Define the role
A visual traffic-control bollard is different from a tested impact-security system. Do not imply vehicle-impact resistance without exact current evidence.
Build Project BriefPublic Realm & Development · Streetscape answer
Bollards can guide movement, protect edges or perform specialist security roles. Those functions are not interchangeable.

A visual traffic-control bollard is different from a tested impact-security system. Do not imply vehicle-impact resistance without exact current evidence.
Final spacing, foundations, accessible movement and emergency/service access belong in the local site design.
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