What kills people more smoke or lava in a volcano?

Answer 1

Volcanoes technically don't produce smoke. They release ash and gasses, but not smoke. On another quick note, lava flows and large ash clouds are usually produced by different types of eruption.

Ash, overall, is more dangerous. Lava flows are usually slow-moving, giving people time to evacuate, though there are exceptions. Ash spreads much more quickly and much farther. Ashfall can weigh down on roofs, causing them to collapse, as it is actually quite dense. The ash can also damage the lungs and eyes. The most dangerous event, though, is a pyroclastic flow. These are avalanche-like flows of superheated ash, rock, and gas that race down a volcano's slopes during an explosive eruption. They often move at speeds of over 100 mph and are unsurvivable.

Answer 2

Smoke from volcanic eruptions is more likely to kill people than lava itself. The heat, ash, and gases released during an eruption can cause respiratory problems, severe burns, and other health issues. Lava moves slowly enough that people typically have time to evacuate the area before it reaches them.