Recent volcanic activity on the southern end of Hawaii's Big Island has destroyed hundreds of homes and resulted in the evacuation of many residents. As Kilauea continues to erupt, much of Hawaii Volcanoes National Park remains closed. It's one of the most popular destinations in the state.

The eruptions haven't stopped people from trying to see the action up-close, but when lava oozed into the ocean and caused an explosion that sent molten rock onto the roof of a tourist boat filled with sightseers, visitors started asking if it was really safe to travel near the volcano or even spend time on the Big Island. Was this frightening event a "freak" occurrence that got overblown by the media or a sign that it's no longer safe to get too close to the famous volcano?

Unpredictable activity

The tourist boat blast injured 23 people, but didn't cause any fatalities. Most of the injured suffered minor burns and abrasions.

Kilauea has been erupting for decades, so it's always closely monitored, and most people visit this part of Hawaii without incident. One of the main dangers, as the unfortunate boat passengers found out, is not a major eruption, which scientists can likely foresee by looking for changes in seismic data, but smaller explosions, which are usually caused by hot lava coming into contact with cool ocean water. This meeting of hot and cool causes steam pressure buildup that eventually leads to an explosion. Unlike a major eruption, these relatively small events are impossible to predict.

Kilauea is one of the world's most active volcanoes, so increases in activity and changes in lava flows are common. Major eruptions are quite rare, however. A major eruption occurred between 1,000 and 1,600 years ago. Another smaller, but still significant, event took place during the Middle Ages.

What about other dangers?

aerial of lava flow in Hawaii Some of the more worrisome aspects of volcanic activity are the ones you can't see. Here, steam plumes rise as lava enters the Pacific Ocean after flowing to the water from a volcanic fissure in May. (Photo: Mario Tama/Getty Images)

You'd think the biggest danger from volcanoes would come from lava. (Big Island residents who lost their homes to molten rock would certainly argue that lava is the worst aspect of volcanic activity.) Likewise, unpredictable steam-pressure explosions are frightening. However, volcanic gases pose a different kind of threat. These fumes spread to different areas depending on wind direction. If wind speed increase, the gas can move or change directions quickly. As a result, Hawaii Volcanoes National Park keeps air monitoring information up to date for people with respiratory conditions. The NPS suggests motorists close windows and run their air conditioner on recycled air mode if they encounter such volcanic fumes.

Laze, a mixture of steam haze and lava particles, is especially dangerous because it contains hydrochloric acid. Laze mostly occurs offshore. It can move quickly during periods of high wind, but it's visible and therefore avoidable.

Another volcanic gas, sulfur dioxide, is dangerous if inhaled and can cause acid rain. Recent instances of acid rain falling near Kilauea point to one of the most misunderstood aspects of volcanic activity. Despite the spectacular nature of lava and toxic gases, Kilauea impacts a relatively small portion of the island. Officials say there is little to no danger outside of the Puna region.

Limited danger

Hawaii Big Island Kilauea volcano floating lava into ocean rainbow The majority of the Big Island is safe — and open for business. (Photo: LUC KOHNEN/Shutterstock)

Some would-be visitors don't understand the relatively limited scope of the volcanic activity. In fact, the biggest danger for Big Island residents might not be the volcano itself, but the economic impact caused by tourists staying away, according to the New York Times. Kilauea is one of the state's biggest attractions and a major draw for the Big Island, which doesn't have the same kind of resort scene is Oahu. Indeed, the National Park Service estimates that the local economy (hotels, restaurants, tour operators) could lose more than $150 million because of the closure of Hawaii Volcanoes National Park alone. Roughly 30 percent of the island's residents work in the tourism industry.

The fear throughout the state is that people will cancel trips to Hawaii altogether because they don't understand that the eruptions that dominates the news only affects a portion of the southern end of the Big Island. Kilauea doesn't affect other areas on the island or any of the other islands. Kona, the main tourist area on Big Island, is 100 miles from Kilauea. Honolulu, on Oahu, is 200 miles away, and the islands of Kauai and Maui are even further from the volcano.

You can see the data for yourself

For those who are especially concerned about air quality, perhaps the most legitimate worry for visitors, Hawaii's Department of Health publishes data about sulfur dioxide content in the air, and the Environmental Protection Agency (EPA) publishes measurements of both SO2 and hydrogen sulfide near Kilauea. People who are especially concerned about air quality can find EPA data for the entire state.

The dangers posed by Kilauea's recent activity are limited to a portion of the Big Island. Though the tourist boat incident shows that it's possible to get too close, the most dangerous areas are already closed. Visitors to other parts of the Big Island and other islands in the state have no real cause for concern.