Management of Change: Temporary and Infrequent Repeat Changes
Fatality During A Temporary Operation
We continue the process of moving and updating process safety-related posts from our Net Zero site to this Process Safety Report site. This post is to do with the hazards posed by temporary operations.
The Incident
The United States Bureau of Safety and Environmental Enforcement (BSEE) has released a report to do with a fatality that occurred during a temporary operation. The following quotation is from that report.
On May 15, 2021, an incident resulted in the fatality of an offshore worker when two production personnel were pressure testing a 16-inch well surface casing and an explosion occurred. The explosion entailed a high-pressure release with no signs of ignition.
Information obtained by BSEE during the subsequent investigation determined that personnel were using a high-pressure well to supply the pressure to the well casing. They installed temporary test equipment that included a high-pressure hose and a digital pressure gauge, but they did not use the pressure-regulating device and pressure safety valve during the pressure test.
<my emphasis>
The report is available here.
The recommendations in the report identify the following elements of SEMS (the Safety and Environmental Management Systems regulation) as being particularly relevant to this event.
30 CFR § 250.1912 ― Management of Change
30 CFR § 250.1914 ― Safe Work Practices
30 CFR § 250.1912 ― Hazards Analysis (The operator failed to develop and/or implement a hazards analysis and Job Safety Analysis.)
Regarding Management of Change (MOC), the report states,
. . . all individuals <must> follow the company’s MOC policy and procedures when it comes to the installation and operation of temporary equipment.
This observation is particularly important. We don’t know what the people involved said to one another before the incident occurred. Maybe it was something on the following lines,
“This is just a temporary operation ― it won’t take more than a few minutes. We don’t need to go through all this procedural stuff. Let’s just do it”.
Temporary Changes
In our book Process Risk and Reliability we discuss the hazards posed by temporary operations. The following is from the section to do with Management of Change and temporary operations.
Temporary changes are those changes that have a built-in termination date or time. Changes of this type are often implemented to keep an operation running while a piece of equipment is repaired or replaced.
From a safety and operational point of view, whether or not a change is permanent or temporary is merely a semantic matter — the system itself does not know or care that a change is temporary. Therefore, the fact that a proposed change is defined as being temporary does not mean that it can be handled less rigorously than a change that is permanent. Yet, because of the short duration of temporary changes, the personnel implementing them may be tempted to take short cuts, particularly if going through the MOC process takes longer than actually making the change itself. There is a temptation to take an attitude of, ‘Let’s just get on with it — why bother spending hours writing and reviewing a procedure for an operation that will only take a few minutes to carry out?’
An example of a situation that can tempt personnel to take an unacceptable short cut is shown in the sketch.
A hazardous chemical is leaking to the atmosphere through a control valve’s packing. Operations management decides to run a hose bypass around the valve, and to control the flow in the hose using manual valves. The leaking control valve can then be blocked in and repaired.
This repair activity may take no more than 30 minutes. Yet it is a new operation, so the system has changed. Hence, the following steps should be followed:
Conduct a safety analysis ― probably using some type of What-If method. The analysis should focus on the feasibility of controlling the flow of chemical using a manually-operated block valve.
Write a temporary operating procedure.
Train the operators in the new procedure.
Prepare an emergency response plan in case the modification does not work properly.
Make sure that the temporary hose is removed once the repair work is complete, and that all valves are returned to their normal position.
Place blinds on the temporary valves to ensure that there are no leaks through them once the hose has been removed.
These activities could take hours, far longer than the change operation itself, and so could easily engender the response, “Oh, let’s just get on with it — we don’t have time for all this bureaucracy.”
Although it is easy to reproach someone who takes this point of view, it has to be recognized that temporary changes often need to be implemented quickly in order to avoid more serious problems from developing. Indeed, many temporary changes are also emergency changes.
Infrequent Repeat Changes
It is important to distinguish between true Temporary Changes and those changes that have occurred at least once before and that are repeated at infrequent intervals. Such changes are “Infrequent Repeat Changes.” If the change has been carried out before, and if it was properly managed, then, strictly speaking, it does not need to be put through the Management of Change system when it is carried out a second time.
This approach to the management of infrequent repeat change is only valid, however, if the change was properly controlled and documented. If the records are inadequate or incomplete then the Management of Change process will have to be implemented a second time. People may have memories as to what was done, but this is not sufficient; the information must be written down. Moreover, if the change has not been implemented for some time, there is a good chance that not all of the current personnel will have been trained to operate the facility in the new mode. Hence, in this situation, it is best to treat the change as if it is entirely new, and to train people once again.
