Mount Pelee is curently dormant. There were major effects from the 1902 explosion. Over 30,000 people were killed and they had to change the capital. The pyroclastic flows heavely damaged the former capital of Saint-Pierre. The crops  the local residents were growing were severly damaged.

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Only 2 people survived the explosion that were in the direct path of the volcano, one alive because he was in a poorly ventilated, dungeon-like jail cell, and the other, living on the edge of the city, escaped with severe burns. 

Sesmic activity monitored by seismological stations located near the volcano says when and if the volcano will erupt again. If there is a lot of activity it is likely the volcano will erupt soon. But they have not detected anything for years. Deformations near the peak due to magma welling up also indicate if the volcano is going to erupt anytime soon. People check for deformations by mesuring the variation of the slope, variations of altitude, variations of distances between  fixed points on the volcano, and satellite recognitions. Last but not least the people who monitor Mount Pelee use a hydrogeochemical analysis which basically means they check for gases and temperature increase at the summit.
Mount Pelee isn't very likely to erupt but after the 1902 eruption it is considered the third deadliest volcano on earth. Mount Pelee is monitered by the Mount Pelee Volcano Observatory. Mount Pelee doesn't show any threat to the people of Martinique but if it were to explode over 20,000 people would probably be killed. One way to improve the safety of the people of Martinique from Mount Pelee is to have an evacuation route and drills.