TS 1844

TS 1844 defines the symbols used for projection methods in building drawings. The standard addresses two core projection conventions: direct orthographic projection and first-angle reflected orthographic projection. Its purpose is to make the arrangement of views on technical drawings unambiguous, so that a drawing can be interpreted correctly by different users.

Why projection method matters in building drawings

Building drawings commonly combine plans, elevations and sections. The projection method determines how those views are positioned relative to one another on the sheet. In general technical drawing practice, orthographic projection is the method used to represent a three-dimensional object as a set of two-dimensional views, while the choice between projection systems affects the placement logic of those views. That distinction is important for drafting, reading and coordinating drawings, because the same geometry can be misunderstood if the projection convention is assumed incorrectly.

What this standard covers

This standard covers the related symbols for these two projection methods in building drawings. In other words, it standardizes the graphic indication of the convention rather than the building geometry itself. Consistent symbols help create a common technical language across project teams and organizations. The standard is published as equivalent to ISO 2594:1972. This catalogue record is for a withdrawn standard, which makes it historically relevant for the long-standing use of projection symbols in architectural and engineering documentation.

• Symbols for direct orthographic projection and first-angle reflected orthographic projection
• Graphic notation that supports the placement logic of building drawing views
• A consistent visual reference for reading plans and elevations within the same technical system