The assessment is in the form of specific questions, each requiring a yes/no answer (see Figure 1). The questions are arranged in eight trees. The choice of scenarios for assessment is critical and must consider the worst cases both in terms of consequence and of operator workload.
The physical assessment can be summarized from one of the HSE case studies:
The specification of scenarios in terms of the number, type and level of detailed description required, i.e., the need to identify scenarios which could result in incidents with major hazard potential. There should be no fixed rule on the number of scenarios that should or must be analyzed each plant or unit is different. It is recommended that scenarios representing the following are analyzed:
- Worst case scenarios requiring implementation of the off-site emergency plan;
- Incidents which could escalate without intervention to contain the problem on site;
- Lesser incidents requiring action to prevent the process becoming unsafe.
A site will also need to consider whether it is necessary to assess the scenarios at different times such as during the day and at night, during the week and at weekends, if staffing arrangements vary over these times.
It is necessary to define the circumstances of each scenario in sufficient detail. As a minimum:
- Define who is controlling the process and their starting locations;
- Define who is available to support the incident, and their starting locations:
- Define the parameters that determine the time available to the operations team for detection, diagnosis and recovery. 
In practice the physical assessment is only as good as the experience and knowledge of the assessment team. However, with the correct operations input the methodology can be invaluable, allowing a company to meet regulatory requirements and reduce the strain caused by MOC. We are not suggesting that this methodology eliminates the need for using the CMA checklist; we believe the CMA checklist makes the HSE methodology more complete. Two example forms are provided for the physical assessment (Table 1 and 2).
The combination of these two resources really allows a good grasp of the inside/outside job post and the process control operator or console operator post. Our experience has identified a shortfall in both methods and we suggest for the field post that additional study is required to address the issue we mentioned earlier, the time line.
Most field operators have their own dedicated area, but sometimes that area can be made up of several units and can cover a wide physical area. What the other methodologies don’t do very well is consider these time issues and how a team works together. As a minimum, what is required is a time line identifying the who, where and when of each task for each person involved (Table 3).
Table 3. Defining how your operators spend their time is a first step in establishing workflow. (Click to enlarge.)
A better idea would be time-and-motion studies. This method should be favored for batch processes with lots of manual operations. Using this more advanced technique operator walk time or truck travel time from one location would be evaluated. It’s important to include minimum and maximum times and what other resources can be substituted in the event of a conflict. A conflict also may occur because of similar, simultaneous priorities from trains or equipment. In one example, consider the delay in production if the same truck bay is used for the final product and an intermediate — only one truck can be loaded at a time. Common mode failure should also be considered when evaluating the demands on a single roaming operator.
All of this does take time — a learning curve is involved; in practice once the process has been started a team can comfortably do a job position in a day. So if you’re looking at changing six job positions about ten days would be required, to collect common data such as scenarios and then run them through the existing and new job positions.
Passing the torch
The challenge faced by MOC teams is finding time to do these studies correctly and thoroughly. Until a methodology can be employed that balances the workload on existing workers, industry will continue to muddle through MOC — unless the regulators enforce a change. In the U.K., MOOC studies are done for every covered process. A government inspector can turn up at any time to audit a study or complete his own study.
The chemical industry often embraces good practices ahead of OSHA and EPA enforcement. Our studies demonstrate that problems do exist. Industry has evolved jobs haphazardly. We have arrived at position where wide variations in workloads exist between groups of operators, supervisors and managers. People aren’t being used to efficiently man jobs. We have determined that a company may have the right number of people but have them doing wrong things. They aren’t sharing workload and the burden falls on a few.
As an industry we are coming of age so to speak as our seasoned workers will begin to retire in the next five years. Unfortunately it isn’t just operators; it’s also maintenance, supervisors, engineers and managers. A company needs to really understand the impact of what is on the horizon as far as new versus old workers. It isn’t good enough to wait until the crisis is here; companies need to be preparing, planning and hiring workers now. There are other concerns unique to our time in history.
Think of it — all that corporate knowledge is about to be hitting the golf courses and beaches at the same time! Any attractive workers will be on the fast track to promotion and will be very interesting to other companies and competitors. This will eventually end in a price war for employees. We have seen it happen before but we may not have seen it on this scale.
All of this means change, change, and more change and it will benefit a company to have a good handle on MOOC. More than a century ago, the great scientist Louis Pasteur said, “Chance favors only the prepared mind.” By this, he could have meant that sudden flashes of insight don’ts just happen, but are the product of preparation.
To resolve both the MOC and MOOC problems the organization must be prepared for the changes it will inevitably have to experience. The first step, is understanding the problem, the second will be designing the right organization or right-sizing the organization and then having a technique to validate that proposed organization. In our industry we don’t get too many chances to do this, so I suggest we do it properly, which means safely, which also means cost effectively.
1. “Assessing the safety of staffing arrangements for process operations in the chemical and allied industries,” pp. 11, 17, iii and 175, Entec U.K. Ltd. for the Health and Safety Executive — Contract Research Report 348/2001 (2001).
Ian Nimmo is president and founder of User Centered Design Services, Anthem, Ariz., a firm that specializes in abnormal-situation management and other control issues. E-mail him at email@example.com.