Sphere

by Michael Crichton

we’re in a very dangerous environment. Barnes didn’t bother to give us all the gory details. You know why the Navy has that rule about pulling people out within seventy-two hours? Because after seventy-two hours, you increase your risk of something called ‘aseptic bone necrosis.’ Nobody knows why, but the pressurized environment causes bone destruction in the leg and hip. And you know why this habitat constantly adjusts as we walk through it? It’s not because that’s slick and hightech. It’s because the helium atmosphere makes body-heat control very volatile. You can quickly become overheated, and just as quickly overchilled. Fatally so. It can happen so fast you don’t realize it until it’s too late and you drop dead. And ‘high pressure nervous syndrome’—that turns out to be sudden convulsions, paralysis, and death if the carbon-dioxide content of the atmosphere drops too low. That’s what the badges are for, to make sure we have enough CO2 in the air. That’s the only reason we have the badges. Nice, huh?”