Falls into Nuclear Reactor and Survives

On 21 October 2025, a contractor for the Palisades Nuclear Plant in Michigan fell into a pool of water above the main reactor and survived. The previous day, the nuclear plant received a batch of fresh fuel rods, which were stored in the pool as part of their preparations to reopen the plant after the 2018 shutdown. The contractor reportedly ingested some of this water during the incident but was immediately decontaminated and has since exhibited no symptoms of radiation poisoning.

"The worker was promptly assisted from the water, evaluated, monitored, and decontaminated for removable contamination in accordance with established industry standards and safety procedures," said spokesman Nick Culp in an official statement. After the decontamination process was complete, the contractor’s exposure was 300 counts per minute. Holtec International, which owns the plant, expressed confidence that the radiation was within safe levels and was more focused on water safety compliance. The worker was later taken to the hospital as an additional precaution, where he was treated for minor injuries related to the fall. The event was reported to the Nuclear Regulatory Commission as a non-emergency and there have been no further updates from Holtec.

But how is it that someone can fall into a reactor? Well, the Palisades Power Plant is one of many plants called swimming pool reactors. The premise revolves around the main nuclear reactor core (the part containing the nuclear fuel and control rods) sitting in an open pool of water. This design solves many hurdles in fission with relative ease, as the water allows easy access to the reactor core, cools the reactor, and encourages sustained reactions at the same time. Water also happens to be extremely good at blocking radiation, counterintuitively making these reactors particularly safe. In fact, the radiation exposure just below the surface of these pools is lower than that of the ambient atmosphere, hence why this accident caused so little concern. The largest risk from open pool reactors is typically drowning, which is mitigated by life vest regulations.

Perhaps surprisingly, the specialised divers who routinely go swimming in these reactors with protective suits to execute repairs rarely experience complications. Radiation is carefully monitored for all their dives, and limits are set to ensure that they never exceed dangerous levels (typically three times the average annual exposure). 

This event highlights, if anything, just how safe nuclear reactors have become in recent years, but headlines have provoked pushback from residents. Following the accident there were a number of protests regarding nuclear and consumer safety, but the plant’s reopening has remained unimpeded. Both the Nuclear Regulatory Commission and Holtec cite the drastically lower rates of injury and fatality in nuclear reactors than in coal, oil, and offshore wind generators. As reactor science and safety become increasingly sophisticated, these rates keep falling, making nuclear one of the safest power sources worldwide.

Illustration by Alice O'sullivan