For those who don't know, structural engineering is quite an important but little understood part of the construction industry. When I put it in the simplest way, it's best explained that an architect designs how a structure looks and the structural engineer makes sure it stands up...or more importantly, doesn't fall down. Since the aesthetics of a structure are what you see, the architect usually gets most of the attention and the structural engineer doesn't come into the limelight until a catastrophe happens, such as the Hyatt Regency walkway collapse or the collapse of the World Trade Center.

A structural engineer can be responsible for designing something as simple as a small deck to something as large as a bridge or skyscraper. I had a moment of realization, and fear, when I was working on a 7-story building and suddenly realized that people were actually going to use this thing and trust their lives to it in the event of an earthquake. How many people are there in a 7-story office building on any typical weekday? One thousand? Two? That's a lot of people relying on a design that's made up of computer analyses, hand calculations, and educated assumptions. The truth of the matter is, though, that it really takes a lot to make a building fail in such a catastrophic way that many lives are lost. It tends to be the small things that can make the biggest difference, such as the one detail change for the Hyatt Regency walkway. Something that appeared to be a simple alternative, turned out to be a devastatingly wrong decision.

But, for the few failures that do occur, there are thousands of structures that we use everyday without a thought or worry about its structural integrity. And that's exactly how it should be.