In brickwork detailing for buildings, a bullnose brick is a special unit with a rounded arris used at exposed edges. Identify where a bullnose brick is generally not used in standard practice.

Introduction / Context:
Bullnose bricks have one or more rounded edges to improve safety, aesthetics, and durability at exposed corners. The question tests whether you can distinguish appropriate applications of bullnose units from locations that require structurally shaped bricks instead of merely rounded arrises.

Given Data / Assumptions:

• Bullnose = rounded arris; used for finishing edges.
• Arches require voussoirs with wedge geometry to carry compressive thrust.
• Decorative use is acceptable where loads are not relying on wedge action.

Concept / Approach:

Bullnose bricks are perfect where the goal is to eliminate sharp edges, resist chipping, and add a finished look (corners, skirting, steps, sills, pillar edges). However, arches work by compressive thrust through wedge-shaped voussoirs. Using a bullnose (rounded) profile does not supply the necessary wedge geometry or bearing surfaces for arch mechanics and is not standard practice for arch rings or abutment seats.

Step-by-Step Solution:

Verification / Alternative check:

Standard brickwork details reference special voussoir bricks or cut bricks for arches, not bullnose shapes for the load path.

Why Other Options Are Wrong:

Rounding corners, pillar edges, decorative edges, steps/sills: all are usual and practical uses for bullnose bricks to soften impact-prone arrises.

Common Pitfalls:

Assuming any aesthetically pleasing shape is suitable structurally in an arch; overlooking the need for wedge geometry and proper bearing.

Final Answer:

Arches (voussoirs and skewbacks)