Support design: when can wind load be neglected for process vessels and tanks?

Introduction / Context:
External loads on vessels include wind and seismic forces. Designers determine when these actions are governing, negligible, or must be combined with operating loads. This question checks the practical case where wind loading can be ignored.

Given Data / Assumptions:

• Wind acts as a lateral pressure on exposed surfaces.
• Indoor, low-height equipment is largely shielded from wind.
• “Tall” vessels present large projected areas and higher overturning moments.

Concept / Approach:
Wind loads are typically considered for outdoor equipment with substantial height or area because they create significant shear and overturning moments. If a vessel is short and located indoors, the envelope of the building shields the vessel, allowing wind to be neglected in design load combinations.

Step-by-Step Solution:

Verification / Alternative check:
Design codes and recommended practices emphasize exposure category and height. Indoor short vessels normally consider only dead load, operating load, and possibly seismic if required.

Why Other Options Are Wrong:

• Tall and full or tall but empty: tall geometry always demands wind checks.
• Outdoors but sheltered: still exposed; wind generally cannot be ignored.
• None of these: incorrect since the indoor short case exists.

Common Pitfalls:
Neglecting wind on outdoor equipment; assuming shielding without proof; forgetting that even indoor equipment might need seismic checks depending on location.

Final Answer:
When the vessel is short (less than 2 m) and installed indoors