Sometimes when I look out at a busy parking area I see a herd — a moving multitude of four-wheeled wildlife — penned into a corral. Let something spook a member of that herd and there’s no telling what will happen.

At those moments, the fence around that corral better hold. The ‘fence’ might be a wall, a guardrail, or a line of bollards.

On August 4, 2012, a driver got honked at — twice — while trying to back out of a space in a multi-level parking structure in San Diego. Flustered, he confused his gas pedal for his brake, drove into a guardrail and went over the side.

That fence didn’t hold. As a police officer said to a 10News reporter at the scene when describing the guardrail that failed to stop the vehicle: “It…wouldn’t take a lot to go straight through that.”

Why did that guardrail have all the stopping power of toothpicks? I asked veteran consultant Jerry Marcus, owner of The Parking Advisory Group LLC in The Woodlands, Tex., to speculate.

“One possible explanation for this failure is poor maintenance of the facility’s barrier systems connections,” said Jerry. “Most likely, these connections were designed to code standards. Unfortunately, in many cases the every day wear and tear in a parking structure goes undetected. Patrons bump walls, connections deteriorate in the open air, and operators don’t take enough care to wash down corrosive ice melting chemicals frequently. An annual schedule of inspections will go a long way to keeping those ‘cows’ home.”

Coincidentally, ASTM International is developing a proposed new standard for testing low speed vehicle barriers, which is important news for safety-conscious designers and engineers.

What experiences have you had with parking area barriers? And how have standards and maintenance practices helped you keep your customers safe? All comments welcomed.