This is 99% invisible.

I'm Roman Mars.

When designing a commercial structure,

the architect must make the hallways wide enough for a wheelchair.

The materials must be compatible with its surrounding climate,

the beams must be able to support the building and withstand the wind.

The building should be dynamic, interesting, comfortable,

and ready to be completely abandoned if it burns.

There are a number of considerations for how a building should respond to emergency.

Horns versus strobes versus speakers.

The pulsating frequency of the light, the intensity of the light.

Smoke dampening, it goes on and on.

There's the sprinklers, the panic bars.

You know, the spring-loaded horizontal bar that you push to unlock emergency exit.

The smoke detectors, what kinds you use and the distances between them.

You know, a lot of people hardly even look up and see these things

and they just need to be there when an emergency happens.

Now, Adam Wining and Daniel Scoville are architects.

We work with them at Arxon, in beautiful downtown Oakland, California.

Most of the time, when they're working on fire safety,

they'll consult experts about where to place what kinds of architectural emergency devices.

But there's one safety device that they must design right into the building from the get-go.

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