Construction Dust Mask

A dust mask is a flexible paper pad held over the nose and mouth by elastic or rubber straps for personal comfort against non-toxic nuisance dusts. They are not intended to provide protection from toxic airborne hazards.    

What is the difference between a dust mask and a respirator?

The most significant difference between dust masks and respirators is that dust masks aren't NIOSH-approved disposable filtering facepieces. ... 

They are ideal for non-hazardous environments and are not considered to be a personal protective device that can provide respiratory protection to the wearer.