Crash barrier

A crash barrier is a corrugated steel beam bolted to a line of posts, designed to deform on impact so a vehicle is held in the traffic space instead of ending up in whatever is behind it. Almost everyone calls it Armco, after the company that first made the profile.

It is a consumable safety product rather than a permanent structure. The barrier does its job by bending, so a section that has taken a real hit has already spent part of what it had and should be replaced rather than admired.

What a run is made of

• Beams at 3504mm overall, 3200mm effective once they overlap at the post.
• Posts in two profiles: the 100 x 50mm Z post for car parks and yards, the heavier H post where the barrier protects racking, plant, columns or services.
• Corner sections, internal and external, for changes of direction.
• Terminals: a UK-style fish tail end, a pedestrian end where the run finishes beside a walkway, or a yellow end cap as a retrofit.
• Two M16 bolts — the 50mm post bolt fixes beam to post, the 35mm lap bolt joins beam to beam.

Dig in or bolt down

Both post profiles come as dig-in posts for concreting into the ground, and base plated at 560mm and 760mm overall for bolting to an existing slab. Dig in is the stronger detail; bolt down exists for finished floors and hardstanding, and puts the weak point into the concrete.