You want to implement the STPA method into the company workflow. STPA method and its principles is already known. You have identified a pilot project for use. You presented the method to the team and everything looks promising. Now You need to start workshops with a dedicated group of people, on a real example. You need to go beyond and above materials from the internet. You need to start applying the method to the real example. How to start?
Complete a team and kick off STPA Workshops
It’s good to assemble a proper team. We recommend to build it from domain experts and end users. Could be that STPA leader plays a role of a domain expert, or end users. Let’s say your team is already completed. You find out, on which part of project You want to implement the method in. You want to follow methodology steps. So You define the losses and hazards. This step is relatively easy, everyone agrees about the potential losses and hazards. That was a good warmup. Uphill road starts with the step 2: Establish control structure.
Guide, don’t dictate.
As a STPA leader, You should know all the steps, and understand the methodology. It’s good to be familiar if not fluent with STPA Handbook, or at least check our STPA White paper. You want to challenge domain experts and end users with questions. You should play a role of mediator during the discussion. Both perspectives are very important.
Domain experts create and establish the boundaries of the physical capabilities of the system. They look from technical perspective, what is physically possible to achieve. Their perspective create endpoints and boundaries. End users present what they need, to be able to effectively operate the system, adjust the missions, and collaborate with the system. This is more of a wishlist, how the system should operate.
Remember that workshops are not a presentation. You should be leading, but you should be a listener for 80-90% of time. Role of the STPA leader is to moderate and keep people involved, not dictate the pace. If You see that someone is quiet, ask a direct question to this person, what is his opinion about discussed point. Some people are shy, and need a bit of motivation to share their thoughts. But this is a goal of a workshop, to collect all points of views. This should help us with mitigation of all the risks.
Create a collaborative environment
Role of STPA is to find potential system flaws, and mitigate the risks. Role of STPA leader is to find a balance on what is needed and what is achievable with todays technology. That’s clear that there will be compromise between both worlds. So asking a good question, is a key part. It’s not enough to ask why you need this or that control action. It’s good to challenge people.
Example: If domain experts say that certain type of control is not possible, but final users say that this is important You can make a scenario: This control action is not possible, how otherwise you would imagine to control certain process? Or in opposite direction You can challenge domain experts, what technology development must be implemented to make this control action available?
It’s good to play with both teams. Create a discussion, and sometimes find the way around, to solve the issues. If there is too much tension between the group, it’s a good trick to switch the roles of people. Domain Experts should become end users, and opposite. This should help both groups to better understand others point of views. This is not easy to find a sweet spot of collaboration, but it’s important to keep people engaged.
Keep Team focused during STPA Workshops
It’s good to change the steps, from control structure to identification of Unsafe Control Actions. Why? Believe me, discussions about the control structures, are never ending stories. So after 30-40% of time planned for 1st session, I suggest to move to step 3. Of course, only for the actions which everyone agrees on. Do analysis of a certain scenarios, according to the methodology. ( Providing action leads to hazard, not providing action leads to hazard, providing in wrong time/order, providing too long/too short).
When You identify and discuss all the flaws, team would understand better, what they are actually doing. Then it’s good to find a place for a quick coffee break, and implement potential findings on the control structures. You can potentially go back to discussion on missing points in the control structures, to see if team can make any progress. If You have good results during 10 minutes, continue. If not, just switch back to step 3, and do analysis on next control action. (Again, follow the methodology). Change the steps between step 2 and step 3 is quite natural. You find new issues, You want to implement new solutions to close the gaps. You control structure evolves. Your STPA Workshops are working.
Manage time
As STPA leader You are in control of the workshops, their frequency and planning. I recommend to go with 2-3 hour sessions. This will help to keep people involved, and have efficient use of their and your time. Amount of sessions during the week, depends on the project complexity.
If entire project connects several domain, it might be a good idea to have several STPA streams running in parallel. You can have same end users, and different domain experts involved.
Try to control the time during workshops, do a quick recap from previous week and explain what You plan to achieve at the beginning of each meeting. Do a break in the middle of workshops (5 minutes is enough). Try to finalise discussion 5 minutes before the end of workshops, to summarize the day, and potentially schedule the next workshop date. Rotate between the method steps to keep people involved.
Create a clear documentation
From our experience, that’s the most difficult step. Especially at the beginning. You need to find a balance between leading the workshop and taking a notes. Right notes, in the right places. We have a dedicated templates for that, but it’s not easy if You are just starting to work with the method. The best solution then is to create yourself a tables (Examples are in STPA Handbook). Try to organize your notes after each session. At the next stage, You will prepare a
Plan post STPA workshops activities
If You are creating entire documentation of the process, then You need to plan your time. If other participants are responsible for creating a simulation scenario, or example for a discussion for the next workshop, this tasks should be clearly distributed. Can be in the form of the minutes of workshops, that everyone remembers what You have agreed on.
To summarize, most important points for STPA Leader:
- Build a team. Domain Experts + Final users + Method Leader = Good results
- Guide team with good questions, challenge them with examples
- Follow the methodology
- Invite everyone to discussion, ask directly about the opinions on discussed points
- Care about collaboration, moderate if necessary
- Respect scheduled time, keep people focused
- Document all the discussions, correct your notes afterwards
- Distribute tasks, with clear notes after each session
