Safety of people, equipment, facilities and the environment is becoming increasingly important in industrial operations. This is not just because of highly publicised accidents or even for altruistic reasons. Rather, it has become evident that the safety of an operation is directly linked to profitability.
Although it is true that industrial executives are very concerned over the safety of their operations. It’s the increased profitability potential that can be realised through more effective safety management that is really starting to turn heads and to truly bring safety and environmental integrity into the mainstream of industrial business processes.
For decades, industrial professionals have recognised that the cost of unexpected events, such as fires or explosions, can be very high in terms of injury, death, equipment damage, facility damage, environmental damage, business interruption, and insurance. Industry has responded to this high potential cost through functional safety programmes, such as installing safety instrumented systems to detect pending unsafe conditions and automatically taking the correct response. These systems have proven to be very effective at the avoidance of predefined unsafe events and certainly represent a huge step forward. But cost avoidance of unexpected events represents just a small piece of the overall potential profitability impact that may results from an effective safety control solution. The ‘cost avoidance’ perspective tends to be too easy for business executives to turn a blind eye to, because they are lulled into believing that unsafe events will hit other businesses and not theirs. Unfortunately this tends to be an all too human thought process for all kinds of similar events, which seems to have served to inhibit capital spending on safety improvement initiatives.
All executives have a keen interest in is profitability and most are willing to invest in approaches that measurably improve profitability. What may not be totally clear is the impact operational and functional safety control can have on profitability even in the absence of costly unsafe events. It has often been difficult for Environmental, Health & Safety (EH&S) leaders to get funding for the capital projects they propose because the ‘payback’ is not obvious. But the payback for a systematic approach to operational and safety management and control can be huge. Industry needs a new way of thinking about, measuring and improving safety.
Real-time variability and profitability
Over the past decade, key industrial business variables, such as the price of energy or raw materials, have transitioned from highly stable over long periods of time to high variability within a day or even an hour. This shift to real-time variability of industrial business variables presents daunting challenges to industrial executives. A number of key components of the profitability of an operation, such as production value, energy cost and material cost are fluctuating more and more frequently with time. These three variables can be considered the real-time vector components of profitability. The primary object would be to maximise the production value of the operations while simultaneously reducing the energy and material costs by as much as possible.
Balancing these three variables to maximise the profitability of the operation is a fairly classic control problem, which is why it is referred to as real-time profit control. To solve such a control problem requires a classic control approach.
The impact of safety on real-time profitability
There are constraints on the profitability that limit the length of the vectors and the overall profitability of the operation. For example, the installed manufacturing equipment itself will provide some limits, such as the capacity of a pump, the size of a vessel or pipe, and the efficiency of a unit. Most constraints are fairly easy to identify and are fixed. But there is one constraint set that tends to fluctuate in real-time. That constraint set is safety (people, process, environmental). The actual real-time profitability model should include the safety constraint as there is a tight relationship between operational safety and real-time profitability.
Since many industrial operations are very safety focused, the safety constraint is typically a tighter constraint on the profitability of the operation than other constrains, such as physical equipment constraints. Also, since safety risk is seldom directly measured, most industrial plants assume the risk is greater than it may truly be and operate in a more conservative manner than necessary, limiting profitability. Therefore, if the safety constraint functions can be expanded, the operation can be driven harder in order to increase profitability. One key to improving operational profitability, therefore, is the opening of the safety constraint on the profitability.
Opening the safety constraint
The key to being able to determine where the safety constraint truly is and how to free it up is to measure accurately the safety risk of a piece of equipment, process unit, plant area or plant in a real-time, continuous manner. With ongoing real-time measures of safety risk, plant operations can determine how hard they can safely drive the plant. Without the real-time safety risk measures, when circumstances around the operation combine to increase the safety risk, that increased risk often goes unnoticed. This results in not only a less profitable operation, but also a less safe operation.
The deployment of continuous, real-time safety risk measures is the key to controlling the safety constraint. This can be accomplished by developing a dual view of safety risk and combining this dual view into composite safety risk measures. The first view of safety risk, operational and compliance safety risk, involves following the processes and procedures with respect to inspections, audits, and reviews determined during the design of the plant. These audits should be accomplished on a defined schedule to ensure that the operational and compliance risk are as low as possible. History has demonstrated that operations that follow the compliance audits judiciously tend to have much lower safety risk.
The second view of safety risk, conditional safety risk, involves online condition monitoring and measuring. Unexpected events and conditions that cannot be discerned during an inspection can develop to drive up safety risk. The information necessary to discern increases in the probability of an unexpected, unsafe event should be readily available for any plant with a reasonable operational history. The aspects of the conditions that might lead to an event can be monitored to detect any suspicious changes. Automatic workflows can be triggered that further assess the situation, increase the conditional safety risk measure according to the probability and severity of a potential event, and advise the operating personnel.
Since having two separate safety risk views and corresponding measures increases the operational difficulty of assessing the actual safety risk and could lead to confusion, a composite safety risk measure for the operation should be developed. This composite measure should take the operational and compliance safety risk measure and conditional safety risk measure as inputs and perform appropriate analytics on the two measures to establish the actual current safety risk. The composite measure should be heavily weighted to the higher of the two input safety risk components. It might be easy to merely take the higher of the two component risk factors, but this approach may be too simplistic for complex production operations. Some operations will require an analysis of both component measures against each other to develop the composite safety risk measure of the operation. With this real-time safety risk factor for every operation in the plant and for the plant as a whole, the operating personnel can make decisions that improve plant profitability while understanding the impact of their decisions on the safety risk in the plant.
Real-time safety risk control
For operational and compliance safety risk issues, controls can be applied by keeping the operational safety risk measurement visible to the leaders of the EH&S team responsible for the safety compliance audits, and, if significant violations of expected processes are encountered, to automatically notify plant management of the violation. Automatically triggered workflows can also be developed in the system that trigger workflows to notify and guide the compliance processes and to keep management in the loop when the processes are correctly followed as well as when there may be an issue. This level of feedback sets up a manually operational and compliance safety risk control system that will certainly help to reduce the safety risk of a plant.
A similar approach can be taken to the conditional safety risk of the operation, although conditional risk is typically less dependent on human processes than it is on unexpected failures and other unanticipated events. For the conditional safety risk a predictive conditional safety system can be developed using automatic workflow to monitor for a potential safety condition, identify the condition and take the appropriate corrective action. All components of this conditional safety risk control system can be set up for automatic operation.
Setting up the correct safety conditions monitor involves a detailed understanding of the history of operation of the plant and of other similar plants. Historical data must be analysed to identify the lead indicators of an unexpected event and must set up the safety condition monitor to trigger from these lead indicators. A corrective action function must be set up to take various corrective actions based on the circumstances identified for the potential event. This is not unlike the approach to safety taken with traditional batch service logic for decades, but this perspective must be taken for the plant as a whole.
Real-time profitability control
Opening the safety constraints on a production operation does not, by itself, lead to increased profitability. It merely means that there may be potential to increase profitability safely. Actually driving increased profitability requires the application of control theory to the three variables of real-time profitability. This can be accomplished through a manual feedback control system driven by contextualised profitability dashboards for each operator. The issue of tying the safety risk measure and the profitability controls together is as simple as providing a real-time safety risk indicator on the operation profitability dashboards. This visible real-time safety risk value will provide immediate feedback to the operators of the increased or reduced safety risk resulting from any actions they take. This enables operators to take appropriate profit improving actions while simultaneously mediating safety risk. In a sense, simultaneously balancing safety risk, production value, energy cost and material cost this is tantamount to solving a multiple objective optimisation problem. Mathematically solving this type of problem is very challenging and time consuming, but experience has demonstrated that an operator with a moderate educational level and reasonable experience can learn to solve such a problem quite effectively over time.
Summary
Traditionally, safety and profitability have appeared to be diametrically opposed concepts for many manufacturing and production operations. Since the primary objective for any manufacturing or production business is to drive profitability, the safety of people, plant and environment have often been viewed as somewhat necessary evils. As such Environment, Health & Safety (EH&S) teams in industrial companies have typically been viewed as adjunct organisations that are not part of the main stream business. Such positioning has made their job more challenging. Fortunately, the state-of-the art in control theory is leading industrial companies in a different direction with respect to safety. The safe operations of industrial plants are now understood to be a direct factor in the profitability of those plants. ES&H can be turned into a mainstream business process of industrial companies and new levels of both safety and profitability can result. Real-time safe profitability is no longer a dream – it is a reality!
For more information contact Jaco Markwat, Invensys Operations Management, +27 (0)11 607 8100, [email protected], www.iom.invensys.co.za
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