1 Scope
This standard defines basic terminology and methodology used in achieving safety of machinery.
The provisions stated in this standard are intended for the designer.
This standard does not deal with damage to domestic animals, property or the environment.
2 Normative References
The following standards contain provisions which, through reference in this Part of 15706, constitute provisions of this part. For dated references, all subsequent modification or revision (excluding correction contents) are not applicable to this Part. However, all concerned Parties are encouraged to study if the latest editions of these documents can be applied. For undated references, the latest editions of the normative documents are applicable to this Part.
GB/T 15706.2-2007, Safety of machinery - Basic concepts, general principles for design - part 2: Technical principles.
3 Terms and Definitions
For the purposes of this standard, the following terms and definitions apply.
3.1
Machinery
Machine
Assembly of linked parts or components, at least one of which moves, with the appropriate machine actuators, control and power circuits, joined together for a specific application, in particular for the processing, treatment, moving or packaging of a material.
The terms "machinery" and "machine" also cover an assembly of machines which, in order to achieve the same end, are arranged and controlled so that they function as an integral whole.
Note: Annex A provides a general schematic representation of a machine.
3.2
Reliability (of a machine)
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
3.3
Maintainability (of a machine)
Ability of a machine to be maintained in a state which enables it to fulfill its function under conditions of intended use, or restored into such a state, the necessary actions (maintenance) being carried out according to specified practices and using specified means
3.4
Usability (of a machine)
Ability of a machine to be easily used thanks to, among others, properties or characteristics that enable its function(s) to be easily understood
3.5
Harm
Physical injury or damage to health
3.6
Hazard
Potential source of harm
Note 1: the term "hazard" can be qualified in order to define its origin (e.g. mechanical hazard, electrical hazard) or the nature of the potential harm (e.g. electric shock hazard, cutting hazard, toxic hazard, fire hazard).
Note 2: the hazard envisaged in this definition:
—Either is permanently present during the intended use of the machine (e.g. motion of hazardous moving elements, electric arc during a welding phase, unhealthy posture, noise emission, high temperature);
—Or may appear unexpectedly (e.g. explosion, crushing hazard as a consequence of an unintended / unexpected start¬up, ejection as a consequence of a breakage, fall as a consequence of acceleration / deceleration).
3.7
Relevant hazard
Hazard which is identified as being present at or associated with the machine
Note: a relevant hazard is identified as the result of one step of the process described in GB/T 16856.
3.8
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
3.9
Hazardous situation
Circumstance in which a person is exposed to at least one hazard. The exposure can immediately or over a period of time result in harm
3.10
Hazard zone/danger zone
Any space within and/or around machinery in which a person can be exposed to a hazard
3.11
Risk
Combination of the probability of occurrence of harm and the severity of that harm
3.12
Residual risk
Risk remaining after protective measures have been taken (see also figure 1)
Note: this standard distinguishes:
The residual risk after protective measures have been taken by the designer;
The residual risk after all protective measures have been implemented.
3.13
Risk assessment
Overall process comprising a risk analysis and a risk evaluation
3.14
Risk analysis
Combination of the specification of the limits of the machine, hazard identification and risk estimation
3.15
Risk estimation
Defining likely severity of harm and probability of its occurrence
3.16
Risk evaluation
Judgment, on the basis of risk analysis, of whether the risk reduction objectives have been achieved
3.17
Adequate risk reduction
Risk reduction at least in accordance with the legal requirements under consideration of the current state of the art
Note: criteria for determining when adequate risk reduction is achieved are given in 5.5.
3.18
Protective measure
Measure intended to achieve risk reduction, implemented:
By the designer (inherently safe design, safeguarding and complementary protective measures, information for use) and
By the user (organization: safe working procedures, supervision, permit-to-work systems; provision and use of additional safeguards; use of personal protective equipment; training).
See figure 1.
3.19
Inherently safe design measure
Protective measure which either eliminates hazards or reduces the risks associated with hazards by changing the design or operating characteristics of the machine without the use of guards or protective devices
Note: GB/T 15706.2—2007, clause 4, deals with risk reduction by inherently safe design measures.
3.20
Safeguarding
Protective measure using safeguards to protect persons from the hazards which cannot reasonably be eliminated or from the risks which cannot be sufficiently reduced by inherently safe design measures
Note: GB/T 15706.2—2007, clause 5, deals with safeguarding.
3.21
Information for use
Protective measure consisting of communication links (e.g. texts, words, signs, signals, symbols, diagrams) used separately or in combination, to convey information to the user
Note: GB/T 15706.2—2007, clause 6, deals with information for use.
3.22
Intended use of a machine
Use of a machine in accordance with the information provided in the instructions for use
3.23
Reasonably foreseeable misuse
Use of a machine in a way not intended by the designer, but which may result from readily predictable human behaviour
3.24
Safeguard
Guard or protective device
3.25
Guard
Physical barrier, designed as part of the machine, to provide protection
Note 1: a guard may act:
—Alone; it is then only effective when it is "closed" for a movable guard or "securely held in place" for a fixed guard;
—In conjunction with an interlocking device with or without guard locking; in this case, protection is ensured whatever the position of the guard.
Note 2: depending on its design, a guard may be called e.g. Casing, shield, cover, screen, door, enclosing guard.
Note 3: see GB/T 15706.2—2007 5.3.2, and GB/T 8196 for types of guards and their requirements.
3.25.1
Fixed guard
Guard affixed in such a manner (e.g. by screws, nuts, welding) that it can only be opened or removed by the use of tools or destruction of the affixing means
3.25.2
Movable guard
Guard which can be opened without the use of tools
3.25.3
Adjustable guard
Fixed or movable guard which is adjustable as a whole or which incorporates adjustable part(s). The adjustment remains fixed during a particular operation
3.25.4
Interlocking guard
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
Note: GB/T 18831 gives detailed provisions.
Foreword I
1 Scope
2 Normative References
3 Terms and Definitions
4 Hazards to be Taken into Account When Designing Machinery
5 Strategy for Risk Reduction
Annex A (Informative) Schematic Representation of a Machine
Bilingual Index of Specific Terms and Expressions Used in GB/T
Bibliography
