1 Chapter 2 Important Terms These terms are very important for us to understand the content !

2 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。

3 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。

4 2.3 Hazard Potential source of Harm. Human injury or death Damage to the environment Damage to physical assets Loss of production 危害 损害的潜在源。

5 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.

6 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。

7 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 ( ) = Severity ( ) x Probability ( ) Expected Loss Unit Time or Activity Loss Loss Event Loss Events Unit Time or Activity

8 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. Further definitions - risk

9 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。

10 hazard

11 Accidental event

12 accident

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。

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: 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。

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。

Risk control The process through which decisions are reached and implemented for reducing risks to or maintaining risks within specified levels. ISO/DIS 14971: 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。

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。

18 Risk management option

19 An event in which loss is experienced mishap

miss An event having potential potential for loss, but resulting in little or no loss.

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

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.

safety policy A management definition of the safety and health related actions to be followed in the work organization.

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 problem- solving in nature.

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.

incident An unplanned event that has the potential to lead to an accident.

Probability The chance or the likelihood of occurrence of an event.

Reliability The probability that an item will perform its intended function for a specified mission profile.

Consequence Categories LevelDescription Consequence types PeopleEnvironmentProperty 1 CATASTROPHI C Several fatalities Time for restitution of ecological resources ＞ 5years Total loss of system and major damage outside system area 2SEVERE LOSSOne fatalities Time for restitution of ecological resources ＞ 2- 5years Loss of main part of system. Production interrupted for months 3 MAJOR DAMAGE Permanent disability, prolonged hospital treatment Time for restitution of ecological resources ＜ 2years Considerable system damage. Production interrupted for weeks. 4DAMAGE 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 damageMinor property damage