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Risk Management Principles

37 important questions on Risk Management Principles

What is risk assesment?

- Systematic approach to organizing and analysing scientific knowledge for potential hazards that might pose risk under specific circumstances
- Included in risk management

What are the hazard levels in risk management?

- Environment
- Technical/economic
- Social/people

The accident pyramid (Bird)

There is a proven ratio relationship between incidents with no visible injury or damage and those who do not. So it's possible to prevent serious accidents by taking measures aimed at near misses and minor accidents. This provides insight in Type I accidents where there is a lot of data.

Assumptions of the Bird accident pyramid

I. As injuries increase in severity, their number decreases in frequency
II. All injuries of lower severity have the same potential for injury
III. Injuries of differing severity have the same underlying causes
IV. Reduction strategy will impact equally (reducing minor injuries by 20% will also reduce major injuries by 20%)

Assumptions of the improved accident pyramid

I All minor injuries are not the same in their injury potential
II Injuries of differing severity have differing underlying causes
III Reducing injury requires different strategies per type of injury
IV Reduction strategy should use precursor data

The improved accident pyramid

- Makes a distinction between different types of risk
- Regular accidents should not be confused with serious accidents
- Not all near misses become serious accidents
- Old accident pyramids leads to disaster blindness
- Both types of risk should receive measures

The P2T model (Reniers and Dullaert)

- If accidents result from holes in the security system, those need to be plugged
- Three dimensions in which measures can be taken to avoid and prevent unwanted events and mitigate their consequences
- 3 dimensions: people, procedures and technology

People: Indicates how people (indivually/group) think about and deal with risks in an organization
Procedures: Concerns management measures that are taken to tackle risks
Technology: Technological measures taken and implemented

Swiss Cheese Model (Reason)

- Explains the existence of accidents by holes in the risk management system
- Solid insight into the organization allows for detection of holes
- Risk assesment can identify suitable measures for closing holes
- Model is dynamic
- Adequate risk management should make the holes as small as possible

What is an independent protection layer (IPL)?

- Because inherent safety is hard to reach within economic constraints potential hazards remain
- To reduce operating risks to an acceptable level independent protection layers are specified
- IPL can be described as a device, system or action that is capable of preventing a scenario from proceeding to its undesired consequence independent of the initiating event or the action of any other layer of protection associated with the scenario.

What are the characteristics of an IPL (Powell)?

- Specific. Designed to prevent or mitigate specific, potentially hazardous events
- Independent. Independent of other protective layers associated with the identified hazard
- Dependable. Operates in a prescribed manner, with acceptable reliability.
- Auditable. Designed to facilitate regular validation and maintenance (including testing) of protective functions
- Reducing. Likelihood of identified hazardous event must be reduced by a factor of at least 100

Summary of IPL, SIF and SIL

- Determining necessity for IPLs and SIfs and level of safety integrity is done using risk identification and evaluation.
- In highly technical environments SIL is chosen to reduce incident frequency to a tolerable level
- SIL is the design basis for all engineering decisions related to the SIF
- Completed design must be validated against the SIL
- Design cycle: hazards identification -> requirements quantification -> design validation

What is ALARP/ALARA?

ALARP: As low as reasonably practicable/possible
ALARA: As low as reasobably achievable

- Reasonably practicable means weighing risks against trouble, time and money needed to control. This determines a level to which we expect risk to be controlled.
- It is common where an industrial risk is calculated to generate risks in the intermediate zone and recquire them to be reduced to an ALARP level (if benefits of risk activity outweigh generated risks

What is an individual risk?

- Frequency with which a person may expect to sustain a specified level of harm as a result of an adverse event involving a specific hazard
- This can be more general (individual in genpop) or specific (individual in specified section of community)

What is a location based risk?

- A location based risk is the geographic distribution of individual risk for an organization
- Location based risk is used to assess whether individuals are exposed to more than an acceptable risk in the locations they spend time.

What is a societal risk?

- Probability that a group of a certain size will be harmed - usually killed - simultaneously by the same event or accident.
- Often presented in the form of an FN curve (Frequency - Number of fatalities)
- Societal risk is designed to display how risks vary with changing levels of severity (1 fatality = acceptable, but is 100?)
- Severity of an event increases, people become more risk averse

Physical characterization of risk

1. A hazard
2. One or more targets threatened by the hazard
3. Evaluation of the threat
4. Measures taken to reduce it

Four elements show that a protection/prevention barrier is recquired to prevent threat reaching target.

What is the difference between an incident and an accident?

The importance of caused or sustained damage

Incident: event that leads or could have led to an accident
Accident: unexpected event that leads to health deterioration, lesions, damages or other losses.

Consequence spectrum Incident -> Accident -> Disaster

What are two possibilities to describe physical risk?

1. Static modelling
2. Dynamic modelling

What is a static model of an accident?

If risk = potential, accident = reality. It is realized as soon as a threat reaches the target. Prevention or protection barrier has partially done its job. Failure is represented by holes. There is no time scale included

What is a dynamic model of an accident?

Often its sequences of other events, the succession of an incident which leads to damage. These succesive incidents can induce more hazardous situations. Likelihood of an occurence increases to a critical level

What are the four zones of the dynamic model?

1. At time zero, protective/preventive barrier fulfills its purpose, no threats reach target.
2. Small incidents happen, time decreases protection/prevention/efficiency. First observable precursors.
3. Time continues, degradation of barrier is sufficient for hazard to reach target. ACCIDENT!
4. The consequences of the accident are losses and damages

Three levels of organizational culture?

1. Artifacts (visible structures and processes, observable behavior)
2. Espoused beliefs and values (ideals, ideologies, rationalizations)
3. Basic underlaying assumptions (unconscious, taken for granted)

What are safety culture and climate models?

- P2T
- Egg aggregated and TEAM model
- Security culture model
- PDCA
- S & S

What are types of human error?

- Failures of expertise. Slecht geïmplementeerd plan
- Failures from lack of expertise: Slecht plan door gebrek aan expertise
Of:
- Skill-based behavior errors
- Rule-based behavior errors
- Knowledge-based behavior errors

What is an organizational climate?

- The product of some of the underlying assumptions, the way in which a company’s culture is visible for the outside world’.
- Safety climate is a snapshot of safety culture
- Climate displays what the perception of the culture is to the members of that culture

P2T model for safety and security culture

- A model to integrate all observable safety and security culture aspects.
- Dimensions are people, procedures and technology
- People: safety and security management training, awareness, competence profiles
- Procedures: Safety or security management system (which revise existing procedures), working procedures
- Technology: Prevention and mitigation technology, risk software and tools

TEAM model of safety culture

- The egg is composed of three layers of safety culture
- The yolk represents observable factors (ENGINEERING)
- The protein represents psychological and perceptual factors (PERCEPTUAL)
- The air in the egg represents beliefs, affective and cognitive processes and self control (PSYCHOLOGICAL)

Measurable indicators for TEAM model

1. Document analyses and quantitative analysis for the engineering field of observable factors
2. Quantitative analyses (questionnaires) for determining safety climate
3. Qualitative analyses to find out individual and human related states in regards to safety.

TEAM model of security culture

- Three domains make constituting parts
- Observational domain with respect to security
- A perceptual domain (security climate)
- Motivational (intended behavior domain).

Indicators for safety culture

● Commitment at all levels

● Safety and health are treated as an investment not a cost
● Safety and health is part of continuous improvement
● Training and information is provided for everyone
● A system for workplace analysis and hazard prevention and control is in place
● The environment in which people work is blame free
● The organisation celebrates successes

What are the five phases of strategic management?

1. Strategic vision of the organization. This makes clear what the organization should look like and how it should evolve
2. Translate the strategic vision into clearly measurable objectives
3. Organization develops a strategy to reach its goals. This needs to include specific domains
4. Strategy should be implemented, efficiently and effectively
5. Performance valuation and implementation of changes

Difference between safety culture and safety climate?

Safety culture = an enduring characteristic of an organization that is reflected in its consistent way of dealing with safety issues.

Safety climate = temporary state of an organization that is subject to change depending on the features of the specific operational or economic circumstances. Also, a psychological phenomenon.

What are normal accident theory and hight reliability theory?

NAT = major accidents are inevitable (companies don’t use models right)

HRT = all accidents are inevitable (by organizational design and management techniques)

Ideally, systems should be made as linear as possible, since effects become more predictable

High reliability organizations

Collective mindfulness through situational awareness and questioning attitude

Five key principles: 1 to 3 consider anticipation 4 to 5 consider reaction

1. Proactively and actively looking at failures and deviations
2. Reluctant for simplification of data
3. Continuous attention towards real-time information (learn from nearmisses)
4. Devoted to resiliency (to cope and bounce back from accidents)
5. Respectful for expertise (at incident hierarchy is goes to most experienced worker)

What is reliability engineering?

The degree of safety depends on the maintenance procedures and on actions intended to keep the organization safe.

RAM = reliability, availability and maintainability

What are the main features of a black swan event?

§ After the occurrence of the event, explanations are formulated making it predictable or expectable
§ The event has extreme or major impact
§ The event is unexpected or not probable

What are the risk management models?

1. Accident pyramid (Bird)
2. Improved accident pyramid (Reniers, Hopkins)
3. P2T (Reniers)
4. Swiss Cheese Model (Reason)
5. Improved Swiss cheese model (Reniers)
6. Domino model for accidents (Heinrich)

The question on the page originate from the summary of the following study material:

Engineering Risk Management in Organizations

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