Requirements are documented needs, obligations, or expectations that specify what a system, product, process, or organization must achieve or comply with. In industrial and regulated manufacturing environments, requirements are the formal basis for design, production, quality control, and compliance activities.
What requirements typically include
In manufacturing and industrial operations, requirements commonly refer to:
- Technical and product requirements: Specifications, drawings, tolerances, materials, performance criteria, and functional characteristics that a product or component must meet.
- Process and procedural requirements: Defined steps, methods, parameters, and controls for how work is performed (for example, standard operating procedures, work instructions, process recipes).
- Regulatory and standards requirements: Applicable laws, regulations, and external standards that must be met (for example, industry standards, safety codes, or quality management requirements).
- Customer and contract requirements: Commitments agreed in contracts, purchase orders, statements of work, or customer-specific specifications.
- System and software requirements: Functional and non-functional needs for MES, ERP, SCADA, or other OT/IT systems that support operations.
Requirements are usually traceable documents or records. They are referenced throughout the lifecycle, from design and planning through production, inspection, release, and change control.
Operational role of requirements
In day-to-day operations, requirements commonly serve to:
- Define criteria for acceptance or rejection of materials, components, and finished goods.
- Provide the reference point for inspections, tests, and in-process checks.
- Guide how work instructions and recipes are authored and updated.
- Support traceability from customer or regulatory expectations down to plant-floor actions.
- Enable impact analysis when changes are proposed to products, processes, or systems.
Relationship to nonconformities
A nonconformity is typically defined relative to requirements. An issue is considered a nonconformity when there is objective evidence that an established requirement has not been met. Without a clear, documented requirement, it is more difficult to classify a deviation as a formal nonconformity.
Common confusion
- Requirements vs. specifications: A specification is a detailed form of requirement, often focused on measurable technical or process criteria. “Requirement” is the broader term and can include specifications, procedures, and contractual or regulatory obligations.
- Requirements vs. design: Requirements state what needs to be achieved, while design describes how those requirements will be met. Mixing the two can reduce clarity, especially for traceability and change control.
- Requirements vs. policies: Policies are high-level organizational rules or intentions. Requirements are more specific and actionable, and are often directly testable or verifiable.
Requirements in OT/IT and MES contexts
For manufacturing IT and OT systems, requirements commonly cover data capture, traceability, system interfaces, security controls, and support for regulatory records. Functional and non-functional system requirements guide configuration and validation of MES, ERP, LIMS, and related systems that support compliant operations.