Hawaii volcano tour boats required to stay farther back after lava bomb injuries

Boat operators will continue to take tourists to see lava erupting from the Kilauea volcano on Hawaii's Big Island, a day after a "lava bomb" exploded, injuring 23 people.

However, they won't be able to get as close to the lava as they used to, the U.S. Coast Guard said.

Monday, molten rock running into the ocean exploded and threw chunks of lava onto a Lava Ocean Tours boat, smashing a basketball-size hole through the boat's roof and raining smaller rocks onto the deck. Most of the injuries were burns or scrapes caused when the hot rocks fell onto the boat and its passengers.

The most seriously injured person was a woman in her 20s, who was transported to Honolulu in serious condition with a broken thigh bone.

After the accident, the U.S. Coast Guard said boats will need to remain about 1,000 feet from where the lava meets the ocean. This is a change from the 165-foot rule that had been in effect for some specially permitted tour boat operators.

Officials warned of the danger of getting close to lava entering the ocean, saying the interaction can create clouds of acid and fine glass. Despite the hazards, several companies operate such tours.

"Tour vessels are known to operate in the area going back at least 20 years," the Coast Guard said on its Facebook page.

The boat hit Monday was about 750 feet away from the explosion.

Until Monday, Kilauea's latest activity had caused relatively few direct human injuries, the Honolulu Advertiser said. One man injured his left ankle when a lava bomb hit him May 19 as he was standing on his porch.

U.S. Geological Survey volcanologist Wendy Stovall said lava bombs occur when water interacts with lava. The water flashes to steam, which causes the lava to explode into fragments, she said.

The molten rock comes from the Kilauea volcano, which has been erupting for the past 35 years. On May 3, its eruption entered a new phase when it began spurting lava through newly formed fissures in a residential neighborhood. It has destroyed more than 700 homes since then.

Contributing: The Associated Press

WFTV