A tourist accommodation business near Mt Ruapehu says it is not worried that the mountain's chance of erupting has increased.
GNS Science says tests have revealed a build-up of pressure underneath the crater lake because heat is being blocked from getting to the top. It says if that pressure is suddenly released, it could lead to an eruption.
The Department of Conservation has recommended that people stay clear of a 2km radius around the volcano's summit.
However, the director of the Ruapehu Country Lodge says she isn't worried about the volcano's spurts of activity, as they happen all the time.
Vivienne Pitman says the area is a world famous tourist attraction due to its unpredictable volcanic activity.