TS 296

TS 296 is a standard that brings together the naming of mechanical quantities and their corresponding units within the SI system, along with the associated symbols, definitions, and conversion factors. Mechanics covers core engineering and physics quantities such as force, mass, length, acceleration, momentum, work, and power, so consistent unit usage is essential for comparable measurement results.

Mechanical quantities within the SI framework

The focus of this standard is the consistent use of quantity names and unit designations in mechanics. In the SI structure, the quantity, its unit, and the unit symbol are distinct elements; the same physical concept may be expressed through different derived units depending on context. This framework provides a common language for technical drawings, calculations, laboratory reports, and mechanical engineering practice.

Symbols, definitions, and conversion factors

The three main elements covered by the standard are quantity symbols, definitions, and conversion factors. Symbols and definitions clarify what each term means, while conversion factors help transform values from non-SI or differently scaled expressions into SI-based form. This is especially useful when moving from older unit systems to SI or harmonising data from different sources.

• Provides shared terminology for mechanical quantities and their notation.
• Helps keep SI unit usage consistent in technical documents and calculations.
• Includes conversion factors that support conversion between unit systems.
• Supports comparability in records, reports, and measurement data.

This TS 296 edition was published as equivalent to ISO 31-3:1992 and has since been withdrawn. Even so, it remains a classic reference framework for understanding the systematic classification of mechanical quantities and units in SI terminology.