Michelle Coombs, from the US Geological Survey, described it as a “a big event that got people’s attention but not with widespread impact”.
An ash cloud rose up to 30,000 feet above sea level following the explosion at 4:17am local time (3:17pm BST) from Halema‘uma‘u crater.
Additional ash emissions are expected as the summit area remains unsettled.
In Pahoa, schools and the post office have been closed due to elevated levels of sulfur dioxide.
Fenix Grange of the state Department of Health said 10 new air quality monitors have been installed “circling the rift areas.”
Mr Grange said, at about 6:45am (5:45pm BST), there was a reading of “condition red” at a monitor at Pahoa Fire Station.
Condition red means there is at least one part per million of sulfur dioxide in the air and that severe health effects could occur such as choking and inability to breath.
The reading at the Pahoa Fire Station was reportedly 2.7 parts per million.
Mr Grange said the best thing to do is to “get out of Dodge” in an area where sulfur dioxide levels are at condition red.
Geologists say ground deformation continues in lower Puna along the rift zone, indicating that magma continues to buildup underground.
Michelle Coombs described the events at Halema‘uma‘u as “a real dynamic situation”.
She said: “We could have additional events like this morning that punch up then die down really quickly, we could have more sustained ash coming out of Halema‘uma‘u.
“The one this morning is definitely the biggest we’ve seen so far, just in terms of energy and how high up into the atmosphere it got.”
Ash masks will be distributed in Pahala, Volcano, Na‘alehu and Kea‘au, the county said in a news release.
The highly active volcano could keep erupting for weeks and scientists have no idea when the activity will calm down.
Volcanologist Janine Krippner of Concord University in West Virginia said: “There’s so many variables. It’s complicated, like a bad Facebook relationship status.
“Something will eventually change like it has over and over and over again.”
The last time Kilauea saw a period of explosive activity was May 1924, which is 94 years ago this month.
There were 50 explosive activities recorded in a two and a half week period and ballistic blocks weighing up to 14tons were thrown from the crater, Krippner said.
Kilauea is one of the world’s most active volcanoes and has been erupting continuously since 1983.
Scientists understand the mechanics of what is causing the outburst but they have no idea why, after 35 years, Kilauea is exploding in different ways.