Respirators: Because What You Can''t See ... Precast concrete
Nov 07, 2012· Respirators: Because What You Can''t See Can Hurt You. ... In the real world, using a respirator in a precast concrete plant can sometimes be viewed as a nuisance. Either it''s too hot to wear, it''s difficult to talk through or it just gets in the way. ... due to concrete cutting, grinding, coring, stoning, cement mixing and sweeping, or ...