This glossary is a work in progress, assembled from a variety of sources, mostly standards, but a few websites and online dictionaries as well. We have provided the original sources wherever possible. If you feel the source is incorrect, of if a term is incorrectly referenced, please let us know!
We have included some definitions just because we thought they were interesting — many of those from the Ford Motor Company fall into that group but could also be useful for describing machinery and hazards.
Want to add something that’s missing? Send it to us, including the full source citation, and we will gladly add it!
Additional Official Sources
There are three additional sources of definitions, standard graphics and other information that you may not know about:
- ISO Online Browsing Platform – The Online Browsing Platform is a publicly available service from ISO that permits users to search ISO Standards, Collections, Graphical Symbols, Terms and Definitions, and Country Codes at no charge.
- IEC Electropedia – Also known as the International Electrotechnical Vocabulary, or IEC 60050, this online service gives users direct access to the most current terms and definitions in the electrotechnical sector.
- IEC Glossary – A compilation of electrotechnical terminology in English and French extracted from the “Terms and Definitions” clause of IEC publications (those issued since 2002). In some cases, terms and definitions have also been collected from earlier publications (e.g. from TC 37, 77, 86 and CISPR). The database contains some 65 000 items drawn from 3 000 publications, with new ones being added on a continuous basis.
- acceptable risk
- risk that may be readily allowed by affected persons, based on an based on an informed decision Note 1: Accepted risks may be subject to periodic monitoring and reduction, particularly when the values of society change, or when new information regarding the risk becomes available, thus making previously acceptable risks unacceptable. Note 2: Where residual risk is thought to be extremely low, risks are often accepted based on a presumption of safety rather than an informed decision about a particular risk. MS101 Note: This definition is a proposed definition that has not been officially published, thus the lack of citation. :-)See ‘tolerable risk’
- (as applied to equipment) – Admitting close approach; not guarded by locked doors, elevation, or other effective means.
- (as applied to wiring methods) – Capable of being removed or exposed without damaging the building structure or finish or not permanently closed in by the structure or finish of the building.
- Readily (Readily Accessible) – Capable of being reached quickly for operation, renewal, or inspections without requiring those to whom ready access is requisite to actions such as to use tools, to climb over or remove obstacles, or to resort to portable ladders, and so forth.
National Electrical Code. NFPA 70. National Fire Protection Association, Batterymarch Park. 2014
- Access time (time for access to a danger zone)
- The time taken to access the hazardous machine parts after initiation of the stop command by the interlocking device, as calculated on the basis of an approach speed the value of which may be chosen, for each particular case, taking into account the parameters given in prEN 999 ‘Safety of machinery — The positioning of protective equipment in respect of approach speeds of parts of the human body’. EN 1088, §3.9
- acknowledged rule of technology
- technical provision acknowledged by a majority of representative experts as reflecting the state of the art
NOTE A normative document on a technical subject, if prepared with the coöperation of concerned interests by consultation and consensus procedures, is presumed to constitute an acknowledged rule of technology at the time of its approval.
ISO Guide 2:2004, §1.5
- separate part of an interlocking device which transmits the state of the guard (closed or not closed) to the actuating system NOTE 1 A guard mounted cam, a key, a shaped tongue, a reflector, a magnet, an RFID tag are examples of actuators. NOTE 2 See also Annex A to E. NOTE 3 See examples of actuators in Figure 2. ISO 14119, §3.12 [See also Coded Actuator]
- Actuating System
- part of the interlocking device which transmits the position of the actuator and changes the state of the output system NOTE 1 A roller plunger, a cam linkage system, an optical, inductive or capacitive sensor are examples of an actuating system. NOTE 2 See examples of actuating systems in Figure 2. ISO 14119, §3.14
- Adequate risk reduction
- the achievement of a risk level unlikely to give rise to a situation that could result in harm to any person. See ‘acceptable risk’.
- Adjustable barrier guard
- a fixed guard that is adjustable as a whole or that incorporates adjustable parts. The adjustment to the guard remains fixed during operation. CSA Z432-04, §3 [See Guard]
- See Live
- “As Low As Reasonably Practicable”. The ALARP Principle comes from UK OHS law:
“The main tests that are applied in regulating industrial risks are very similar to those we apply in day to day life. They involve determining:
- whether a given risk is so great or the outcome so unacceptable that it must be refused altogether; or
- whether the risk is, or has been made, so small that no further precaution is necessary; or
- if a risk falls between these two states, that it has been reduced to the lowest level practicable, bearing in mind the benefits flowing from its acceptance and taking into account the costs of any further reduction. The injunction laid down in safety law is that any risk must be reduced so far as reasonably practicable, or to a level which is ‘as low as reasonably practicable’ (ALARP principle).”
The Tolerability of Risk from Nuclear Power Stations, UK Health and Safety Executive, HMSO OPSI, London, 1992
- The quantity or amount of energy produced by a vibrating component (G‑force). An extreme vibration has a high amplitude. A mild vibration has a low amplitude. [See Intensity] Ford Motor Company
- Switching function, for which a sensor produces two output signals (and therefore two output functions): “normally open” and “normally closed” (NC – normally closed contact). When an object is detected, both outputs are switched to their opposite state. [Ed. note: translated from French and paraphrased for clarity.] Balluff Company
- At height
- access positions located 2.5 m above the surrounding surface or landing. CSA Z432-04, §3
- Acceptable to the authority having jurisdiction. National Electrical Code. NFPA 70. National Fire Protection Association, Batterymarch Park. 2014
- Authority Having Jurisdiction (AHJ)
- An organization, office, or individual responsible for enforcing the requirements of a code or standard, or for approving equipment, materials, an installation, or a procedure.
Informational Note: The phrase “authority having jurisdiction,” or its acronym AHJ, is used in NFPA documents in a broad manner, since jurisdictions and approval agencies vary, as do their responsibilities. Where public safety is primary, the authority having jurisdiction may be a federal, state, local, or other regional department or individual such as a fire chief; fire marshal; chief of a fire prevention bureau, labor department, or health department; building official; electrical inspector; or others having statutory authority. For insurance purposes, an insurance inspection department, rating bureau, or other insurance company representative may be the authority having jurisdiction. In many circumstances, the property owner or his or her designated agent assumes the role of the authority having jurisdiction; at government installations, the commanding officer or departmental official may be the authority having jurisdiction.
National Electrical Code. NFPA 70. National Fire Protection Association, Batterymarch Park. 2014
- Barrier (fixed distance) guard
- a fixed guard that does not completely enclose the hazard but that reduces access by virtue of its physical dimensions and its distance from the hazard. CSA Z432-04, §3 [See Guard]
- Low frequency or low pitched noise often accompanied by a vibration. [Also refer to Drumming.] Ford Motor Company
- Buffet / Buffeting
- Strong noise fluctuations caused by gusting winds. An example would be wind gusts against the side glass. Ford Motor Company
- process conducted with the sole intention of stabilizing parameters
- Note 1 to entry: Burn-in is an accelerated conditioning by operating the item under its operating electrical load at an elevated temperature, which is generally the maximum operating temperature that does not exceed the thermal rating of the device. IEC 60050, 192 – 12-01
- A low-pitched sound like that from a bee. Often a metallic or hard plastic humming sound. Also describes a high-frequency vibration. Vibration feels similar to an electric razor. Ford Motor Company
- assembly of one or more conductors and/or optical fibres, with a protective covering and possibly filling, insulating and protective material [IEV 151 – 12-38] [IEC 62491:2008, 3.2]
- CE Marking
- CE Marking is the symbol as shown on the top of this page. The letters “CE” are the abbreviation of French phrase “Conformité Européene” which literally means “European Conformity”.
The term initially used was “EC Mark” and it was officially replaced by “CE Marking” in the Directive 93/68/EEC in 1993. “CE Marking” is now used in all EU official documents.
- CE Marking on a product is a manufacturer’s declaration that the product complies with the essential requirements of the relevant European health, safety and environmental protection legislation, in practice by many of the so-called Product Directives.
- CE Marking on a product indicates to governmental officials that the product may be legally placed on the market in their country.
- CE Marking on a product ensures the free movement of the product within the EFTA & European Union (EU) single market (including totally 30 EEA* countries), and
- CE Marking on a product permits the withdrawal of the non-conforming products by EEA customs and enforcement/vigilance authorities.
- Product certification is the process of evaluating a (usually electrical) product against the requirements of a Certification Standard, using standardized safety test methods in an accredited Certification Laboratory. This process is typically called a “certification scheme” in the product certification industry. At the end of the process, products that successfully meet the requirements are permitted to be marked with the Certification Body’s trademark under license. Ongoing factory audits are required to ensure that the products produced do not vary from the samples submitted for testing. Product Certification is typically used for series production of 200 or more units annually. See Product Certification. Wikipedia, [online].For production volumes below 200 units per year, Field Evaluation is normally the most appropriate approach to compliance.
- Third-party attestation related to products, processes, systems or persons
Note 1 to entry: Certification of a management system is sometimes also called registration.
Note 2 to entry: Certification is applicable to all objects of conformity assessment except for conformity assessment bodies themselves, to which accreditation is applicable.
ISO/IEC 17000:2004, 5.5
Chatter — A pronounced series of rapidly repeating rattling or clicking sounds. Ford Motor Company
Chirp — A short-duration, high-pitched noise associated with a slipping drive belt.Ford Motor Company
Chuckle— A repetitious, low-pitched sound. A loud chuckle is usually described as a knock.Ford Motor Company
Click — A sharp, brief, non-resonant sound, similar to actuating a ball point pen. Ford Motor Company
Clonk — A hydraulic knocking sound. Sound occurs with air pockets in a hydraulic system. Also described as hammering. Ford Motor Company
Clunk — A heavy or dull, short-duration, low-frequency sound. Occurs mostly on a vehicle that is accelerating or decelerating abruptly. Also described as a thunk. Ford Motor Company
Code of practice — document that recommends practices or procedures for the design, manufacture, installation, maintenance or utilization of equipment, structures or products
NOTE A code of practice may be a standard, a part of a standard or independent of a standard. ISO Guide 2:2003, §3.5
- low level coded actuator — coded actuator for which the number of code versions available need to be 1 to 9;
- medium level coded actuator — coded actuator for which the number of code versions available need to be 10 to <= 1 000;
- high level coded actuator — coded actuator for which the number of code versions available need to be > 1 000.
ISO 14119, §3.13 [See also Actuator]
- procedures prior, or related, to handing over a product ready for putting into service, including final acceptance testing; handing over of drawings, instructions for operation, maintenance and repair; if necessary, instructing personnel IEC 62079:2001, 3.2
- procedure by which a system is formally accepted by the purchaser. ISO 4414:2010, 3.1
- procedures prior, or related , to the handing over of a product ready for putting into service, including final acceptance testing, the handing over of all documentation relevant to the use of the product and, if necessary, instructing personnel IEC 82079 – 1, 2012, §3.3
common sense = knowledge + experience + attention + exposure
Where any element is missing or insufficient, there can be no common sense.
Wynand Serfontaine and others on the LinkedIN Safety Engineering Network
MS101 NOTE: It is important to recognize that the preceding definition will result in a different outcome for every individual to whom it is applied, since every individual has different knowledge, experience, attention (focus) and exposure to the specific hazard being considered. This illustrates the problem with trying to use the ‘common-sense’ approach in risk control. As Mark Twain once said, “The problem with common sense is that it’s not too common.”
Alternate Definition – Common sense is that unique body of knowledge and experience related to hazards commonly experienced in day-to-day life by an individual. D. Nix, 2005
Complementary protective measures— Protective measures that are neither inherently safe design measures, nor safeguarding (implementation of guards and/or protective devices), nor information for use may have to be implemented as required by the intended use and the reasonably foreseeable misuse of the machine. Such measures shall include, but not be limited to,
- emergency stop;
- means of rescue of trapped persons; and
- means of energy isolation and dissipation.
CSA Z432-04 (R2009), §22.214.171.124.3
See also “Protective Measure”
See also ISO 12100:2010, §6.3.5
Compliance – “Compliance” is used to describe the action of doing what is required (e. g. an organization “complies” by making something or by fulfilling a regulatory requirement). ISO/IEC 17000:2004, §3 [See Conformity]
- Mechanical. The components that carry (transmit) a vibration frequency from the originator to the reactor. Ford Motor Company
- Bare. A conductor having no covering or electrical insulation whatsoever. National Electrical Code. NFPA 70. National Fire Protection Association, Batterymarch Park. 2014
- Covered. A conductor encased within material of composition or thickness that is not recognized by this Code as electrical insulation. National Electrical Code. NFPA 70. National Fire Protection Association, Batterymarch Park. 2014
- Insulated. A conductor encased within material of composition and thickness that is recognized by this Code as electrical insulation. National Electrical Code. NFPA 70. National Fire Protection Association, Batterymarch Park. 2014
- conductor (of a cable) – part of a cable which has the specific function of carrying current
[IEV 461 – 01-01] [IEC 62491:2008, 3.1] See also core.
conformity — fulfillment of specified requirements
Note 1 to entry: The term “conformance” is synonymous but deprecated.
IEC 82079 – 1, 2012, §3.5
- outcome of an event (126.96.36.199) affecting objectives
NOTE 1 An event can lead to a range of consequences.
NOTE 2 A consequence can be certain or uncertain and can have positive or negative effects on objectives.
NOTE 3 Consequences can be expressed qualitatively or quantitatively.
NOTE 4 Initial consequences can escalate through knock-on effects.
Risk management — Vocabulary. ISO Guide 73, §188.8.131.52. ISO International Organization for Standardization. 2009.
- outcome of an occurrence of a particular set of circumstances
Note 1 to entry: There can be more than one consequence from one event. IEC 82079 – 1, 2012, §3.6
[See also “severity”]
Conformity – “Conformity” means fulfillment of a requirement. Specified requirements may be stated in normative documents as regulations, standards and technical specifications. ISO/IEC 17000:2004, §3
- The circuit of a control apparatus or system that carries the electric signals directing the performance of the controller but does not carry the main power current. National Electrical Code. NFPA 70. National Fire Protection Association, Batterymarch Park. 2014
- (of a machine) circuit used for the control, including monitoring, of a machine and the electrical equipment. Safety of machinery — Electrical equipment of machines — Part 1: General Requirements, §3.8. IEC 60204 – 1. International Electrotechnical Commission (IEC). Geneva. 2006.
Control Guard – See “Interlocking guard with a start function”
core – assembly comprising a conductor with its own insulation (and screens if any)
[IEV 461 – 04-04] [IEC 62491:2008, 3.3] See also: conductor
Cracks — A mid-frequency sound, related to squeak. Sound varies with temperature conditions. Ford Motor Company
Creak — A metallic squeak. Ford Motor Company
Current-carrying — See “Live”
Cycle — The process of a vibrating component going through a complete range of motion and returning to the starting point. [See Frequency] Ford Motor Company
Danger zone — the zone around the machine (front, back, sides, top, and bottom) where a hazard is created by the motion of the machine components. CSA Z432-04, §3 See ‘Hazard Zone’.
- A unit of measurement, referring to sound pressure level, abbreviated dB. Ford Motor Company
- a unit used to measure the intensity of a sound or the power level of an electrical signal by comparing it with a given level on a logarithmic scale. New Oxford American Dictionary
- a logarithmic unit of sound intensity; 10 times the logarithm of the ratio of the sound intensity to some reference intensity. Wordnet 3.0 2006
defeat – action that makes interlocking devices inoperative or bypasses them with the result that a machine is used in a manner not intended by the designer or without the necessary safety measures. ISO 14119
NOTE 1 This definition includes the removal of switches or actuators using tools that are needed for the intended use of the machine or that are readily available (screw drivers, wrenches, hexagon keys, pliers).
NOTE 2 Readily available objects for substitute actuation can be:
- screws, needles, sheet-metal pieces;
- objects in daily use such as keys, coins, adhesive tape, string and wire;
- spare keys for the trapped-key interlocking devices;
- spare actuators.
direct contact – electric contact of persons or animals with live parts
[IEC 60050 – 195: 1998, 195 – 06-03] EN 60519 – 1:2006, 3.1
[Also see “Positive Drive”]
direct opening action (of a contact element) – achievement of contact separation as the direct result of a specified movement of the switch actuator through non-resilient members (for example not dependent upon springs) IEC 60947 – 5‑1, Ed. 3, 2009 § K.2.2
[See also “Direct Drive” “Force Guided”, “Mechanically Linked”, “Positively Guided”, “Positive Drive”]
direct opening travel – travel from the beginning of actuation of the actuator and the position when the direct opening action of the opening contacts is completed IEC 60947 – 5‑1, Ed. 3, 2009 § K.2.3
direct opening force (or moment) – actuation force, or actuating moment for a rotary control switch, applied to the actuator for the direct opening action IEC 60947 – 5‑1, Ed. 3, 2009 § K.2.4
Disconnecting Means – A device, or group of devices, or other means by which the conductors of a circuit can be disconnected from their source of supply. National Electrical Code. NFPA 70. National Fire Protection Association, Batterymarch Park. 2014.
Drone — A low-frequency, steady sound, like a freezer compressor. Also described as a moan. Ford Motor Company
Drumming — A cycling, low-frequency, rhythmic noise often accompanied by a sensation of pressure on the ear drums. Also described as a low rumble, boom or rolling thunder. Ford Motor Company
emergency control — control function that brings a system to a safe condition ISO 4414:2010, 3.2
- A function that is intended to avert harm or to reduce existing hazards to persons, machinery, or work in progress. CSA Z432-04, §3.
- The operation of a circuit that overrides all other robot controls, removes drive power, causes all moving parts to stop, and removes power from other hazardous functions present in the safeguarded space but does not cause additional hazards. ANSI RIA 15.06 – 99, §3.11
- The operation of a circuit that overrides all other robot controls, removes drive power, causes all moving parts to stop, and removes power from other hazardous functions present in the safeguarded space but does not cause additional hazards. CSA Z434-03, §3.
Emergency switching off device — Manually actuated control device used to switch off the supply of electrical energy to all or a part of an installation where a risk of electric shock or another risk of electrical origin is involved. IEC 60204 – 1, 2005, §3.18
- a device that is designed to initiate a machine action or allow the flow of energy to a machine. CSA Z432-04, §3
- additional manually operated device used in conjunction with a start control and which, when continuously actuated, allows a machine to function ISO 12100:2010 §3.28.2
- A manually operated device which when continuously activated, permits motion. ANSI RIA R15.06 – 1999 §3.12
See ‘deadman control’.
- a mechanical device that physically prevents the transmission or release of energy, including but not limited to the following: a manually operated electrical circuit breaker; a disconnect switch; a manually operated switch by which the conductors of a circuit can be disconnected from all ungrounded supply conductors; a line valve; a block; and other devices used to block or isolate energy (push-button selector switches and other control-type devices are not energy-isolating devices). CSA Z460 2005
- A mechanical device that physically prevents the transmission or release of energy, including but not limited to the following: a manually operated electrical circuit breaker, a disconnect switch, a manually operated switch by which the conductors of a circuit can be disconnected from all ungrounded supply conductors and, in addition, no pole can be operated independently; a line valve; a block; and any similar device used to block or isolate energy. ANSI Z244.1 – 2003
- A device that physically prevents the transmission or release of energy, including but not limited to the following: A manually operated electrical circuit breaker; a disconnect switch; a manually operated switch by which the conductors of a circuit can be disconnected from all ungrounded supply conductors, and, in addition, no pole can be operated independently; a line valve; a block; and any similar device used to block or isolate energy. Push buttons, selector switches and other control circuit type devices are not energy isolating devices. 29 CFR 1901.147
See also “Hazardous Energy”
equipotential bonding – provision of electric connections between conductive parts, intended to put them at a substantially equal potential
[IEC 60050 – 195:1998, 195 – 01-10, modified], EN 60519 – 1:2011, 3.14
equipotential bonding system (EBS)interconnection of conductive parts providing equipotential bonding between those parts
NOTE If an equipotential bonding system is earthed, it forms part of an earthing arrangement.
[IEC 60050 – 195:1998, 195 – 02-22], en60519‑1:2011. 3.15
- (conductive part) conductive part of electrical equipment, which can be touched and which is not live in normal operation, but which can become live under fault conditions
[IEC 60050 – 826:2004, 826 – 12-10, modified], EN 60519 – 1:2011, 3.16
- (as applied to live parts) Capable of being inadvertently touched or approached nearer than a safe distance by a person.
Informational Note: This term applies to parts that are not suitably guarded, isolated, or insulated. National Electrical Code. NFPA 70. National Fire Protection Association, Batterymarch Park. 2014.
- (as applied to wiring methods) On or attached to the surface or behind panels designed to allow access. National Electrical Code. NFPA 70. National Fire Protection Association, Batterymarch Park. 2014.
extraneous conductive part – conductive part not forming part of the electrical installation and liable to introduce an electric potential, generally the electric potential of a local earth
[IEC 60050 – 826:2004, 826 – 12-11], EN 60519 – 1:2011, 3.17
- Fail-safe standstill monitor
- A fail-safe device which provides a signal that may be used to release locked guards, or control a safe access condition when a machine has come to a standstill. In the case of a fault, e.g., a defective rotation sensor or internal fault in the standstill monitoring device, the fail-safe standstill monitor fails into a safe state. See also “standstill monitor”. Adapted from Schmersal Canada Ltd.
- Field Evaluation (FE)
- Field Evaluation is a service provided by accredited inspection bodies to bridge the gap between uncertified equipment and a code-compliant installation acceptable to the Authority Having Jurisdiction (AHJ). Field evaluation is used in North America to permit small volume (1 – 200 units per year) production of electrical products to be evaluated by qualified inspectors and “field labelled” to show compliance with the National Electrical Code (NFPA 70) in the US, or the Canadian Electrical Code (CSA C22.1) in Canada. Inspection is conducted by an accredited Inspection Body. In the US, these are known as Nationally Recognized Testing Laboratories (NRTL), and in Canada as Accredited Inspection Bodies.
- FIT (unit) — Failure in Time
- 1 FIT = 1 x 10-9 failures/h. The FIT unit finds its origin in reliability engineering for the semiconductor industry. In datasheets and certificates for SIL rated equipment (mainly sensors, actuators and the like intended for use in the process industry according to IEC 61511) the unit FIT is commonly used for presenting failure rate data (lambda values). The FIT unit was developed to ease writing and reading the information. Most instruments specifically designed for process industry SIL applications have failure rates in the range of 1 x 10-9/h to 3 x 10-6/h. When expressed using FIT these values are written as 10 to 3000 FIT. This is easier to read, and easier to compare datasheets for instruments, etc. Bert Brouwers, LinkedIn.com, IEC 62061 and ISO 13849 machinery functional safety group, accessed 28-Sep-2011.
- Fixed guard
- a guard kept in place (i.e., closed or attached to a fixed surface) either permanently (e.g., by welding) or by means of fasteners (screws, nuts, etc.), making removal or opening impossible without using tools. CSA Z432-04, §3
- [See also “Guard”]
- Mid to high intermittent sound due to air flow. Similar to a flag flapping in the wind. Ford Motor Company
- Force Guided, forced contacts
- deprecated. See “Mechanically Linked”.
- Alternate Definition – Force Guided Relays And Mirror Contact Relays
- Force-guided (or positively-guided) relays have contacts that are mechanically interlocked such that two contacts on the relays will not contradict each other, even in the event that the relay welds. Force-guided relays have contacts that are force-guided/mechanically linked conforming to IEC60947‑1 – 1 as required for use in safety-related control systems.
- The mirror contact relays conform to EN 60947 – 4‑1 by using a combination of the relay block and the auxiliary contact block.
- “Force Guided Relays And Mirror Contact Relays”, [online]. OMRON STI. Accessed: 6‑Jun-2013. Available: http://www.sti.com/force-guided-relays/.
- The rate at which a cycle occurs within a given time. [See Cycle] Ford Motor Company
- number of events (184.108.40.206) or outcomes per defined unit of time
- NOTE Frequency can be applied to past events (220.127.116.11) or to potential future events, where it can be used as a measure of likelihood (18.104.22.168) / probability (22.214.171.124).
- Risk management — Vocabulary. Risk management — Vocabulary. ISO Guide 73, §126.96.36.199. ISO International Organization for Standardization. 2009.
- Functional Safety
- Part of the overall safety relating to the EUC and the EUC control system that depends on the safety-related systems and external risk reduction facilities operating correctly in response to their inputs.
Out of control — Why control systems go wrong and how to prevent failure. HSG 238.
- Functional safety is part of the overall safety that depends on a system or equipment operating correctly in response to its inputs. The term “safety-related” is used to describe systems that are required to perform a specific function or functions to ensure risks are kept at an accepted level. Such functions are, by definition, safety functions. Two types of requirements are necessary toachieve functional safety:
- safety function requirements (what the function does;) and
- safety integrity requirements (the likelihood of a safety function being performed satisfactorily).
The safety function requirements are derived from the hazard analysis and the safety integrity requirements are derived from a risk assessment. The higher the level of safety integrity, the lower the likelihood of dangerous failure. “Functional safety of electrical/electronic/programmable electronic safety-related systems – Part 0: Functional safety and IEC 61508”, IEC/TR 61508 – 0 Edition 1, International Electrotechnical Commission, Geneva, 2005
- system that performs in a way that does not present an unreasonable risk of injury to operators or bystanders
ISO 25119 – 1:2010, §3.20
- Part of the overall safety relating to the EUC and the EUC control system that depends on the safety-related systems and external risk reduction facilities operating correctly in response to their inputs.
- functional safety concept
- entire collection of safety-related functions and interactions necessary to achieve a desired behaviour
Note 1 to entry: It is developed during the concept phase of the safety life cycle.
ISO 25119 – 1:2010, §3.21
- functional safety requirement
- requirement for a safety-related function of the E/E/PES system
ISO 25119 – 1:2010, §3.22
G‑force — The additional load or weight produced in an object during acceleration. When measuring the level or amplitude of a vibration without sound, the unit G is added to associate the force of the vibration to gravity. This is similar to measuring the weight of an object, which is also a function of gravity. Ford Motor Company
Gravelly Feel — A grinding or growl in a component, similar to the feel experienced when driving on gravel. Ford Motor Company Grind — An abrasive sound, similar to using a grinding wheel, or rubbing sand paper against wood. Ford Motor Company
Ground — The earth. National Electrical Code. NFPA 70. National Fire Protection Association, Batterymarch Park. 2014.
See also International electrotechnical vocabulary (IEV). IEC 60050, [online]. International Electrotechnical Commisssion (IEC). Geneva.
Ground Fault — An unintentional, electrically conductive connection between an ungrounded conductor of an electrical circuit and the normally non – current-carrying conductors, metallic enclosures, metallic raceways, metallic equipment, or earth. National Electrical Code. NFPA 70. National Fire Protection Association, Batterymarch Park. 2014.
Grounded (Grounding) — Connected (connecting) to ground or to a conductive body that extends the ground connection. National Electrical Code. NFPA 70. National Fire Protection Association, Batterymarch Park. 2014.
Grounded, Solidly — Connected to ground without inserting any resistor or impedance device.National Electrical Code. NFPA 70. National Fire Protection Association, Batterymarch Park. 2014.
Grounded Conductor — A system or circuit conductor that is intentionally grounded. National Electrical Code. NFPA 70. National Fire Protection Association, Batterymarch Park. 2014.
Grounding Conductor, Equipment (EGC) — The conductive path(s) that provides a ground-fault current path and connects normally non – current-carrying metal parts of equipment together and to the system grounded conductor or to the grounding electrode conductor, or both.
Informational Note No. 1: It is recognized that the equipment grounding conductor also performs bonding.
Informational Note No. 2: See 250.118 for a list of acceptable equipment grounding conductors.
National Electrical Code. NFPA 70. National Fire Protection Association, Batterymarch Park. 2014.
- Cover or equip (a part of a machine) with a device to protect the operator. Oxford New American Dictionary
- A part of machinery specifically used to provide protection by means of a physical barrier. Depending on its construction, a guard may be called a casing, screen, door, enclosing guard, etc. CSA Z432-04, §3
- A barrier that prevents exposure to an identified hazard. E3.22 Sometimes referred to as a “barrier guard.” ANSI B11.19 2003, §3.22
- Electrical. Covered, shielded, fenced, enclosed, or otherwise protected by means of suitable covers, casings, barriers, rails, screens, mats, or platforms to remove the likelihood of approach or contact by persons or objects to a point of danger. National Electrical Code. NFPA 70. National Fire Protection Association, Batterymarch Park. 2014.
[See Fixed guard]
[See Movable guard]
- a device that is designed to hold the guard closed and locked until the hazard has ceased. CSA Z432-04, §3
- Device intended to lock a guard in the closed position and linked to the control system so that:
- the machine cannot operate trntil the guard is closed and locked;
- the guard remains locked until the risk has passed.
EN 1088:1996, §3.4
- device intended to lock a guard in the closed position and linked to the control system. ISO 14119
NOTE The term hazard can be qualified in order to define its origin or the nature of the expected harm (e.g. electric shock hazard, crushing hazard, cutting hazard, toxic hazard, fire hazard, drowning hazard).
ISO Guide 51:99
Hazard groups (ISO)
- relevant hazard – Hazard which is identified as being present at or associated with the machine.Note 1 to entry: A relevant hazard is identified as the result of one step of the process described in ISO 12100:2010, Clause 5.Note 2 to entry: This term is included as basic terminology for type B- and type C‑standards.Safety of machinery — General principles for design — Risk assessment and risk reduction. ISO 12100, 3.7. ISO International Organization for Standardization. Geneva. 2010
- significant hazard – Hazard which has been identified as relevant and which requires specific action by the designer to eliminate or to reduce the risk according to the risk assessment.Note 1 to entry: This term is included as basic terminology for type B- and type C‑standards.Safety of machinery — General principles for design — Risk assessment and risk reduction. ISO 12100, 3.8. ISO International Organization for Standardization. Geneva. 2010
- Any electrical, mechanical, hydraulic, pneumatic, chemical, nuclear, thermal, gravitational, or other energy that can harm personnel. CSA Z460 2005
- Any electrical, mechanical, hydraulic, pneumatic, chemical, nuclear, thermal, gravity or other energy that could cause injury to personnel. ANSI Z244.1 – 2003, 2.10
See also “Energy Source”
- Circumstance in which people, property or the environment are exposed to one or more hazards ISO Guide 51:99
- A set of circumstances that may give rise to harm to a person. CSA Z432-04, §3
hazardous event — event that can cause harm NOTE A hazardous event can occur over a short period of time or over an extended period of time. ISO 12100:2010 §3.9
hazardous situation— circumstance in which a person is exposed to at least one hazard NOTE The exposure can result in harm immediately or over a period of time. ISO 12100:2010 §3.10
hazard zone— danger zone any space within and/or around machinery in which a person can be exposed to a hazard ISO 12100:2010, §3.12
- A unit of measure used to describe noise and vibration concerns expressed in cycles per second. [See Cycle and Frequency] Ford Motor Company
- the SI unit of frequency, equal to one cycle per second.The New Oxford American Dictionary
- n. [from the German physicist Heinrich Hertz.] A unit of frequency equal to one cycle per second; it is abbreviated Hz. It is commonly used to specify the frequency of radio waves, and also the clock frequencies in digital computers. For these applications, kilohertz and megahertz are the most commonly used units, derived from hertz. The Collaborative International Dictionary of English
- n. the unit of frequency; one hertz has a periodic interval of one second. Wordnet 3.0
Hiss — Steady, high-frequency noise. Vacuum leak sound. Ford Motor Company
Hoot — A steady, low-frequency tone, sounds like blowing over a long neck bottle. Ford Motor Company
Howl — A mid-range frequency noise between drumming and whine. Also described as a hum. Ford Motor Company
Hum — Mid-frequency steady sound, like a small fan motor. Also described as a howl. Ford Motor Company
hierarchy of controls — ranking of measures taken to prevent or reduce hazard exposure according to effectiveness. Measures are ordered from the most effective measures that eliminate hazards to the least effective measures that may achieve only limited risk reduction. Based on University of Southern Queensland (USQ), Human Resources – Glossary. Accessed 24-Feb-2011
HMI — See Human-Machine Interface.
hold-to-run control device — a control device that is designed to permit movement of machinery as long as the control is held in a set position. Once released, this device automatically returns the machine to the stop position. CSA Z432-04, §3
Human-Machine Interface — This is where people and technology meet. This people/ technology intercept can be as simple as the grip on a hand tool or as complex as the flight deck of a jumbo jet. ISA | Terminology, accessed 3‑Mar-11.
- Industrial Control Panel
- An assembly of two or more components consisting of one of the following:
- power circuit components only, such as motor controllers, overload relays, fused disconnect switches, and circuit breakers;
- control circuit components only, such as push buttons, pilot lights, selector switches, timers, switches, and control relays;
- a combination of power and control circuit components. These components, with associated wiring and terminals, are mounted on, or contained within, an enclosure or mounted on a sub panel. The industrial control panel does not include the controlled equipment.
National Electrical Code. NFPA 70. National Fire Protection Association, Batterymarch Park. 2014.
- Industrial robot
- an automatically controlled, reprogrammable multi-purpose manipulator programmable in three or more axes, which may be either fixed in place or mobile for use in industrial automation applications. CSA Z434-03, §3 [See Robot]
- Industrial robot system
- equipment that includes the robot(s) (hardware and software), consisting of the manipulator power supply and control system, the end-effector(s), and any other associated machinery and equipment within the safeguarded space. CSA Z434-03, §3
- Ingoing Pinch Point
- An ingoing pinch point is the point at which any part of a person’s body, such as fingers or hand, is likely to be drawn between a rotating machine member and another rotating or fixed member and be injured.
E2.11 Ingoing Pinch Point. Examples are two gears in mesh, a belt and pulley, or a wheel and partial guard. ANSI B11.8 – 1983 (R1999), §2.11
Also see “Pinch Point”
- In Sight From (Within Sight From, Within Sight)
- Where this Code specifies that one equipment shall be “in sight from,” “within sight from,” or “within sight of,” and so forth, another equipment, the specified equipment is to be visible and not more than 15 m (50 ft) distant from the other. National Electrical Code. NFPA 70. National Fire Protection Association, Batterymarch Park. 2014.
- Instruction (for use)
- information by the producer of a product for the safe and efficient use of the product IEC 62079:2001, 3.6
- information provided by the supplier of a product to the user, containing all the necessary provisions to convey the actions to be performed for the safe and efficient use of the product
Note 1 to entry: Instructions for use of a single product comprise one or more documents .
[SOURCE: ISO/IEC Guide 14:2003, definition 2.8, modified] IEC 82079 – 1, 2012, §3.19
- Intended use
- exhaustive range of functions or foreseen applications defined and designed by the supplier of the product
Note 1 to entry: Functions or applications not listed by the supplier are excluded from the intended use of the product.
Note 2 to entry: Additional or modified functions or applications resulting from modifications not sanctioned by the supplier of the product are excluded from the intended use.
IEC 82079 – 1, 2012, §3.20
[see also “reasonably foreseeable misuse”]
- The physical quality of sound that relates to the strength of the vibration (measured in decibels). The higher the sound’s amplitude, the higher the intensity and vice versa. [See Amplitude.] Ford Motor Company
- An interlock is a feature that makes the state of two mechanisms or functions mutually dependent. It may be used to prevent undesired states in a finite-state machine and may consist of any electrical, electronic, or mechanical devices or systems. In most applications, an interlock is used to help prevent a machine from harming its operator or damaging itself by preventing one element from changing state due to the state of another element, and vice versa.
- En.wikipedia.org. (2017). Interlock (engineering). [online] Available at: https://en.wikipedia.org/wiki/Interlock_(engineering) [Accessed 9 Aug. 2017].
- Interlocked barrier guard
- a fixed or movable guard attached and interlocked in such a manner that the machine tool will not cycle or will not continue to cycle unless the guard itself or its hinged or movable section encloses the hazardous area. CSA Z432-04, §3 [See Guard]
- Interlocking device (interlock)
- Mechanical, electrical or other type of device, the purpose of which is to prevent the operation of machine elements under specified conditions (generally as long as a guard is not closed). EN 1088:96, §3.1
- mechanical, electrical or other type of device, the purpose of which is to prevent the operation of hazardous machine functions under specified conditions (generally as long as a guard is not closed) ISO 12100:2010, 3.28.1
- Interlocking guard
- Guard associated with an interlocking device, so that:
- the hazardous machine functions ‘covered’ by the guard cannot operate until the guard is closed;
- if the guard is opened while the hazardous machine functions are operating, a stop instruction is given;
- when the guard is closed, the hazardous machine functions ‘covered’ by the guard can operate, but the closure of the guard does not by itself initiate their operation.
NOTE. In English ‘stop signal’ and ‘stop command’ are synonyms for ‘stop instruction’. In German, ‘Stop-Signal’ and ‘Stop-Befehl’ are synonyms for ‘Halt-Befehl’. In French ‘ordre d’arret’ is an all-encompassing term. EN 1088:96, §3.2
- guard associated with an interlocking device so that, together with the control system of the machine, the following functions are performed:
- the hazardous machine functions “covered” by the guard cannot operate until the guard is closed;
- if the guard is opened while hazardous machine functions are operating, a stop command is given;
- when the guard is closed, the hazardous machine functions “covered” by the guard can operate. The closure of the guard does not by itself start the hazardous machine functions. ISO 12100:2010, 3.27.4
- Guard associated with an interlocking device, so that:
- Interlocking guard with guard locking
- Guard associated with an interlocking device and a guard locking device so that:
- the hazardous machine functions ‘covered’ by the guard cannot operate until the guard is closed and locked;
- the guard remains closed and locked until the risk of injury from the hazardous machine functions has passed;
- when the guard is closed and locked, the hazardous machine functions ‘covered’ by the guard can operate, but the closure and locking of the guard do not by themselves initiate their operation.
- interlocking guard with a start function (control guard)
- special form of an interlocking guard which, once it has reached its closed position, gives a command to initiate the hazardous machine function(s) without the use of a separate start control. NOTE ISO 12100:2010, 188.8.131.52.5 gives detailed provisions regarding the condition of use. ISO 12100:2010, 3.27.6
- (electrically) instructed person
- person adequately advised or supervised by electrically skilled persons to enable him or her to perceive risks and to avoid hazards which electroheating installations can create (operating and maintenance staff)
[IEC 60050 – 826:2004, 826 – 18-02, modified], EN 60519 – 1:2011, 3.7
- Isolated (as applied to location)
- Not readily accessible to persons unless special means for access are used. National Electrical Code. NFPA 70. National Fire Protection Association, Batterymarch Park. 2014.
Knock — A heavy, loud, repetitious sound, like a knock on the door. Ford Motor Company
Key Performance Indicator (KPI) — A Key Performance Indicator is a measurable value that demonstrates how effectively a company is achieving key business objectives. Organizations use KPIs at multiple levels to evaluate their success at reaching targets. High-level KPIs may focus on the overall performance of the business, while low-level KPIs may focus on processes in departments such as sales, marketing, HR, support and others. klipfolio.com
NOTE 1 In risk management terminology, the word “likelihood” is used to refer to the chance of something happening, whether defined, measured or determined objectively or subjectively, qualitatively or quantitatively, and described using general terms or mathematically [such as a probability (184.108.40.206) or a frequency (220.127.116.11) over a given time period].
NOTE 2 The English term “likelihood” does not have a direct equivalent in some languages; instead, the equivalent of the term “probability” is often used. However, in English, “probability” is often narrowly interpreted as a mathematical term. Therefore, in risk management terminology, “likelihood” is used with the intent that it should have the same broad interpretation as the term “probability” has in many languages other than English.
Risk management — Vocabulary. ISO Guide 73, §18.104.22.168. ISO International Organization for Standardization. 2009
Listed — Equipment, materials, or services included in a list published by an organization that is acceptable to the authority having jurisdiction and concerned with evaluation of products or services, that maintains periodic inspection of production of listed equipment or materials or periodic evaluation of services, and whose listing states that either the equipment, material, or service meets appropriate designated standards or has been tested and found suitable for a specified purpose.
Informational Note: The means for identifying listed equipment may vary for each organization concerned with product evaluation, some of which do not recognize equipment as listed unless it is also labeled. Use of the system employed by the listing organization allows the authority having jurisdiction to identify a listed product.
National Electrical Code. NFPA 70. National Fire Protection Association, Batterymarch Park. 2014.
Live — electrically connected to a source of voltage difference, or electrically charged so as to have a voltage different from that of the earth; the term may be used in place of the term “current-carrying”, where the intent is clear, to avoid repetition of the longer term. CSA SPE-1000:99, §2
Live Parts — Energized conductive components. National Electrical Code. NFPA 70. National Fire Protection Association, Batterymarch Park. 2014.
- placement of a lock or tag on an energy-isolating device in accordance with an established procedure, thereby indicating that the energy-isolating device is not to be operated until removal of the lock or tag in accordance with an established procedure. CSA Z460, 2005
- a mechanical means of locking that uses an individually keyed lock to secure an energy-isolating device in a position that prevents energization of a machine, equipment, or a process. CSA Z460
- The placement of a lockout device on an energy isolating device, in accordance with an established procedure, ensuring that the energy isolating device and the equipment being controlled cannot be operated until the lockout device is removed. 29 CFR 1910.147
- A positive means such as a lock that secures an energy isolating device in a position that prevents the energizing of a machine, equipment or process. ANSI Z244.1 – 2003
- A device that utilizes a positive means such as a lock, either key or combination type, to hold an energy isolating device in the safe position and prevent the energizing of a machine or equipment. Included are blank flanges and bolted slip blinds. 29 CFR 1910.147
[See “Energy Isolating Device”]
[See “Tagout Device”]
lockout/tagout — The placement of a lock/tag on the energy isolating device in accordance with an established procedure, indicating that the energy isolating device shall not be operated until removal of the lock/tag in accordance with an established procedure. (The term “lockout/tagout” allows the use of a lockout device, a tagout device, or a combination of both.) ANSI Z244.1 – 2003, 2.10
machine or machinery — assembly, fitted with or intended to be fitted with a drive system consisting of linked parts or components, at least one of which moves, and which are joined together for a specific application. NOTE 1: The term “machinery” also covers an assembly of machines which, in order to achieve the same end, are arranged and controlled so that they function as an integral whole. ISO 12100:2010
Maintenance — combination of all technical and administrative actions intended to retain an item or a product in, or restore it to, a useful and safe condition in which it can perform the required function; this includes supervising actions, reconditioning, repairing, adjusting, and cleaning [IEV 191 – 07-01, modified] IEC 62079:2001, 3.9
Mechanically Linked – applies to mechanically linked auxiliary contact elements included in control circuit devices where actuating force is provided internally, such as contactor-relays. Linkage between the auxiliary and main contacts is not covered.
NOTE 1 A typical application of mechanically linked contact elements is e.g. self-monitoring in machine control circuits.
NOTE 2 Mechanically linked contact elements have previously been referred to as forced contacts, positively activated contacts, or linked contacts, or, in French: “contacts forcés” or in German: “Zwangsgeführte Kontakte”.
NOTE 3 Control circuit devices actuated externally (e.g. push-button or limit-switches) do not have an actuating force limited to a maximum value (see L.8.4 a) 2)), so they cannot have mechanically linked contact elements. For such devices, safety applications generally use contacts with “direct opening action” (see Annex K). IEC 60947 – 5‑1, Ed. 3, 2009 §L.1.1
Movable guarda guard generally connected by mechanical means (e.g., hinges or slides) to the machine frame or an adjacent fixed element and that can be opened without the use of tools. The opening and closing of this type of guard may be powered. CSA Z432-04, §3
Neutral Conductor – The conductor connected to the neutral point of a system that is intended to carry current under normal conditions. National Electrical Code. NFPA 70. National Fire Protection Association, Batterymarch Park. 2014.
Neutral Point – The common point on a wye-connection in a polyphase system or midpoint on a single-phase, 3‑wire system, or midpoint of a single-phase portion of a 3‑phase delta system, or a midpoint of a 3‑wire, direct-current system.
Informational Note: At the neutral point of the system, the vectorial sum of the nominal voltages from all other phases within the system that utilize the neutral, with respect to the neutral point, is zero potential.
- personal protective equipment
- special device or appliance designed to be worn or held by an individual for protection against one or more health and safety hazards IEC 82079 – 1, 2012, §3.27
- A short-duration, high-frequency sound, which has a slight echo. Ford Motor Company
- The physical quality of sound that relates to its frequency. Pitch increases as frequency increases and vice versa. Ford Motor Company
- Pinch Point
- Any point other than the trapping space at which it is possible for a part of the body to be caught between the moving parts of a machine or between moving and stationary parts of a machine or auxiliary equipment, resulting in injury. E2.19 Pinch Point. The term “pinch point,” as used in this standard, refers only to hazards that may exist as a part of the machine or its associated parts. The expression is not used to describe hazards caused by the tooling at the trapping space, since these hazards are a different problem and require different treatment. ANSI B11.8 – 1983 (R1999), §2.19
- [See ‘Ingoing Pinch Point’]
- positive drive
- a connection between actuator and contact element such that the force applied to the actuator is directly transmitted to the contact element IEC 60947 – 5‑1, Ed. 3, 2009 §22.214.171.124
- [Also see “Direct Drive”]
- Positively Guided
- Deprecated. See “Mechanically Linked”
- Point of Operation
- That point or area where the cutting edge(s) of the tool is in contact with the workpiece. ANSI B11.8 – 1983 (R1999), §2.20
- The precautionary principle (law & policy)
- The precautionary principle ensures that a substance or activity posing a threat to the environment is prevented from adversely affecting the environment, even if there is no conclusive scientific proof linking that particular substance or activity to environmental damage. The precautionary principle is a guiding principle. Its purpose is to encourage-perhaps even oblige-decision makers to consider the likely harmful effects of their activities on the environment before they pursue those activities. James Cameron and Juli Abouchar, The Precautionary Principle: A Fundamental Principle of Law and Policy for the Protection of the Global Environment, 14 B.C. Int’l & Comp. L. Rev. 1 (1991), http://lawdigitalcommons.bc.edu/iclr/vol14/iss1/2. Get this paper through Google Scholar.
- The precautionary principle or precautionary approach states that if an action or policy has a suspected risk of causing harm to the public or to the environment, in the absence of scientific consensus that the action or policy is harmful, the burden of proof that it is not harmful falls on those taking the action. Precautionary principle – Wikipedia
- In order to protect the environment, the precautionary approach shall be widely applied by States according to their capabilities. Where there are threats of serious or irreversible damage, lack of full scientific certainty shall not be used as a reason for postponing cost-effective measures to prevent environmental degradation. 1992 UNEP Rio Conference. “The Precautionary Principle”, United Nations Educational, Scientific and Cultural Organization, UNESCO, Paris, 2005.
Note – This version of the principle is sometimes referred to as the ‘weak precautionary principle’. Origin – German, 1930, Vorsorgeprinzip.Note – The precautionary principle is often cited in OHS work and could be paraphrased, “If a product, process or service is suspected of causing harm to people in the workplace, in the absence of scientific consensus that the product, process or service is harmful, lack of full scientific certainty shall not be used as a reason for postponing measures to reduce the risk of harm to people in the workplace. Those responsible for introducing the product, process or service into the workplace shall bear the burden of proof of safety relating to the safety of the product, process or service.”
Note: This is a version of the “strong precautionary principle.” – Doug Nix
- See The Precautionary Principle website.
- See the EU COMMUNICATION FROM THE COMMISSION on the precautionary principle
147 downloads 1.0 Doug Nix 2018-06-30 11:11
- See Late lessons from early warnings: the precautionary principle 1896 – 2000. Environmental issue report No 22.
136 downloads 1.0 Doug Nix 2018-06-30 11:30
- measure of the chance of occurrence expressed as a number between 0 and 1, where 0 is impossibility and 1 is absolute certainty
NOTE See definition 126.96.36.199, Note 2.
Risk management — Vocabulary. ISO Guide 73, §188.8.131.52. ISO International Organization for Standardization. 2009
- Protective measure
- means used to reduce risk NOTE Protective measures include risk reduction by inherently safe design, protective devices, personal protective equipment, information for use and installation, and training. ISO Guide 51:99
- See also “Complementary Protective Measures”
- protective conductor
- (identification: PE) conductor provided for purposes of safety, for example protection against electric shock
NOTE In an electrical installation, the PE conductor is normally also considered as a protective earthing conductor.[I EC 60050 – 195: 1998, 195 – 02-09], EN 60519 – 1:2011, 3.38
- protective earthing [protective grounding (US)]
- earthing a point or points in a system or in an installation or in equipment, for purposes of electrical safety
[IEC 60050 – 195:1998, 195 – 01-11], EN 60519 – 1:2011, 3.39
- protective equipotential bonding system (PEBS)
- equipotential bonding system providing protective-equipotential-bonding
[IEC 60050 – 826:2004, 826 – 13-31], EN 60519 – 1, 3.40
- protective earthing conductor [protective grounding conductor (US)]
- protective conductor provided for protective earthing
[IEC 60050 – 195:1998, 195 – 02-11], EN 60519 – 1:2011, 3.41
- proven in use
- demonstration, based on an analysis of operational experience for a specific configuration of an element, that the likelihood of dangerous systematic faults is low enough so that every safety function that uses the element achieves its required performance level (PLr)
[SOURCE: IEC 61508 – 4:2010, 3.8.18, modified.] ISO 13849 – 1:2015, 3.1.39
- Positive mode actuation
- If a moving mechanical component inevitably moves another component along with it, either by direct contact or via rigid elements, the second component is said to be actuated in the positive mode (or positively)by the first one. EN 1088:1996, §3.6
- Positive opening operation of a contact element
- The achievement of contact separation as the direct result of a specified movement of the switch actuator through non-resilient members (e.g. not dependent upon springs). (2.2 of chapter 3 ‘Special requirements for control switches with positive opening operation’ of EN 60947 – 5‑1: 1991). NOTE: For fluid power, the equivalent concept may be called ‘positive mode interruption’. EN 1088:1996, §3.7
- Pumping Feel
- A slow, pulsing movement. Ford Motor Company
rated voltage — voltage for which an installation (or a part thereof) is designed EN 60519 – 1:2011, 3.42
Rattle — A random and momentary or short-duration noise. Ford Motor Company
Reactor — The component, or part, that receives a vibration from an originator and conductor and reacts to the vibration by moving. Ford Motor Company
Reliability — ability of a machine or its components or equipment to perform a required function under specified conditions and for a given period of time without failing ISO 12100:2010 §3.2
Rustling — Intermittent sound of varying frequency, sounds similar to shuffling through leaves. Ford Motor Company
- use of a product, process or service in a way not intended by the supplier, but which may result from readily predictable human behaviour [3.14 of ISO/IEC Guide 51] IEC 62079:2001, 3.1
- use of a product in a way not described as intended use in the instructions for use, but which may result from readily predictable human behaviour
[SOURCE: ISO/IEC Guide 51 : 1999, definition 3.14, modified] IEC 82079 – 1, 2012, §3.31
- combination of the probability of occurrence of harm and the severity of that harm ISO Guide 51:99
- (of harm to an individual) a combination of the probability and the degree of the possible injury or damage to health in a hazardous situation. CSA Z432-04, §3
- A mechanical device that sometimes resembles a human and is capable of performing a variety of often complex human tasks on command or by being programmed in advance.
- A machine or device that operates automatically or by remote control.
- A person who works mechanically without original thought, especially one who responds automatically to the commands of others.
Read more: http://www.answers.com/topic/robot#ixzz1C697ZeGf [See Industrial Robot]
Roughness — A medium-frequency vibration. A slightly higher frequency than a shake. This type of vibration is usually related to drivetrain components. Ford Motor Company
- freedom from unacceptable risk
NOTE Adapted from ISO/IEC Guide 2:1996, definition 2.5. ISO Guide 51:99
- freedom from unacceptable risk of harm
NOTE In standardization, the safety of products, processes and services is generally considered with a view to achieving the optimum balance of a number of factors, including non-technical factors such as human behaviour, that will eliminate avoidable risks of harm to persons and goods to an acceptable degree. ISO Guide 2:2004, §2.5
- freedom from unacceptable risk
- safety – related part of a control system (SRP/CS)
- part of a control system that responds to safety-related input signals and generates safety-related output signals.
- NOTE 1 The combined safety-related parts of a control system start at the point where the safety-related input signals are initiated (including e.g. the actuating cam and the roller of the position switch) and end at the output of the power control elements (including, for example, the main contacts of a contactor). NOTE 2 If monitoring systems are used for diagnostics, they are also considered as SRP/CS. ISO 13849 – 1:2006, 3.1.1
- screening test
- test carried out to detect and remove non-conforming items, or those susceptible to early life failure
- Note 1 to entry: The test may employ representative or elevated stresses. IEC 60065, 192 – 09-11
- set of functions offered to users by supplier’s organization supporting clients with maintenance IEC 60050, 191 – 01-04, modified IEC 62079:2001, 3.16
- See Wiktionary.
- A low-frequency vibration, usually with visible component movement. Usually relates to tires, wheels, brake drums or brake discs if it is vehicle speed sensitive, or engine if it is engine speed sensitive. Also referred to as a shimmy or wobble. Ford Motor Company
- An abnormal vibration or wobbling, felt as a side-to-side motion of the steering wheel in the driveshaft rotation. Also described as waddle. Ford Motor Company
- A low-frequency vibration that is felt through the steering wheel or seat during light brake application. Ford Motor Company
- single fault condition<.dt>
- condition in which one means for protection against hazard is defective
- NOTE If a single fault condition results unavoidably in another single fault condition, the two failures are considered as one single fault condition.IEC 60050 – 851:2008, 851 – 11-20, EN 60519 – 1:2011, 3.45
- Skilled person
- person with relevant education and experience to enable him or her to perceive risks and to avoid hazards which operation or maintenance of a product can create [IEV 195 – 04-01 and 3.52 of IEC 60204 – 1, modified] IEC 62079:2001, 3.17
- individual with relevant technical education, training and/or experience enabling him or her to perceive risks and to avoid hazards occurring during use of a product [SOURCE: IEV 195 – 04-01 , modified and IEC 60204 – 1 :2005, definition 3.53, modified] IEC82079‑1, 2012, §3.37
- (electrically) skilled person — person with relevant education and experience to enable him or her to perceive risks and to avoid hazards which electroheating installations can create
[IEC 60050 – 826:2004, 826 – 18-01, modified], EN 60519 – 1:2011, 3.8
- A resonance from flat surfaces, such as safety belt webbing or door trim panels. Ford Motor Company
- document, established by consensus and approved by a recognized body, that provides, for common and repeated use, rules, guidelines or characteristics for activities or their results, aimed at the achievement of the optimum degree of order in a given context
- Note 1 to entry: Standards should be based on the consolidated results of science, technology and experience, and aimed at the promotion of optimum community benefits [SOURCE: ISO/IEC Guide 2:2004, clause 3.2]
- activity of establishing, with regard to actual or potential problems, provisions for common and repeated use, aimed at the achievement of the optimum degree of order in a given context
- Note 1 in entry: In particular, the activity consists of the processes of formulating, issuing and implementing standards.
- Note 2 in entry: Important benefits of standardization are improvement of the suitability of products, processes and services for their intended purposes, prevention of barriers to trade and facilitation of technological coöperation. ISO Guide 59:2018, 3.9
- standstill frequency
- A programmed fixed reference value for recognition of standstill. On frequency “standstill,” the enable circuits are switched on and guard locking solenoids controlled by a fail-safe standstill monitor are released. Schmersal Canada Ltd.
- standstill monitor
- On standstill of a machine, the monitor gives the enable signal that can be used to release guard locking devices or create a safe access condition. See “fail-safe standstill monitor.” Adapted from Schmersal Canada Ltd.
- state of the art
- developed stage of technical capability at a given time as regards products, processes and services, based on the relevant consolidated findings of science, technology and experience ISO Guide 2:2004, §1.4 See “Acknowledged Rule of Technology”
- Any norm, convention or requirement Technical Standard, [online]. Wikipedia. Available: http://en.wikipedia.org/wiki/Technical_standard. Accessed: 13-Jun-13.
- ISO Standards Taxonomy (Standard Types)
- type‑A standard — Basic safety standard. Standard giving basic concepts, principles for design and general aspects that can be applied to machinery. Note 1 to entry: See ISO 12100:2010, Introduction.ISO Guide 78, 3.1. ISO International Organization for Standardization, Geneva. 2012.
- type‑B standard — Generic safety standard. Standard dealing with one safety aspect or one type of safeguard that can be used across a wide range of machinery. Note 1 to entry: See ISO 12100:2010, Introduction.ISO Guide 78, 3.2. ISO International Organization for Standardization, Geneva. 2012.
- type-B1 standard — Type‑B standard on particular safety aspects (for example, safety distances, surface temperature, noise). Note 1 to entry: See ISO 12100:2010, Introduction.ISO Guide 78, 3.2.1. ISO International Organization for Standardization, Geneva. 2012.
- type-B2 standard — Type‑B standard on safeguards (for example, two-hand control devices, interlocking devices, pressure sensitive devices, guards). Note 1 to entry: See ISO 12100:2010, Introduction.ISO Guide 78, 3.2.2. ISO International Organization for Standardization, Geneva. 2012.
- type‑C standard — Machine safety standard. Standard dealing with detailed safety requirements for a particular machine or group of machines. Note 1 to entry: See ISO 12100:2010, Introduction.Note 2 to entry: The term “group of machines” means machines having a similar intended use and similar hazards, hazardous situations or hazardous events.ISO Guide 78, 3.3. ISO International Organization for Standardization, Geneva. 2012.
- Stopping time (time for hazard elimination)
- The period between the point at which the interlocking device initiates the stop command and the point at which the risk from hazardous machine functions has passed EN 1088 – 1996, §3.8
- A high-pitched transient sound, similar to rubbing fingers against a clean window. Ford Motor Company
- A long-duration, high-pitched noise. Ford Motor Company
Tap — A light, rhythmic or intermittent hammering sound, similar to tapping a pencil on a table edge. Ford Motor Company
tagout — The placement of a tagout device on an energy isolating device, in accordance with an established procedure, to indicate that the energy isolating device and the equipment being controlled may not be operated until the tagout device is removed. 29 CFR 1910.147
- A prominent warning means such as a tag and a means of attachment, which can be securely fastened to an energy isolating device to indicate that the energy isolating device and the equipment being controlled may not be operated until the tagout device is removed. ANSI Z244.1 – 2003, 2.20.1
- A prominent warning device, such as a tag and a means of attachment, which can be securely fastened to an energy isolating device in accordance with an established procedure, to indicate that the energy isolating device and the equipment being controlled may not be operated until the tagout device is removed. 29 CFR 1910.147
Thump — A dull beat caused by 2 items striking together. Ford Motor Company
Tick — A rhythmic tap, similar to a clock noise. Ford Motor Company
Tip-In Moan — A light moaning noise heard during light vehicle acceleration, usually between 40 – 100 km/h (25 – 65 mph). Ford Motor Company
MS101 Note: In our opinion, tolerable risk bears a requirement for continuous monitoring and improvement that is completely missed in this definition. Here is an alternate definition for tolerable risk that better encompasses this requirement: tolerable risk — risk that may be endured in a given context based on current information and values of society, subject to continuous monitoring and reduction.
Transient — A noise or vibration that is momentary, a short duration. Ford Motor Company
Trapping Space — The space where it would be possible for any part of an individual’s body to be trapped between the cutter or its mounting and the workpiece or fixture, resulting in injury. ANSI B11.8 – 1983 (R1999), §2.26
NOTE 1: This can be caused by, for example:
- a start command which is the result of a failure in, or an external influence on, the control system;
- a start command generated by inopportune action on a start control or other parts of the machine such as 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.
NOTE 2: Machine start-up during normal sequence of an automatic cycle is not unintended, but can be considered as being unexpected from the point of view of the operator, Prevention of accidents in this case involves the use of safeguarding measures (see 6.3). NOTE 3 Adapted from ISO 14118:2000, definition 3.2. ISO 12100:2010
- Any motion, shaking or trembling, that can be felt or seen when an object moves back and forth or up and down. Ford Motor Company
- The act of vibrating, or the state of being vibrated, or in vibratory motion; quick motion to and fro; oscillation, as of a pendulum or musical string. 1913 Webster’s Dictionary
- (Physics) A limited reciprocating motion of a particle of an elastic body or medium in alternately opposite directions from its position of equilibrium, when that equilibrium has been disturbed, as when a stretched cord or other body produces musical notes, or particles of air transmit sounds to the ear. The path of the particle may be in a straight line, in a circular arc, or in any curve whatever.Note: Vibration and oscillation are both used, in mechanics, of the swinging, or rising and falling, motion of a suspended or balanced body; the latter term more appropriately, as signifying such motion produced by gravity, and of any degree of slowness, while the former applies especially to the quick, short motion to and fro which results from elasticity, or the action of molecular forces among the particles of a body when disturbed from their position of rest, as in a spring. 1913 Webster’s Dictionary
- (n) The act of vibrating Wordnet 3.0
- (physics) a regular periodic variation in value about a mean. Wordnet 3.0
- well-tried component
- A “well-tried component” for a safety-related application is a component which has been either
a) widely used in the past with successful results in similar applications, or
b) made and verified using principles which demonstrate its suitability and reliability for safety-related applications.
Newly developed components and safety principles may be considered as equivalent to “well-tried” if they fulfil the conditions of b).
The decision to accept a particular component as being “well-tried” depends on the application.
NOTE 1 Complex electronic components (e.g. PLC, microprocessor, application-specific integrated circuit) cannot be considered as equivalent to “well tried”.
- ISO 13849 – 1, 6.2.4
- A constant, high-pitched noise. Also described as a screech. Ford Motor Company
- High-pitched noise with a very narrow frequency band. Examples of whistle noises are a turbocharger or air flow around an antenna. Ford Motor Company
- Wind Noise
- Any noise caused by air movement in, out or around the vehicle. Ford Motor Company