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Salvatore Bagnato

Operations Manager – Ed.Ina Donje Svetice

In both the daily aspects of social life and in the management of issues relating to the life of companies, there is often confusion between the terms risk and hazard.

The meaning of the word hazard can be confusing. Often dictionaries do not give specific definitions or combine it with the term risk, which helps explain why many people use the terms interchangeably and, therefore, often incorrectly.

There are many definitions of danger and risk. Still, among them, we will propose the one relating to the new ISO 45000, since management systems today represent an essential aspect of the organization of any company that wishes to achieve its business objectives. Today, it is impossible to separate the economic issues from those concerning the health and safety of workers as well as respect for and protection of the environment.

ISO 45001 defines a hazard as a “source or situation with a potential to cause injury and ill health,” while the risk is defined as the “combination of the likelihood of occurrence of a work‐related hazardous event or exposure(s) and the severity of injury and ill health that can be caused by the event or exposures.”

So, the hazard is the feature of the process that can harm an individual, and the risk is the likelihood that it will happen, along with how severe the consequences will be.

The risk assessment process is also, in this case, an intrinsic component of each person’s life and allows, consciously or unconsciously, to manage risks of any nature (related to health, economics, etc.) by operating with preventive actions (to reduce the probability that an event is assessed to happen) or mitigative (to minimize the effects that this event can cause).

The process of risk assessment is somewhat informal at the individual social level but can become a sophisticated process at the strategic corporate level. However, in both cases, the ability to anticipate future events and create effective strategies for mitigating them when deemed unacceptable is vital.

Risk assessment is the process that:

 Identifies hazards and risk factors that have the potential to cause harm (hazard identification).

 Analyzes and evaluates the risk associated with that hazard (risk analysis and risk evaluation).

 Determines appropriate ways to eliminate the hazard or control the risk when the hazard cannot be removed (risk control).

In many companies now, the risk is fully integrated into the strategic planning process and in the context of the organization’s performance. Risk management is permeated within the company, determining those changes that can transform the negative potential that could lead to crises or failures into growth opportunities.

In the scientific literature and the various standards of management systems, today, there are different definitions that all have in common the presence of three elements:

1 Hazards

2 Consequence seriousness

3 Frequency of a specific scenario

There is a risk if a given event is considered (with its probability of occurrence) and, depending on the type of impact, an opportunity, a loss, or the presence of uncertainty is determined. Events that have only negative consequences are indicated as pure risks. In general, a tolerability threshold is set for them and managed in such a way as to fall within this threshold.

Generally, there are three types of risk assessment, namely qualitative (Q), semi‐quantitative (SQ), and quantitative risk assessment (QRA).

In QRA, numerical values are independently assigned to the various risk assessment components and the level of potential losses. When all the elements (threat frequency, safeguard effectiveness, safeguard costs, uncertainty, and probability, etc.) are quantified, the process is considered entirely quantitative.

In the SQ, frequency and severity are approximately quantified within ranges.

Finally, Q does not assign numerical values to the risk assessment components. It is based on the scenario. Several threat vulnerability scenarios are determined by trying to answer “what‐if” questions. In general, qualitative risk assessment tends to be more subjective in nature

The lower levels of assessment (Q and SQ) are considered most appropriate for screening for hazards and events that need to be analyzed in greater detail. One approach to deciding the proper level of detail could be to start with a qualitative approach and to add for more detail whenever it becomes apparent that the current level is unable to offer an understanding of the risks, discrimination between the risks of different events, and so on.

It is possible to refer to the existing literature (widely used by many states in the promulgation of laws and regulatory provisions) to analyze the numerous methodologies implemented over time, in particular, to support sectors of activity characterized by elements of risk that could determine if the event were to occur, and serious consequences for people and the environment, as well as for the company itself (O&G, nuclear, etc,).

The first step for the risk assessment is hazard identification. Hazard identification (HAZID), hazard and operability (HAZOP), safety integrity level (SIL), failure modes and effects analysis (FMEA), what‐if (WI), and safety checklist (SCL) are all examples of methodologies used worldwide.

The next steps are:

 Risk estimation and ranking of risk

 Risk evaluation

 Implementation of risk reduction

The output of the risk estimation should be a list of risks in ranked order for consideration. The process of risk evaluation starts with the highest risk. It proceeds down the list of identified potential risk reduction measures until it is evident that no further risk reduction measures can be justified. It should be demonstrated that risks are controlled to ensure compliance with the relevant provisions, and not intolerable. Risk estimation needs assessing both the severity (consequence) and frequency (likelihood) of hazardous events. For the Q or SQ approaches, a risk matrix is a convenient method of ranking and presenting the results.

A risk reduction measures study should be carried out by a multi‐disciplinary brainstorming team with adequate experience, knowledge, and qualifications. The team will take each risk in turn and identify potential risk reduction measures, including any identified during the risk assessment.

Although the elimination of danger is the ultimate goal, it cannot be easy and is not always possible. A hierarchical approach to risk reduction involves: hazard elimination (the most effective hazard control); hazard substitution (replacing something that produces a hazard (similar to removal) with something that does not create a hazard); engineering controls (these do not eliminate hazards, but rather isolate people from hazards); administrative controls (changes to the way people work.); and personal protective equipment.

When discussing risk reduction and the hierarchy of risk control, it is essential to introduce the concept of the barrier. Barriers are functions and measures designed to break a specified undesirable chain of events. In other words, their function is to prevent a hazard from manifesting itself or mitigating its consequences.

Both control and recovery barriers are elements of the bow tie methodology that will be discussed in depth. The Bow‐Tie method is a risk assessment method that can be used to analyze risk scenarios. It’s named after its shape and contains eight elements: hazard, top event, threats, consequences, preventive barriers, recovery barriers, escalation factors, and escalation factor barriers.

Anyway, all the topics presented up to now will be discussed in detail later, including the concept of ALARP (which represents a critical element of risk management) and risk reduction in a “region of acceptability.”