4 ms·
The ironic thing is that this illness is due to non-coal dust (silicates) in the air which are much finer than coal dust. And because they are non-coal dust, th
by test6554 8y ago
The ironic thing is that this illness is due to non-coal dust (silicates) in the air which are much finer than coal dust. And because they are non-coal dust, they escaped regulation for a long time.