a practical guide to machine safeguarding€¦ · machine safeguarding standards and regulations 12...

Machine Safeguarding Standards and Regulations

12 Banner Engineering Corp. • Minneapolis, MN U.S.A. • bannerengineering.com • Tel: 763.544.3164

Intr

oduc

tion


Introduction

Machine safeguarding refers to therequirements, equipment and methods used

to protect people who operate or come in contactwith dangerous machines.

Machine safeguarding is a critical part of anysafety program and benefits workers,manufacturers and employers at several levels:

• It reduces lost work days due to injury(resulting in higher productivity),

• It minimizes liability for the employer, and

• It can demonstrate an employer’scompliance with safety standards to theappropriate regulatory agencies.

• OEMs who incorporate safeguarding intotheir machines enjoy a ready market fortheir easy-to-use, pre-integrated machines,coupled with reduced liability, because theycan control safety system integration.

While the benefits of safeguarding are obvious,developing a machine safeguarding strategy canbe daunting. Given the variety of machine designs,coupled with varying levels of operator andmaintenance personnel interaction andcompounded by the many standards andregulations to reference, machine safetyimplementation can easily overwhelm thoseinvolved in the process.

A Practical Guide to Machine Safeguarding


13Banner Engineering Corp. • Minneapolis, MN U.S.A. • bannerengineering.com • Tel: 763.544.3164

IntroductionMachine Safeguarding Standards and Regulations

National, Regional and International Standards Systems

Safety standards come under the heading ofinternational, regional and national standards

systems. The combination of standards andregulations that apply in each case will depend onthe goals of those responsible for machinesafeguarding. For instance, an OEM shippingmachinery to several countries may need toconsider international, national and regionalrequirements, while an employer safeguarding themachinery in a single plant may be moreconcerned with corporate specifications and localrequirements.

There are two main types of standards that dealwith machine safeguarding:

• Application standards, which deal withapplying safety devices to machinery, and

• Product-specific standards, which definehow safety devices themselves mustperform.

While the basic structure and principles of thestandards systems may be similar, they willusually have some important differences. Manystandards agencies are working toward uniformity,and some standards systems already have beenharmonized with one another.

Harmonization of Standards

In all areas of standardization – including machinesafety – standards systems continue to move

toward harmonization. Emerging nations embraceexisting international standards rather thandeveloping their own. Industrialized nationscontinue to align with or adopt standards from theinternational system. In the United States, ANSIencourages its members to evaluate equivalentinternational standards prior to drafting new ANSIstandards, and significant adoption andharmonization has taken place betweenorganizations such as UL, IEC and NFPA.Additionally, nationally recognized testinglaboratories (such as UL) have establishedreciprocal arrangements with other labs and

standards bodies throughout the world in order tosimplify the process of product certification forinternational markets. The result has been that ENstandards are accepted (often with little change) andrepublished as IEC standards. (One example is theprogression of EN50100 into IEC 1496 and finallyinto IEC61496-1, Safety of Machinery – Electro-Sensitive Protective Equipment.)

A major key to understanding the world of inter-national standards is to first understand the players.

The countries in the European Union (EU) havebeen developing standards for a number of years;the process was already in high gear well beforethe EU was a reality. As a result of their early andthorough coverage of the subject, Europeanstandards have had significant influence oninternational machine safety standards. In effect,when national systems and certificationorganizations harmonize with international safetystandards, they also are harmonizing with Europe.

The advantage is that users may now obtain safetyequipment from a variety of international sourcesthat are designed and certified to strict standards.But while much harmonization has already takenplace around the globe, it is important toremember that the “law of the land” in any nationmay well be different than the EN or IECstandards. Individual government requirementsmay cause confusion for those who install safetyproducts designed for an international market.



Intr

oduc

tion


United States Standards System Structure

Formal relationships between OSHA and ANSI (viaa Memorandum of Understanding) and UL

(through accreditation) create the primary machinesafety structure for the US.

In the US, standards regarding the use and designof personnel safety devices are regulated by theOccupational Safety and Health Administration(OSHA). Founded in 1970,this governmental bodydefines and enforcesrequirements for maintaining a safe workplaceenvironment. Prior to the existence of OSHA,industry relied upon voluntary industry consensusstandards developed by organizations such as the

American National Standards Institute(ANSI) and Underwriters Laboratories(UL). OSHA recognizes the voluntaryconsensus standards developed by USindustry through coordination with

ANSI, and grants accreditation to test laboratories,including UL. OSHA also encourages the use ofcertain standards developed by consensusstandards bodies and recognized test labs. Forinstance, OSHA requires “appropriate” guards tobe installed on a machine, but it does not developguard design or machine design standards. OSHAdoes not certify equipment, devices or installationsfor compliance.

ANSI (a private, non-profitorganization founded in1918) gave the US its firststandard relating specifically

to machine safety in the workplace. ANSI B11.1-1926, Mechanical Power Presses – SafetyRequirements for Construction Care and Use, isthe US precursor to all machine safety standardsdeveloped since. ANSI does not developstandards; it oversees standards development byvoluntary consensus bodies, such as theAssociation for Manufacturing Technology (AMT),the Robotic Industries Association (RIA) and theNational Fire Protection Association (NFPA). Whena standard meets ANSI requirements for industry

OSHAOSHA

R

consensus and content, ANSI adopts andpublishes it. Designing to comply with ANSI is acommon method of demonstrating productconformity, but is not mandatory. As is the casewith OSHA, third-party certification to ANSImachine tool standards is, for all practicalpurposes, non-existent.

While most United States machine safety andrelated standards are associated with OSHA andANSI, independently operated NationallyRecognized Test Laboratories(NRTL) also develop supportstandards. NRTLs are recognizedand accredited by OSHA for theirability to adequately test and certify products. Underwriters Laboratories (UL) has been mostactive in the development and adoption ofpertinent standards for safety device certification.

UL is a private, not-for-profit organization foundedin 1894 to test devices, systems and materials forhazards to life and property. UL developsstandards specific to types of devices. Thus,where ANSI is concerned with applications at themachine level, UL usually takes a narrower view,toward issues related to the manufacturer of aspecific item or device.

Each organization plays a specific role insupporting machine safety, and formallyrecognizes standards from the others. State andlocal codes in effect for the machine’s installationlocation must also be considered.

Unlike other national and regional standardssystems, the United States does not have anapproved entity that can certify fully integrated andinstalled systems for safety compliance. Theresponsibility of ensuring compliance falls to theemployer, installer and/or OEM.

The lines can appear to blur between OSHA (agovernment agency) and ANSI or UL (industryconsensus organizations). To simplify the roleeach organization plays today:




• OSHA is the enforcement agency that requiresemployers to provide a safe work environment.OSHA regulations direct employers to usemachine-level and device-level standards fromappropriate standards bodies.

• ANSI facilitates the development ofstandards that give guidance for applyingsafety at the machine level. The ANSI B11series standards cover a variety of machinetools types, including its first machinesafety standard, B11.1 Mechanical PowerPresses, originally drafted in 1922.

• UL develops and adopts standards relatingto performance and testing requirements ofsafeguarding devices.

Performance requirements for safeguardingdevices are distinctly different from those for otherindustrial electrical apparatus. Specifically, OSHAand ANSI historically have required safety systemsand devices to arrest hazardous motion even inthe event of a failure within the safety system ordevice. The most common method used toachieve this high level of performance is to designredundancy and self-checking functions into thesafety system or device.

United States Standards

The concept of control reliabilityis the very essence of personnelsafeguarding in the United States.

OSHA 1910, section 212 requires machineoperators and other employees in the area to beguarded from the hazardous action of machinery;further discussion in section 217 clarifies that this isthe employers’ responsibility. ANSI B11 standardsalso highlight the responsibility of the employer toprovide redundant, self-checking protection forthose who work around hazardous machinery.

Currently, the US has only a few specific designstandards in place for safety systems. UL is the onlyagency currently publishing safety product designstandards, most of which were developed in thepast few years. Most useful to manufacturers areUL 991 Tests for Safety-Related Controls Employing

Solid-State Devices, UL 61496-1 Standard forElectro-Sensitive Protective Equipment, Part 1:General Requirements, UL 61496-2 Standard forElectro-Sensitive Protective Equipment, Part 2:Particular Requirements for Equipment Using ActiveOpto-Electronic Protective Devices (AOPDs), and UL1998 Standard for Safety-Related Software. Inaddition, basic standard UL 508 Industrial ControlEquipment ensures that the device is electricallysafe from shock or fire hazard.

State and Federal Regulation – OSHA

Nationally, two OSHA regulations for machinesafeguarding (Title 29, Part 1910, sections 212and 217) recently appeared in a top-ten list ofmost-frequently-cited violations. Section 212addresses the general requirements for allmachines, while section 217 focuses on themechanical power press. Beyond this “law of theland,” a number of standards cover the applicationof safety equipment on specific types of machines.

Voluntary Consensus Standards – ANSI, NFPA

ANSI B11 standards provide the greatest depth ofinformation on the widest variety of machinery,with machine-specific safety standards (such asANSI B11.1, Mechanical Power Presses) to guidethe machine designer in establishing a safetystrategy. They are the best first source ofinformation about a point-of-operation applicationfor an employer.

One key standard for the application of safeguardingdevices is ANSI B11.19 Safeguarding whenReferenced by the Other Machine Tool Standards.ANSI B11.19 is a general guide to safeguarding andshould be considered a supplement to the specificmachine tool standards described above.

The Robotic Industries Association (RIA), togetherwith ANSI, developed ANSI/RIA R15.06, whichoutlines safety requirements for industrial robotsand robot systems. The standard is invaluable inproviding information in robotics applications.

The National Fire Protection Association (NFPA)has issued a general Electrical Standard forIndustrial Machinery (NFPA79), which also



Intr

oduc

tion

provides application information. NFPA79 hashistorically been used as the basis for many otherstandards worldwide, and is often used as anormative reference.

The European Union

The European community hascreated a useful harmonizedregional standards system in

support of its unification efforts. In the 1980s, keynations in Europe recognized their erodingposition in the global economy. Among thecontributing factors, goods could not move freelyacross borders within Europe and trade wasshifting to the United States and the Pacific Rim.The creation of the European Union (EU)addressed those concerns by implementing stepsto reduce European trade barriers and by creatinga harmonized standards system among membernations. This harmonized standards systemrequired foreign manufacturers to adapt productdesigns to comply with EU standards anddirectives (in effect, protecting the Europeaneconomy). Because the EU requires adherence totheir standards for machines imported into EUmember nations, a US firm building a piece ofpackaging equipment for European export mustsatisfy not only US requirements, but also theapplicable EN or IEC requirements.

Today, it is difficult to find products that are notlabeled with the CE mark, indicating compliance toEuropean requirements.

Machine Directive

No standard or piece of European legislation hashad more impact on machine safeguarding thanthe Machine Directive (98/37/EEC). In effect, theMachine Directive (MD) requires machines andsafeguarding devices shipped to EU countries tomeet essential health and safety requirements.

In many cases, the machine or safeguardingdevice must be third-party tested for complianceby an EU-approved entity (a “Notified Body”).European Directives are laws that establish generalrequirements; they are not specific standards that

support designers in their effort to comply. Aproduct is proved to be in compliance with theappropriate directives after it has been tested tospecific standards.

European Standards

For machine safety, the EU has developed acomprehensive system of standards that specifysafety principles and requirements. Under contractby the EU, two organizations, the Committee forStandardization (CEN) and the EuropeanCommittee for Electrotechnical Standardization(CENELEC), have been chiefly responsible forcoordinating the development of machine safetystandards. Four basic types of standards are usedto implement machine safety:

• Type A - Basic principles for all machines• Type B1 - Specific procedural or safety aspect• Type B2 - Specific safety device design• Type C - Specific machine requirements

A machine manufacturer may need all four typesof standards to implement safety into its design.For instance, a press manufacturer may use:

• EN 693 Hydraulic Presses as a machine (C)standard,

• EN 1050 Risk Assessment as a basic (A)standard,

• EN 954-1 Safety Related Parts of theControl System as a safety aspect (B1)standard, and

• EN 574 Two-Hand Control as a safetydevice (B2) standard.

Because the European machine safety standardsare so thorough, they have been routinely adoptedat international, national and corporate levels. Bothindustrialized and emerging nations have embraced



Introduction

harmonization with European standards to promoteworld trade and reduce duplication of effort.

(The prefix “pr” designates that a European Normis in its preliminary form.)

European Certification and Documentation

Product manufacturers shipping to the EU mustundergo a prescribed conformity assessmentprocess before affixing the CE mark. Thisconformity assessment may entail:

• Designing to satisfy a particular Directiveand a specific set of EU standards,

• Self-testing the product to ensurecompliance, and

• Assembling a Technical File withdocumentation that proves compliance.

The Technical File typically includes instructions,drawings, test data, certifications and procedures;the manufacturer or its authorized representativemust maintain it for review, should authorities everquestion product conformity. A nonconformingproduct can result in fines and/or forcedwithdrawal from the market.

Some products may require third-partycertification. Third-party certification requires, atminimum, an EU-approved Notified Body tovalidate the manufacturer’s Technical File. In somecases, the Notified Body will perform specifictesting before providing an EC-type examinationcertificate or certificate of adequacy. The MachineDirective requires many types of machinery andcomplex safety devices to be Notified Body-approved, and also requires a document (a“Declaration of Conformity”) to accompany all CE-marked products. (In the case of personnel safetydevices, such as safety light screens and safetymodules, mandatory certification is required.) TheDeclaration of Conformity lists the product’s make,type, standards applied and the manufacturer’sname and address.

The CE mark is a mandatoryadministrative mark that assures freemovement of products within member

nations of the EU. Basically a “ticket ofadmission,” this mark is a sign from themanufacturer that the requirements of relevantdirectives have been met, and that the requiredconformity assessment procedures have beencarried out.

International Standards

The topic of international safety standards isconfusing, because each country has its ownsafety guidelines.

Harmonized international standards benefitmanufacturers by allowing access to manymarkets with one design, while users enjoycompetitive products that meet uniform qualityand functional requirements – regardless of wherethey are made. Two international entities, theInternational Electrotechnical Committee (IEC) andthe International Standardization Organization(ISO), play a significant role in machine safety.Regional and national systems in eachparticipating market can influence internationalstandards development through formalrelationships. In the United States, thisinvolvement is coordinated by ANSI through itsTechnical Advisory Group (TAG), supervised bythe United States National Committee (USNC) andInternational Advisory Committee (IAC). Similarly,CEN and CENELEC coordinate European Unionparticipation at the international level.



Intr

oduc

tion


Safety System Performance

The performance integrity requirements forsafety system controls are different from those

used in production and quality system controls. Inmany cases, the safety control system (includingcomponents such as safety devices, relays,actuators and the wiring between them) mustdefault to a safe state in the event of failure(s)within the safety control system.

To accomplish the high integrity requirements ofsafety system design, redundancy and self-checkingfunctions are incorporated for back-up and to detectcomponent failures that may occur. Failures mayinclude shorted or open wiring circuits, welded orshorted circuit components, power failures,electrical or magnetic disturbances, or stuck valves.Depending on the level of risk associated with themachine or operation, an appropriate level of safetycontrol circuit performance must be incorporatedinto the design. Standards that detail safety systemperformance levels include ANSI/RIA R15.06 -1999, Safety Requirements for Industrial Robotsand Robot Systems and EN 954-1 Safety RelatedParts of Control Systems.

Safety Circuit Integrity Levels

Safety control circuits have been segmented intocategories, depending on their ability to maintain

their integrity in the event of failure(s). The mostrecognized standard detailing machine safety systemdesign integrity levels is ISO 13849-1 (EN 954-1)Safety Related Parts of Control Systems, whichestablishes five levels: the lowest, Safety Category Bto the highest, Safety Category 4.

In the United States, only one well-defined level ofsafety system integrity has been defined: controlreliability. Typically, both ANSI and OSHA haveassociated control reliability requirements with thepoint of operation of machines, where operatorsfeed and remove parts. Control reliability typicallyincorporates redundant control and self-checkingcircuitry to maintain a safe working environment.Redundancy ensures that a single failure cannotprevent the safe stopping of the machine, and self-checking ensures that a safety critical fault thatdoes occur is detected so the safety system canreact properly.

Because a Safety Category 4 application typicallyrequires the use of both redundancy and self-checking, it is often equated to the US standard ofcontrol reliability. One major difference must benoted, however: in a Safety Category 4 application,the requirement is to detect a fault at – or before –the next demand on the system. Control reliabilityallows the fault detection during the next demandon the system, as long as the system can stillsafely stop the hazardous motion. Thus, a SafetyCategory 4 application will always meet therequirements of control reliability, but the reverse isnot necessarily true.

If an application meets the guidelines for a lowerlevel of safety by EN definitions, those devices maynot meet legal requirements in the United States.Recently, however, ANSI/RIA R15.06 - 1999, SafetyRequirements for Industrial Robots and RobotSystems has detailed both risk assessment andmultiple levels of safety system integrity, the lowestreferred to as a Simple system and the highest acontrol reliable system.




The following general descriptions of safety circuitintegrity levels are not specific to any standard. Thegeneral rule: with increased risk of injury comes ahigher demand on safety system integrity.

Basic: May use non-safety-rated componentsdesigned to withstand the environment in which theywill be placed and integrated in accordance withrelevant standards. Provision for redundancy is notrequired; the system may fail to danger in the eventof a single fault within the system.

Single Channel: Safety-rated components are usedin conjunction with proven safety principles anddesigns. Provision for redundancy is not required;the system may fail to danger in the event of a singlefault within the system.

Single Channel with Monitoring: Safety-ratedcomponents are used in conjunction with a periodiccheck of the system at suitable intervals. Theperiodic check may be automatically or manuallyperformed during normal operation and at start-up.Normal operation is allowed if faults remainundetected. If a single unsafe fault is detected, thesystem will either default to a safe state or indicatethat an unsafe condition exists.

Dual Channel: This redundant system does not failto danger if a single fault occurs, because thesecond independent channel maintains the ability toarrest dangerous motion. While it is always good fora system to detect failures immediately, this may not

MACHINESTOP

SIMPLEDEVICE

StopCommand

MACHINESTOP

SAFE-GUARDING

DEVICE

Safety StopCommand

MACHINESTOP

SAFE-GUARDING

DEVICEMonitoring

Signal

Safety StopCommand

be practical, due to limitations in the technology orcomponents. If a critical fault goes undetected, asecond unrelated fault and its resultant loss of safetyfunction could still occur.

To further increase the safety of a dual-channelsafety system, diverse redundancy is employed. In adiverse-redundant system, the second independentchannel is different from the first (for example,normally open switches in the first channel, normallyclosed in the second).

Dual Channel with Monitoring: Redundancy andfully integrated checking functions, used together,provide this high level of safety system designintegrity. No single failure can cause the loss of thesafety function and any fault is detected immediatelyor at the next demand on the system. Once a safety-critical fault is detected within the system, a safestate is maintained until the failure is corrected.Because the single fault is detected and a safe stateis achieved quickly, the likelihood of multipleunrelated faults in both channels causing a failure todanger is statistically remote.

The method for monitoring safety systems oftendepends on the components used within the system.For example, because some mechanical devices,such as relays or safety interlock switches, can notbe actively monitored for unsafe faults duringmachine operation, a deliberate testing or checkingprocedure must be executed to verify appropriateresponse.

MACHINESTOP

SAFE-GUARDING

DEVICE

RedundantSafety StopCommands

MonitoringSignal

MACHINESTOP

SAFE-GUARDING

DEVICE

RedundantSafety StopCommands



Intr

oduc

tion


Risk Assessment

The rule of thumb in the U.S. for determiningthe required level of safeguarding has

historically been to provide the highest possiblelevel, wherever an identified hazard exists. InEurope and other markets, a risk assessmentprocess is used to determine the level of safetyprotection needed for a given application.

Risk assessment is an established process withmany uses, including the evaluation of machineryhazards. Specific procedures include Fault TreeAnalysis (FTA) and Failure Mode and Effect Analysis(FMEA). For machine safety, risk assessment isused to identify, document and eliminate or reducehazards in a particular machine or process.Standards that detail risk assessment includeANSI/RIA R15.06 - 1999, Safety Requirements forIndustrial Robots and Robot Systems, ANSI B11:TR3 Risk Assessment and Risk Reduction, and ISO14121 (EN 1050), Principles of Risk Assessment.EN 1050 and EN 954-1 standards outline theprocess of risk assessment and specify categoriesof safety equipment.

To decide the required level of safety, a riskassessment considers such factors as the severityof possible injury, the frequency with whichexposure to that injury can take place, and thepossibility of the worker avoiding the injury.

Risk estimation weighs such factors as theanticipated tasks performed by all personnel; theirknowledge, training and experience; and thepossibility that they can defeat safety measures orignore safety procedures. Once problem areas areidentified and safety measures (procedures,safeguards, training and warnings) are proposed,the solution must be evaluated to determine if therisk has been eliminated or reduced to anacceptable level. Depending on the hazard’s risklevel, the reliability and performance integrity ofthe safety system and all its components (devices,wiring and actuators) may be evaluated.

Conclusion

Determining how to address the safeguardingrequirements for any particular machine

design will depend on several factors. Thesefactors may include:

• What modes of operation the machine willbe used in,

• How operators and other personnel willinteract with the machine,

• How the machine controls function, and • The level of severity a particular hazardrepresents.

Once problem areas and machinelimitations are identified, the selection ofappropriate guarding techniques can becontemplated. Because of increased

uniformity among systems of safetystandards around the globe, the decision-makingprocess continues to become easier to under-stand. And because of increased understanding ofsafety principles and requirements, the world maybecome a safer place in which to work.

!

SEVERITY

PROBABILITY

Frequency and duration of exposure

Probability that a hazardous event will occur

Possibility of avoiding or minimizing harm

Degree of possible harm



Introduction

U.S. Application StandardsSOURCES

ANSI B11 Documents

American National StandardsInstitute11 West 42nd StreetNew York, NY 10036Telephone: (212) 642-4900

-or-

Safety DirectorAMT – The Association forManufacturing Technology7901 Westpark DriveMcLean, VA 22102Telephone: (703) 893-2900

ANSI/RIA DocumentsObtain from ANSI (above) or:

Robotics Industries Association900 Victors Way, P.O. Box 3724Ann Arbor, MI 48106Telephone: (734) 994-6088

NFPA Documents

National Fire Protection Association1 Batterymarch ParkP.O. Box 9101Quincy, MA 02269-9101Telephone: (800) 344-3555

OSHA Documents

Superintendent of DocumentsGovernment Printing OfficeP.O. Box 371954Pittsburgh, PA 15250-7954Telephone: (202) 512-1800

EN and IEC Standards

Global Engineering Documents15 Inverness Way EastEnglewood, CO 80112-5704Phone: (800) 854-7179Fax: (303) 397-2740

BS Documents

British Standards Association2 Park StreetLondon W1A 2BSEnglandTelephone: 011-44-908-1166

ANSI B11.1 Mechanical Power Presses

ANSI B11.2 Hydraulic Power Presses

ANSI B11.3 Power Press Brakes

ANSI B11.4 Shears

ANSI B11.5 Iron Workers

ANSI B11.6 Lathes

ANSI B11.7 Cold Headers and ColdFormers

ANSI B11.8 Drilling, Milling, and BoringMachines

ANSI B11.9 Grinding Machines

ANSI B11.10 Metal Sawing Machines

ANSI B11.11 Gear Cutting Machines

ANSI B11.12 Roll Forming and RollBending Machines

ANSI B11.13 Single- and Multiple-SpindleAutomatic Bar and Chucking Machines

ANSI B11.14 Coil Slitting Machines/Systems

ANSI B11.15 Pipe, Tube, and ShapeBending Machines

ANSI B11.16 Metal Powder CompactingPresses

ANSI B11.17 Horizontal Extrusion Presses

ANSI B11.18 Machinery and MachineSystems for the Processing of Coiled Strip,Sheet, and Plate

ANSI B11.19 Performance Criteria forSafeguarding

ANSI B11.20 Manufacturing Systems/Cells

ANSI B11.21 Machine Tools Using Lasers

ANSI B11.22 Numerically ControlledTurning Machines

ANSI B11.23 Machining Centers

ANSI B11.24 Transfer Machines

ANSI/RIA R15.06 Safety Requirements forIndustrial Robots and Robot Systems

NFPA 79 Electrical Standard for IndustrialMachinery

OSHA Documents listed are part of:Code of Federal Regulations Title 29, Parts1900 to 1910

OSHA 29 CFR 1910.212 GeneralRequirements for (Guarding of) All Machines

OSHA 29 CFR 1910.147 The Control ofHazardous Energy (lockout/tagout)

OSHA 29 CFR 1910.217 (Guarding of)Mechanical Power Presses

OSHA Regulations

ISO/TR 12100-1 & -2 (EN 292-1 & -2)Safety of Machinery – Basic Concepts,General Principles for Design

ISO 13852 (EN 294) Safety Distances . . . Upper Limbs

ISO 13850 (EN 418) Emergency StopDevices, Functional Aspects – Principles forDesign

ISO/DIS 13851 (EN 574) Two-HandControl Devices – Functional Aspects– Principles for Design

ISO 13853 (prEN 811) Safety Distances . . . Lower Limbs

ISO 13849 (EN 954-1) Safety-RelatedParts of Control Systems

ISO/DIS 13855 (EN 999) The Positioningof Protective Equipment in Respect toApproach Speeds of Parts of the Human Body

ISO 14121 (EN 1050) Principles of RiskAssessment

ISO 14119 (EN 1088) Interlocking DevicesAssociated with Guards – Principles forDesign and Selection

IEC/EN 60204-1 Electrical Equipment ofMachines Part 1: General Requirements

IEC/EN 61496 Electro-sensitive ProtectionEquipment

IEC 60529 Degrees of Protection Providedby Enclosures

IEC/EN 60947-5-1 Low Voltage Switchgear– Electromechanical Control Circuit Devices

IEC/EN 60947-1 Low Voltage Switchgear – General Rules

European Standards