Visit Sunny Chernobyl: And Other Adventures in the World's Most Polluted Places

they’re tiny and will shoot off like bullets, colliding with neighboring uranium atoms and causing them to split. This will give off more heat and more neutrons, which will cause still further atoms to split, and so on, and so on, and so on. The immense heat created by this chain reaction will heat the water, which will create the steam, which will spin the turbines at terrifying speed, which will turn the generators, which will create an ungodly amount of electricity, which will be used to keep office buildings uncomfortably cold in the middle of summer.

So far, so good.

The problem with this chain reaction is that, by its very nature, it tends to run out of control. So to keep your reactor’s apocalyptic side in check, you should slide some rods made of boron or hafnium into the reactor core. (Remember to make room for them while you’re stacking the uranium.) These rods—let’s call them control rods—will be like sponges, absorbing all those lively, bullet-like neutrons. With the control rods duly inserted, you’ll get…nothing.

The trick, then, is to find the happy medium, while remaining on the correct side of the line that separates air-conditioning from catastrophe. To do this, you’ll need to pull the control rods out of the core far enough to let the chain reaction begin, but not so far that it runs out of control. Then you can heat water and spin turbines and generate electricity to your heart’s content.

But pull the control rods out slowly, okay? And for the love of God, please— please—put them back when you’re done.

With the Chernobyl Museum taken care of, I had a couple of days to kill in Kiev before my excursion to Chernobyl itself, and I spent them exploring my new neighborhood. I was living in style, sidestepping Kiev’s overpriced hotels by renting an inexpensive apartment that was nevertheless nicer than any I had ever lived in back home. The front door of my building opened onto the bustling but cozy street of Zhitomirskaya, and it was an easy walk to Saint Sophia Square. There was also a nice terrace park where the young and hip of Kiev would gather in the late afternoon to throw Frisbees, play bongo drums, and drink beer in the glow of the sunset.

It all filled me with a churning panic. I just don’t like being a clueless foreigner in a strange city where I’ve got no friends. I was also having trouble finding a portable radiation detector for my trip to the Exclusion Zone around Chernobyl. The detector would come in handy for measuring my radioactive exposure, with great precision, in units I wouldn’t understand. But Amazon didn’t deliver overnight to Kiev, and so I was out of ideas. It was time to be resourceful—I had to get someone else to figure it out.

If journalism can teach us anything, it’s that local people are a powerful tool to save us from our own fecklessness and incompetence. We call them fixers. In my case, I hired a capable young journalism school graduate called Olena. Skeptical at first, she soon realized that I was less interested in a simple rehash of the local disaster story than in exploring new touristic horizons, and she warmed to the concept. Olena set to work finding the radiation detector, calling one Chernobyl-related bureaucracy after another. To our surprise, nobody had any ideas. Even the government’s Chernobyl ministry, Chernobylinterinform, was clueless. Measuring radiation didn’t seem to be much of a priority among the citizens of Kiev. Maybe they just didn’t want to think about what lay a short way upriver.

It’s possible there is wisdom in such willful ignorance. The subject of radiation, after all, is so mysterious, and its units and measurement so confusing, that carrying around a little beeping gadget may not, in the end, leave you any better informed about your safety.

But every visitor to Chernobyl should have a working understanding of radiation and how it’s measured. So let’s review the basics. You can skip this section if you want, but you’ll miss the part where I tell you the one weird old tip for repelling gamma rays.

Radiation, as far as tourists need be concerned, comes in three flavors: alpha, beta, and gamma. One source of radiation is unstable atoms—those same atoms that are so useful in building a nuclear core. In contrast to lighter, trustier elements like iron or helium, uncomfortably obese elements like uranium and plutonium are always looking for excuses to shed bits of themselves. That is to say, they are radioactive. These unstable elements will occasionally fart out things we call alpha or beta particles or gamma rays—the latter being the nasty stuff. This process—called decay—leaves the atom a bit smaller and sometimes with a different name, as it is alchemically transformed from one radioactive element into another.

Once in a while, an atom will suffer a complete breakdown and split in half. That’s fission. After the split, particles and gamma rays spew off in all directions, and two atoms of a lighter element are left behind.

But we’ll get to that. The point is, between decay and fission and other sources, there’s radiation zipping around and through us all the time. There’s the natural decay of Earth’s atoms, and there are cosmic rays shooting down at us from outer space (you get a higher dose when you’re up in an airplane), and then there’s the X-ray your dentist gave you, and so on. You’re getting irradiated all the time. But don’t freak out yet. Although radiation can burn your skin, give you cancer, and disrupt the functioning of your very cells, it takes a lot of it.

And that’s the problem. How much counts as a lot? It’s hard even to predict how badly you’ll get sunburned on a day trip to the beach, and that’s with plain old solar radiation. In the nuclear case, your only hope of a clue is to have a radiation detector on hand.

Even with a detector, you’re likely to remain confused by the bewildering array of terms and units with which radiation and radioactive dosage are measured. There are rads and rems, sieverts and grays, roentgens, curies and becquerels, around which buzz a swarm of attending coulombs, ergs, and joules. You might want to know the disintegration rate of a radioactive material, or its potential to ionize the air around it, or the amount of energy it can impart to solid matter, or the amount of energy it actually does impart to the living tissue of hapless organisms—such as Chernobyl tourists—and on and on.

And then it all depends on how quickly you get your dose. In this, radiation is analogous to certain other poisons, such as alcohol. A single shot of bourbon every weekend for a year is hardly dangerous. But fifty shots on a single night will kill you.

Finally, it matters which part of your body gets irradiated. Limb? Count yourself lucky. Guts? Not so much.

So it’s no wonder that radiation is so mysterious and frightening, and that it features in the backstories of so many comic book monsters. It’s invisible, deadly, cosmic, extremely confusing, and rides shotgun with the nuclear apocalypse. The stuff is just spooky, and if—like me—you’re never going to have an intuitive understanding of its dosage and true risks, you might as well ease off on worrying about it so much. The purpose of the detector, then, is not to better understand the danger in your environment, but to gather up your anxiety and bundle it into a single number on a small digital readout, so you can carry your fear more efficiently.

Oh—and the tip for repelling gamma rays is that you can’t.

Olena had a plan. “Let’s go to Karavayevi Dachi,” she said. “Electronics black market.”

What Manhattan’s Chinatown is to food, Kiev’s Karavayevi Dachi is to electronics. It was early afternoon when we arrived. Metal stalls lined its alleys, roller-fronts thrown up to reveal jumbles of electronic components and devices. Men with rough, sun-cured faces sat at wooden folding tables strewn with vacuum tubes, transformers, electrical plugs, computer chips, adapters. The husks of car stereos hung in bunches, banana-like. It seemed doubtful that we would find a working radiation detector here among the tangled heaps of wires and transistors, and as we went from stall to stall, the conversations followed a pattern that always ended in “nyet.”

One man claimed to have a detector at home that he would sell us for only 150 hryvnia—about thirty bucks. The catch was that it could only detect beta radiation. Forget it, dude. Any simpleton knows that beta particles— which can be blocked by regular clothes—are nowhere near as scary or stylish as gamma rays. We walked off to another part of the market, the annoyed vendor calling after us in protest, “But beta is the best!”

Another man had been eavesdropping and now approached us. He knew of a better place to find radiation detectors, he said, just a five-minute walk up the street. He would be happy to take us there. We left Karavayevi Dachi behind and made our way up a tree-lined street of brick apartment blocks.

Our guide’s name was Volod. A middle-aged man with receding hair brushed straight back, he wore a beige coat over a striped beige shirt and beige jeans, and didn’t seem to have much more of an idea than I did of where we were going. Our five-minute walk grew to fifteen and then twenty minutes, and I became progressively less convinced that we were detector-bound.

Striking up a conversation, we soon learned that Volod had been a communications officer in the Soviet army