c41ba6f4_Bulusan_Volcano_Alert_Signals__ALERT_LEVEL
[CRITERIA] Intensifying unrest characterized by earthquake swarms and volcanic tremor, many perceptible. Frequent strong ash explosions. Sustained increase, or sudden drop, of SO2 emission. Increasing rates of ground deformation and swelling of the edifice. Lava dome growth and/or lava flow increases, with increased frequency and volume of rockfall. Magmatic processes or effusive eruption underway, which can progress into highly hazardous eruption. Danger Zone may be extended up to nine (9) kilometers or more from the active crater. [ALERT LEVEL] 
4 Hazardous Eruption Imminent
Bulusan Volcano Alert Signals
ALERT LEVEL