The actions of the power plant workers in Japan have already been described as heroic, and examples of heroism are common in such situations, said Dr. Fred Mettler, a University of New Mexico radiologist and advisor to the U.N. on radiation safety.
At one point during the Chernobyl disaster, he said, workers were conferring about how much water was in one reactor pool. No one knew the answer and their instruments couldn't tell them, he said. "An Armenian engineer slipped out and came back in 30 minutes. He said, 'There's 3 feet of water,' " Mettler said. "He did that on his own."
The engineer died soon after of acute radiation poisoning.
"Its always hard to tell what people are going to do," he said. "Workers have done remarkable things, some things you wouldn't expect."
Nuclear plant workers in the United States expressed a camaraderie with their Japanese counterparts, even as they puzzled over the response to the catastrophe. "I have a lot of empathy for the Japanese people, for those workers," said Charlie Arnone, 51, general manager of plant operations at the Waterford 3 facility on the Mississippi River in Killona, La. "They're clearly very dedicated folks."
Arnone, who has worked with nuclear energy since 1977, said he and other workers train according to federal Severe Accident Mitigation Guidelines, scenarios specific to each plant. They review what could happen if, for instance, they can't maintain the water level in a spent fuel pool.
"We might hook up things, basically fire nozzles that automatically spray. Then if that doesn't work, you can open up and try air cooling," Arnone said. "We just have different guidelines and tools. My understanding is the Japanese don't have that. We have all this equipment staged. We have a generator already set up, and we can pull water out of the river if we have to, to keep the core cool, the spent fuel cool."
Experts are focusing their concern on nuclear workers because the general population's exposure to radiation around the Fukushima Daiichi plant has so far been minimal.
The government quickly evacuated a 12-mile zone around the plant. Readings of radiation outside that area have remained low.
The utility that operates the plant, Tokyo Electric Power Co., has released gases laden with radioactive substances in small bursts to prevent the buildup of pressure inside the containment buildings. For now, the winds have cooperated in blowing much of the material out to the Pacific Ocean, where scientists say it settles in the water and is diluted into concentrations that pose little danger.
Even in Chernobyl, nobody in the general population suffered radiation sickness. The U.N. says that 6,500 cases of thyroid cancer can be attributed to the disaster, but because the cases were closely monitored and treated, only a few were fatal.
Those occurred mainly because people were not warned to stop drinking milk — the main way that dangerous quantities of radioactive iodine enter the body. The isotopes land on the grass, which is then eaten by cows, turning their milk radioactive.
"All they had to say was 'don't drink the milk,' " Boice said.
"In Japan, radioactive iodines are not going to be that big a deal," he said. "They won't let the milk into the food supply."
Photos: Crisis continues in Japan
Times staff writers Molly Hennessy-Fiske, Shari Roan and W.J. Hennigan contributed to this report.