Single Source of Truth

A Single Source of Truth (SSOT) is a concept where a defined system, database, or repository is treated as the authoritative place to store and retrieve a specific set of information. In industrial and manufacturing environments, it is used to reduce conflicting data, duplicate records, and inconsistent versions of critical operational and compliance information.

What it includes

In practice, a Single Source of Truth typically refers to:

• A designated system of record for a data domain, such as product master data, equipment hierarchies, recipes, or material specifications.
• A controlled repository for regulated or versioned documents, such as SOPs, work instructions, batch records, or quality procedures.
• An agreed business rule that other systems should consume data from this source rather than maintain independent copies for the same purpose.

The SSOT can be implemented in different technologies, for example:

• ERP or PLM as the SSOT for product and material masters.
• MES as the SSOT for production event data, genealogy, and in-process quality records.
• Document management or quality management systems as the SSOT for controlled documents and records.

What it does not mean

Having a Single Source of Truth does not mean:

• Only one physical database exists in the entire organization.
• Other systems cannot store or cache data. They may hold copies, but those copies are derived from and reconciled with the SSOT.
• All data types must share the same source. Different domains, such as finance, maintenance, and production, can each have their own SSOT.

Operational meaning in manufacturing

In operations and manufacturing systems, a Single Source of Truth commonly appears as:

• The master reference that feeds synchronized data into MES, LIMS, historians, and other OT and IT systems.
• The official location auditors and inspectors are directed to for current specifications, procedures, and records.
• The system that owns the lifecycle of a dataset or document, including creation, approval, version control, and retirement.

Clear SSOT definitions support consistent production parameters, accurate traceability and genealogy, and aligned reporting between shop floor systems and enterprise systems.

Common confusion

Related terms are often used alongside Single Source of Truth:

• System of record: A system formally designated to be responsible for maintaining the authoritative record for a specific data type. It is often the SSOT for that domain.
• Golden record: A cleansed, consolidated version of a data entity, such as a material or supplier, often created by master data management processes that implement the SSOT.
• Data warehouse or data lake: These can aggregate data from many sources for analytics but are not automatically the SSOT for the underlying operational data.

Use in regulated and quality-focused environments

In regulated manufacturing, the idea of a Single Source of Truth is frequently applied to ensure that:

• Only one approved version of controlled documents is used on the shop floor.
• Quality records, deviations, and CAPA information are retrieved from an agreed system.
• Evidence for inspections, audits, and investigations is pulled from traceable, authoritative systems instead of ad hoc spreadsheets or local copies.

Organizations typically define SSOT responsibilities as part of their data governance, document control, and integration design so that OT, MES, ERP, and quality systems reference consistent information.