Chapter 2
Important Terms
These terms are very important
for us to understand the
content !
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2.1 Intended Use/Purpose
Use of a Product, Process or Service in
accordance with the specifications,
instructions and information provided by
the manufacturer.
ANSI/AAMI/ISO 14971:2000, definition 2.5
预期用途/目的
按照制造商提供的规范、说明书和信息，对产品、过程或服务的使用。
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2.2 Harm
Physical injury or damage to health of people,
or damage to property or the environment.
ISO/IEC Guide 51:1999, definition 3.3“Guidelines for
inclusion of safety aspects in standards.”
损害
对人体健康的实际伤害或侵害，或是对财产或环境的侵害。
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2.3 Hazard
Potential source of Harm.
危害
损害的潜在源。
• Human injury or death
• Damage to the
environment
• Damage to physical assets
• Loss of production
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2.4 accident
An unintentional event that causes harm to
people, property or environment.
major accident: an incident involving multiple
injuries, a fatality. And extensive property
damage.
occupational accident : an accident, the origins
of which are from a workplace.
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2.5 Risk
Combination of the probability of occurrence
of harm and the severity of harm.
Risk is the combination of the probability, or frequency of
occurrence of a defined hazard and the magnitude of
consequences of the occurrence. It is therefore a measure
of the likelihood of a specific undesired event and its
unwanted consequences or loss.
风险
损害的发生概率与损害严重程度的结合。
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2.5 risk
The expectation of loss.
An expression of the combined severity and
probability of loss.
The long-term rate of loss; the loss rate value.
Risk (
Expected Loss
Unit Time or Activity)
= Severity (
Loss
Loss Event)
x Probability (
Loss Events
Unit Time or Activity)
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Further definitions - risk
Tolerable Risk A risk that is allowed to exist,
so that certain benefits can be gained - there
being a level of confidence that the risk is under
control.
Intolerable Risk A risk that cannot be justified
except in extraordinary circumstances.
Negligible Risk A risk that is so small and
insignificant that it can be ignored as long as
existing precautions remain in place.
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2.6 Residual Risk
Risk remaining after protective measures have
been taken.
ISO/IEC Guide 51:1999, definition 3.9
剩余风险
采取防护措施后余下的风险。
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hazard
10
Accidental event
11
accident
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2.7 Risk analysis
Systematical use of available information to
identify hazards and to estimate the risk.
ISO/IEC Guide 51:1999, definition 3.10
风险分析
系统运用可得资料，判定危害并估计风险。
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2.8 Risk evaluation
Judgment, on the basis of risk analysis, of
whether a risk which is acceptable has been
achieved in a given context based on the
current values of society.
ISO/DIS 14971:1999-07
风险评价
在风险分析的基础上，根据给定的现行社会价值观，对风险是否达到可接
受水平的判断。
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2.9 Risk assessment
Overall process of risk analysis and risk evaluation.
ISO/IEC Guide 51:1999, definition 3.12
风险评定
包括风险分析和风险评价的全部过程。
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2.10 Risk control
The process through which decisions are reached
and implemented for reducing risks to or
maintaining risks within specified levels.
ISO/DIS 14971:1999-07
风险控制
作出决策并实施保护措施，以便降低风险或把风险维持在规定水平的过程。
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2.11 Risk management
Systematic application of management policies,
procedures and practices to the tasks of analyzing,
evaluating and controlling risk.
ISO/IEC Guide 51:1999
风险管理
用于风险分析、评价和控制工作的管理方针、程序及其实践的系统运用。
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Risk management option
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2.12 mishap
An event in which loss is experienced.
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2.13 miss
An event having potential potential for loss,
but resulting in little or no loss.
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2.14 safety (security)
1) Freedom from accidents (loss events)
Freedom from those conditions that can cause
death, injury, occupational illness or damage
to or loss of equipment or property, or damage
to environment.
2) The quality of a system that allows the
system to function under a predetermined
condition with an acceptable minimum of
accidental loss
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2.15 safety management
A systematic control of worker performance, machine
performance, and physical environment. The control
includes both prevention and correction of unsafe
conditions and circumstances.
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2.16 safety policy
A management definition of the safety and health
related actions to be followed in the work organization.
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2.17 safety review
An inspection of a plant or process unit, drawings,
procedures, emergency plans, and/or management
systems, etc. often by a team, and usually problemsolving in nature.
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2.18 system safety engineering
The system engineering processes used to prevent
accidents by identifying and eliminating or controlling
hazards. Note that hazards are not the same as failures;
dealing with failures is usually the province of reliability
engineering.
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2.19 incident
An unplanned event that has the potential to lead to an
accident.
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2.20 Probability
The chance or the likelihood of occurrence of an event.
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2.21 Reliability
The probability that an item will perform its intended
function for a specified mission profile.
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2.22 Consequence Categories
Consequence types
Level
Description
People
1
CATASTROPHI
C
Environment
Property
Several fatalities
Time for restitution of
ecological resources ＞5years
Total loss of system and
major damage outside
system area
Loss of main part of
system. Production
interrupted for months
2
SEVERE LOSS
One fatalities
Time for restitution of
ecological resources ＞25years
3
MAJOR
DAMAGE
Permanent disability,
prolonged hospital
treatment
Time for restitution of
ecological resources ＜2years
Considerable system
damage. Production
interrupted for weeks.
4
DAMAGE
Medical treatment.
loss time injury
Local environment damage of
short duration(＜1month)
Minor system damage
Minor production
influence
5
MINOR
DAMAGE
Minor injury
Annoyance.
Disturbance
Minor environmental damage
Minor property damage
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