1Devices for isolation from power supplies 5.1.1Isolation devices shall: ?ensure a reliable isolation (disconnection, separation); ?have a reliable mechanical link between the manual control and the isolating element(s); ?be equipped with clear and unambiguous identification of the state of the isolation device which corresponds to each position of its manual control (actuator). NOTE 1For electrical equipment, a supply disconnecting device complying with IEC 60204-1:1997, 5.3 “Supply disconnecting (isolating) device“ meets this requirement. NOTE 2Plug and socket systems (for electrical supplies), or their pneumatic, hydraulic or mechanical equivalents, are examples of isolating devices with which it is possible to achieve a visible and reliable discontinuity in the power supply circuits. For electrical plug/socket combinations, see IEC 60204-1:1997, 5.3.2 d). NOTE 3For hydraulic and pneumatic equipment, see also EN 982:1996, 5.1.6 and EN 983:1996, 5.1.6. 5.1.2The location and number of isolation devices will be determined by the configuration of the machine, the need for the presence of persons in danger zones and the risk assessment. Each isolation device shall be readily identifiable as to which machine, or part of it, it isolates (e.g. by durable marking where necessary). NOTEFor electrical equipment of machinery, see also IEC 60204-1:1997, 5.4. 5.1.3When, during isolation of the machine, certain circuits have to remain connected to their power supply in order, e.g., to hold parts, protect information or provide local lighting, special means shall be provided to ensure operator safety. NOTESuch means include enclosures which can be opened only with a key or a special tool, warning labels and/or warning lights. 5.2Locking securing devices The isolation devices shall be capable of being locked or otherwise secured in the “isolated“ position. NOTELocking devices may not be necessary when a plug/socket combination is used and the plug can be kept under immediate supervision of the person present in the danger zone. ISO 14118:2000(E) 4© ISO 2000 All rights reserved Locking devices include: ?facilities to apply one or more padlocks; ?trapped-key interlocking devices (see ISO 14119:1998, annex E), one of the locks of which is associated with the manual control actuator of the isolating device; ?lockable housings or enclosures. Locking devices are not required when reconnection cannot endanger persons. 5.3Devices for stored-energy dissipation or restraint containment 5.3.1General 5.3.1.1Devices for stored-energy dissipation or restraint containment shall be incorporated into the machine where stored energy can give rise to a hazard. NOTESuch devices include brakes intended to absorb kinetic energy of moving parts, resistors and relevant circuitry to discharge electrical capacitors, valves or similar devices to depressurize fluidic accumulators (see EN 982:1996, 5.1.6 and EN 983:1996, 5.1.6). 5.3.1.2When dissipation of stored energy would excessively reduce the ability of the machine to be used, additional means shall be incorporated to reliably restrain or contain the remaining stored energy. 5.3.1.3The devices for energy dissipation or restraint containment should be selected and arranged so that: ?dissipation or restraint containment results from the isolation of the machine (or part of it); ?the energy dissipation process does not give rise to hazardous situations. 5.3.1.4The necessary procedures for energy dissipation or restraint containment shall be described in the instruction handbook of the machine or in warnings on the machine itself. 5.3.2Mechanical elements When mechanical elements can give rise to a hazardous situation ?by virtue of their mass and position (e.g. unbalanced, or raised, or in any situation where they could move under the effect of gravity), ?or as a result of the action upon them of spring load (whatever this “spring“ is made of), means shall be provided to bring them to the lowest energy state (e.g. lowest position or spring-relaxed) either by the usual machine manual controls or by devices specifically designed and identified (marked) for t