Till now, we have come across many reasons why an engineer needs to be responsible. The responsible engineers follow the codes of ethics to avoid unnecessary problems. The problems majorly occur in two different ways. One of them is when you can assess and the other is when you cannot. A mistake made by an engineer at work may result in huge losses.
An engineer is supposed to assess the risks of his experiments. The disasters do occur at times, though enough care is taken, as stated in the examples given in previous chapters. But knowing all the possibilities, if an engineer neglects the precautions, the results can be really disastrous. So, let us try to analyze the importance of safety in engineering.
The terms of safety and risk are inter-related. It is amazing to know that what may be safe enough for one person may not be for someone else. It is because of either different perceptions about what is safe or different predispositions to harm.
For better understanding, let us explore safety and risk further.
According to William W Lowrance, the famous consultant of those times, Safety was defined as “A thing is safe if its risks are judged to be acceptable.”
To be more clear on this, let us consider three cases.
Let the first case be where we seriously underestimate the risks of something. Buying a non-brand electric dryer from a local market without any guarantee, may eventually send us to a hospital with a severe electric shock or burn. While buying this dryer, according to Lowrance definition, this is quite safe, as the risks are judged to be acceptable.
Let the second case be where we grossly overestimate the risks of something. If we suddenly know that the consumption of carbonated beverages like cola are the cause of cancer for 5% of the world’s cancer patients, then we start worrying considering Cola as a poisonous drink. So, in this case, according to Lowrance definition, the Cola becomes unsafe the moment we judged the risks of using it to be unacceptable for us.
Let the third case be a situation wherein, a group makes no judgment at all about whether the risks of a thing are acceptable or not. As defined by Lowrance, this is the position where the thing is neither safe nor unsafe with respect to that group. Just like using the products of certain brands are considered safe, while others are not where nothing seems to differ.
Safety is frequently expressed in terms of degree and comparisons. The words like fairly-safe and relatively-safe are used where an individual is judged on the basis of settled values and it is further decided that the risks of anything are more or less acceptable in comparison with the risks of the other thing. For example, the consideration that roadtravel is safer than air-travel.
Any work which might lead to harm us and is not considered safe, can be understood as a risk. According to a popular definition, “A risk is the potential that something unwanted and harmful may occur.” According to William D Rowe, potential for the realization of unwanted consequences from impending events.
Risk is a broad concept covering many different types of unwanted occurrences. When it comes to technology, it can equally well include dangers of bodily harm, of economic loss or of environmental degradation. These in turn can be caused by delayed job completion, faulty products or systems or economically or environmentally injurious solutions to technological problems.
With the advancement in technology, people are now aware of all that goes into a process. Further, risks are understood as those that can be identified. Overall, the public perception has also undergone a change.
Lowrance in his definition observed safety as acceptable risk. Let us relate to this and further see the definition by William D. Rowe, “a risk is acceptable when those affected are generally no longer apprehensive about it”.
Influential factors that lead to such apprehension are −
Whether the risk is accepted voluntarily.
The effects of knowledge on how the probabilities of harm (or benefit) are known or perceived.
If the risks are job-related or other pressures exist that cause people to be aware of or to overlook risks.
Whether the effects of a risky activity or situation are immediately noticeable or are close at hand.
Whether the potential victims are identifiable beforehand.
The acceptability of risk depends upon the types of risks such as voluntary and involuntary risks, short term and long term consequences, expected probability, reversible effects, threshold levels for risk, delayed and immediate risk, etc.
Let us have a better understanding on the acceptability of risks in our subsequent sections.
In our daily life, we come across many such things where the scopes of risk might or might not be low. The person who breaks a red signal, is prone to be a victim of an accident, but risks. A person who lives near a dumping yard is prone to ill-health, but neglects. A boy who rides a vehicle at a high speed cannot rely on the perfect functioning of the brakes. But these people take voluntary risks thinking they can control.
In this manner, they may well display the characteristically unrealistic confidence of most people when they believe hazards to be under their control. Enthusiasts worry less about the risks they might face and hence neglect the dangers behind them. The chance of getting affected is unpredictable in such cases.
The acceptance of risks also depends on the manner in which information necessary for decision making is presented. A person can be motivated to violate the safety rules by explaining the higher probability of success, whereas the same person can be demotivated from such task, by explaining the probability of failure and the fatal effects of it.
Hence, options perceived as yielding firm gains will tend to be preferred over those from which gains are perceived as risky or only probable. Emphasizing firm losses will tend to be avoided in favor of those whose chances of success are perceived as probable. In short, people tend to be more willing to take risks in order to avoid perceived firm losses than they are to win only possible gains.
In some jobs where the workers are exposed to chemicals, radiations and poisonous gases etc., they are not informed about the probable risks the workers would be facing, in doing their jobs. These are such dangers where the toxic environments cannot readily be seen, smelled, heard or sensed otherwise.
The workers at such places are simply bound to their work and what they are told to do. The health condition of a person who gets affected under such environments cannot be neglected because that will be the future condition of co-workers.
It is unfortunate that most of us, realize the magnitude of risk only when we ourselves or the person who is in our close proximity or a relative, gets affected. A group of 20 friends including us, if gets affected or if had a narrow escape from death, affects us more than the incident occurred to a group of 50 strangers, in a group of a 1000. This proximity effect arises in perceptions of risk over time as well.
A future risk is easily dismissed by various rationalizations including −
The attitude of “out of sight, out of mind”.
The assumption that predictions for the future must be discounted by using lower probabilities.
The belief that a counter-measure will be found in time.
A continuous enthusiasm that fosters us to do such task without thinking is really dangerous. Either the attitude that everything is under control and nothing is going to happen or the negligence upon the number of accidents occurred is equally risky. It is important that engineers recognize as part of their work such widely held perceptions of risk and take them into account in their designs.
The study of risk analysis covers other areas such as risk identification, risk analysis, risk assessment, risk rating, suggestions on risk control and risk mitigation. In fact, risk analysis can be deeply discussed with a view on risk management study. The risk management study also includes residual risk transfer, risk financing, etc.
A step-wise risk analysis includes −
Failure modes and frequencies evaluation from established sources and best practices.
Selection of credible scenarios and risks.
Fault and event trees for various scenarios.
Consequences-effect calculations with work out from models.
Individual and societal risks.
ISO risk contours superimposed on layouts for various scenarios.
Probability and frequency analysis.
Established risk criteria of countries, bodies, standards.
Comparison of risk against defined risk criteria.
Identification of risk beyond the location boundary, if any.
Risk mitigation measures.
All of these again depend on how the risk is compared with the benefit in doing the work with some risk. How far it is beneficial to risk also counts the actions of a person while coming out of the safety bounds.
As per the famous saying, “A Ship in harbor is safe. But that’s not what ships are built for” risk is somewhat common to be accepted. The most common risk we all take is driving an automobile in a traffic. Though we are not sure about the perfect functionality of the brake system and the timings of other drivers’ responses, we take risk. The controlling factor appears to be their perception of their individual ability to manage the risk-creating situation.
Just like the above instance, people mostly calculate the ratios of risk to benefit, while accepting the risks. The risk to benefit analysis is made depending on the types such as the ones mentioned below.
The risk to be occurred in future is completely known after it gets fully developed. It is called as Real future risk.
If the idea of risk is developed using current data, such one is called as Statistical risk.
The risk which is analytically based on system models structured from historical studies is called as Projected risk.
The risk which is intuitively seen by individuals is called as Perceived risk.
If risks of traveling on an air-plane is considered for observation, then the flight insurance. company can observe it as a statistical risk, while the risk the passenger faces is Perceived Risk and the Federal aviation administration, faces a Projected risk. Hence, the view of accepting the risk and the idea of risk to benefit ratio motivates the individual.
The risks we generally face can be reduced to a great extent by proper analysis with steps. as mentioned below −
The risk management has to be viewed in a wider angle at times when sudden disasters occur due to lack of proper care and assessment. The government which has the responsibility to take care of all the public needs to take some risk. The government’s approach towards the public lies in saving as many lives as possible.
The two major approaches of the government are −
Lay person − Wants to protect himself or herself from risk.
The government regulator − Wants as much assurance as possible that the public is not being exposed to unexpected harm.
For example, at the times of flood or some fire accident, the government of any place should aim at protecting as many lives as possible rather than looking for a benefit or protecting some property. It will count as a successful attempt towards facing risk if the authority is able to protect its people even after the destruction of property.
6 Lectures 1 hours