Why is Coal constently sprayed with water???

Question

and there are huge machines called dredgers which operate in coal mines 24 hours a day 7 days a week. How many tons of coal can a modern day dredger scoop out of the ground in 1 hour??

Answer 1

Because coal dust is extremely explosive.

Mining causes a tremendous amount of dust to collect in the air if it is not wetted down.

A mini dredge in a slurry settling pond can pull up to about 32 tons an hour.

I'm not sure about a full-size one, though.