Equipment failure probably caused a fatal laboratory explosion involving cold-fusion research, fire investigators said Friday.
The blast at the private SRI International lab that killed one researcher - who was once associated with much-debated cold-fusion tests in Utah - and injured three others occurred after an automatic pressure-release valve failed on a sealed canister, officials said."One of the experimenters tried to open it manually to release the pressure valve, and that's when it blew up," said Menlo Park Fire Capt. Jim Lichtenstein. "We're pretty sure that's the cause of the explosion now."
But Lichtenstein and SRI spokesman Dennis Maxwell said the explosion could have had other causes, including a chemical reaction. The institute and county and state authorities are still investigating.
"Until we figure out exactly what happened, we're stopping work on the (cold-fusion) project," Maxwell added.
Andrew Riley, 33, of Woodside, died in Thursday's explosion, which fire and laboratory officials said didn't release any harmful chemicals or radiation.
In 1989-90, Riley was project manager of the engineering group at the University of Utah's now-defunct National Cold Fusion Institute, where two scientists claimed to be the first to produce cold fusion.
At SRI, Riley and Steven Crouch-Baker, who received minor wounds in the blast, were contract scientists with Electric Power Research Institute of Palo Alto, which funds most of the cold-fusion research in the United States.
Stuart Smedley, 48, and Michael McKubre, 43, were treated for face and arm injuries and released from Stanford University hospital on Thursday. They worked for SRI on the $2 million project, said EPRI spokeswoman Barbara Klein.
SRI and EPRI officials wouldn't give details of the experiment that went awry, and they refused to let Smedley, McKubre and Crouch-Baker speak publicly. The scientists were called back to the lab Friday to help with the investigation.
The thermos-sized canister that exploded contained deuterium oxide, known as "heavy water," which can be slightly radioactive, and a metal electrode that was likely palladium, SRI said.
SRI said the researchers weren't actually trying to produce energy with their experiment.
Fusion is the force that powers the stars and hydrogen bombs through merging atoms, rather than splitting them as in fission. Scientists have been searching for ways to harness it at room temperature - "cold" fusion - as a cheap, safe and abundant source of energy.
Electrochemists B. Stanley Pons and Martin Fleischmann, who were working at the University of Utah, announced in 1989 they had achieved such a cold-fusion nuclear reaction in a beaker at room temperature. Critics, including many who couldn't duplicate the experiment, have remained unconvinced, but research continues at at least 100 laboratories. Some scientists have reported occasional small explosions from their experiments.