Clause 6.3.3.4: Develop the operational concept
The process defines a representative set of scenarios that cover the required capabilities and the anticipated operational and life cycle concepts.
What clause 6.3.3.4 asks
The process defines a representative set of scenarios that cover the required capabilities and the anticipated operational and life cycle concepts. It identifies how users and the system interact and the factors that affect those interactions, including the workplace, normal and unusual conditions, and the users' skills and knowledge. Human systems integration is brought in here: staffing, skills, training, ergonomics, working environment, health, safety and living conditions are considered together with the technology.
Why it matters
The operational concept is the bridge between needs and requirements. Scenarios are how the concept is tested: a capability that no scenario uses is either unnecessary or missing from the concept. The human systems integration paragraph is easy to skip and expensive to retrofit, because usability and training requirements depend on it.
No clause level change is public for this unit; the DIS keeps the title and scope, and the requirement text is not released.
What good looks like
Write the concept in the users' language. Build a scenario set that covers normal, degraded, emergency and maintenance use. For each scenario, note the users, the environment, the information and the decisions. Then derive the interaction requirements.
Evidence an assessor asks for
The assessor will ask which scenario justifies a capability, and which capability no scenario uses. Both answers expose gaps.
- Operational concept The users, environment, modes, capabilities and constraints, in the users' language
- Scenario set Normal, degraded, emergency and maintenance scenarios, with the capabilities each exercises
- Interaction analysis The user-system interactions and the factors that affect them
- Human systems note The manpower, training, human factors, safety and health considerations
Where it commonly fails
- The operational concept is a system architecture diagram with no users in it
- Only the happy path is described, so degraded and emergency modes are designed later
- Usability is left to the interface team after the requirements baseline
What to do before the revision
Add a scenario coverage column to the requirements register. A requirement with no scenario needs a reason to stay.
Read across
- 5.2.3 Transformation of needs into requirements
- 6.3.3.3 Define stakeholder needs
- 6.3.3.5 Transform needs into stakeholder requirements
- A.2.6 OpsCon: concepts for the proposed system
← 6.3.3.3 Define stakeholder needs 6.3.3.5 Transform needs into stakeholder requirements →
Source for clause 6.3.3.4: ISO/IEC/IEEE 29148:2018, Clause 6.3.3.4, retrieved 19 October 2026. The revision note rests on ISO page 94091. The requirement, evidence and gaps are written from our record. Every source.