1.0 Hazardous conditions:
Natural hazards such as flood, Fire etc. cannot be anticipated totally and accurately, but reasonable preparedness against these is expected as called for.
Additionally there have been increasing possibilities of hazards due to human factors on account of the following reasons:–
Industrial functions are being carried out at ever increasing levels of pressure, temperature and speed and machine or carrier failures often take place where either designed factors of safety and safe considerations are not adequate or where operational or component failure may take place.
There is more and more infusion of technological tools and apparatus in the hands of common man who may overlook the basic operational or safety rules prescribed by the supplier or manufacturer.
New discoveries of Energy conversion procedures are being made and these may present operational challenges not foreseen clearly and operational errors may take place.
Encroachment or invasion of large number of semi -skilled, or unskilled, or ill informed, or recklessly adventurous humans who venture in the nature’s unknown depths without adequate safety preparations and get involved in hazardous situations calling for organized rescue operations.
Defiance and disrespect of rules in general e.g. smoking at prohibited places and throwing cigarette subs on flammable medium.
Due to the above factors the possibilities of Hazards and disasters are increasing and predictability of where and how these will strike is reducing.
It is said that the hazard is omnipresent. If it is so, why are we so much concerned with it?
There are three important factors which decide about hazard and with minimum its minimum effect of damage.
First is, to correctly identify hazardous condition and hazardous environment in the very initial stage. (Hazard Identification)
Secondly, to assess accurately the gravity of the hazard so that appropriate tools, instruments, methodology can be applied for mitigation. (Risk Assessment)
The third, the most important and often ignored factor is that, based on the assessment of the hazard, correct decision needs to be taken, whether or not to press the panic button and to what extent one needs to go into panic mode. (Quantum of risk – can be both qualitative and quantitative)
More clarity will come through following discussions.
2.0 Risk – how is it different from Hazard:
After danger and hazard, the word which we come across is RISK. When we refer to risk in relation to occupational safety and health the most commonly used definition is 'risk is the likelihood that a person may be harmed or suffers adverse health effects if exposed to a hazard’.
In simple terms, risk is the possibility of something bad happening. Risk involves uncertainty about the effects/implications of an activity with respect to something that humans value (such as health, well-being, wealth, property or the environment), often focusing on negative, undesirable consequences.
As for example –
Water is a hazard nut jumping into water (lake, pond, river, sea etc.) without knowing how to swim is risk
Driving a vehicle is full of hazard but talking on a mobile phone or texting or over-speeding is the risk.
Risk is defined as the combination of severity and probability of occurrence of an event. Hence, we can say, Risk is proportional to two factors –
Probability or Likelihood of an occurrence or incident, which would cause a harm and
The amount of Severity likely to get associated with this harm
Pictorially, it would look like this –
3.0 Positive and Negative Risks:
Risk can be both Positive as well as Negative.
A negative risk is a threat, and when it occurs, it becomes an issue. However, a risk can be positive by providing an opportunity for your project and organization. This is critical to consider while registering the risks. This is like a two side of a coin.
This also means –
POSITIVE RISK creates an opportunity for us. Hence, we should not avoid it but enhance and get use of it as it brings a positive outcome and results in success.
NEGATIVE RISK being a threat to us and may result into a negative outcome or failure, shall be either avoided or mitigated.
4.0 Quantum of risk:
Quantum of risk – can be both qualitative and quantitative. Irrespective of these, based on the calculation, Risk can be categorized as High, Medium and Low.
Qualitative Risks is nothing but the perception of a risk. It uses subjective judgment to determine the probability of a risk occurring and its impact on an organization. As for example, the lack of machine guards was initially given a risk rating of low, but after several near misses involving the hazard occurred, the manager or the supervisor felt that its risk rating should be at least medium. Here, the risk is decided by the perception of the concerned persons.
Quantitative risk analysis is an objective, data-driven process to evaluate the impact of an identified risk on the overall project plan. Decision tree analysis, estimated monetary value, three-point estimate, and Monte Carlo analysis are examples of quantitative risk assessment. Here, more than perception, calculated data, mathematical models etc. play an important role. Quantitative risk assessments are specialized hazard and safety studies. The impact of major events such as explosions, fires or unplanned emissions of gas, can be modeled using sophisticated simulation software. These techniques may be described as quantitative risk modeling.
5.0 Qualitative Method of Risk Calculation:
As we have seen, risk is proportional to two factors –
Probability or Likelihood of an occurrence or incident, which would cause a harm and
Consequence of hazard or the amount of Severity likely to get associated with this harm
Hence, mathematically it can be expressed as -
Risk ∝ (Probability of the happening of the incident) X (Severity likely to result in)
Often, a 3rd variable “Detection” is also considered. For the time being, if we ignore the other variables like “Detection”, we even can say –
Risk = Frequency of the occurrence x Consequence of hazard (or severity)
Risk as can be seen from the above empirical formula is directly proportional to both, the frequency and the consequence of hazard. Aiming to reduce frequency of occurrence is more desirable than aiming to reduce the consequence of hazard since all events are likely to have cost implications even without dire consequences. To minimize risk, we must reduce frequency or the consequence or both. If we can’t take away the hazard we shall have to reduce the risk.
6.0 Risk Priority Number (RPN) and Action Priority (AP):
To find out the quantum of the risk, we can allot some number (say 1 to 5) to these two probabilities. Please keep in mind risk can never be zero. Hence, we have to choose a whole number other than zero.
Thereby, we get two sets of number matrixes:
By multiplying, we get the following whole numbers –
1,2,3,4,5,6,8,9,10,12,15,16,20 and 25
These numbers are called Risk Priority Number or RPN. (Please note, you can have 3 sets of numbers also by including “Detection”)
By applying our perception of a risk to this RPN, we can categorize the risks as –
LOW Risk – 1,2,3,4,5,6,8
Medium Risk – 9,10,12,15
High Risk – 16, 20, 25
We need to bring down the quantum of risk by reducing the RPN by controlling both frequency and consequences. However, risk categorization based on the RPN has a major disadvantage. Let us try to understand the figure below, where a person is passing over a pit and the table beside it, which reflects the RPN of the corresponding activities:
In the sketch 1 - where probability is very high, a number 5 may be allotted and as the impact is low, the allotted number is 1. This makes the RPN as 5. Similarly, in the Sketch 3, probability is low but consequence is high but RPN is 5.
Bothe cases, RPN is same. But, the activity in the Sketch 3 looks more dangerous. To overcome, this type of situation, the present concept is to replace Risk Priority Number (RPN) with Action Priority (AP). AP was developed in order to give more emphasis to Severity first, then Occurrence, and then Detection. You can choose to use RPN or AP or both.
We can easily get Action Priority (AP) by using the Action Priority Matrix, which is a simple tool that helps us to choose which activities to prioritize. The matrix below has twenty five quadrants distinctively indicating HIGH, MEDIUM and LOW Risks. The use colour RED for High Risk; YELLOW for Medium Risk and GREEN for LOW Risk as made in the diagram below helps us to make best use of the mitigation techniques available to us.
Once we are thorough with colouring, we can determine the risk acceptability. Red indicates ‘Generally Unacceptable’; Yellow is as Low as Reasonably Practical (ALARP) or Low as Reasonably Acceptable (ALARA) and Green is ‘Generally Acceptable’.
Our attempt shall be to bring down the High Risk (GU) to Medium Risk (ALARP/ALARA) and the Medium Risk to Low (GA) by incorporating various mitigation measures.
7.0 Risk Appetite and Risk Tolerance:
There is a strong relationship between Risk Tolerance and Risk Appetite. Risk appetite is the level of risk that an organization is willing to accept while pursuing its objectives, and before any action is determined to be necessary in order to reduce the risk. Risk tolerance is the degree of risk or uncertainty that is acceptable to an organization.
Risk tolerance is the level of risk that an organization can accept per individual risk, whereas risk appetite is the total risk that the organization can bear in a given risk profile, usually expressed in aggregate.
The ALARP principle recognizes that there are three broad categories of risk tolerance:
Negligible risk: Broadly accepted by most people as they go about their everyday lives, these would include the risk of being struck by lightning or of having brake failure in a car.
Tolerable risk: We would rather not have the risk but it is tolerable in view of the benefits obtained by accepting it. The cost in inconvenience or in money is balanced against the scale of risk and a compromise is accepted. This would apply to traveling in a car, we accept that accidents happen but we do our best to minimize our chances of disaster. Does it apply to bungee jumping?
Unacceptable risk: The risk level is so high that we are not prepared to tolerate it. The losses far outweigh any possible benefits in the situation.
One of the difficult aspects in implementing the ALARP principle is to define the three levels of risks.
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