Crystalline silica dust is created by cutting, grinding, drilling, and blasting masonry, stone, and concrete. Inhalation of silica dust causes silicosis, an irreversible lung disease that reduces lung function and increases susceptibility to tuberculosis and lung cancer. The OSHA permissible exposure limit is 50 micrograms per cubic meter of air over an 8-hour shift. Engineering controls including water spray systems and local exhaust ventilation are the primary control methods. Water spray during concrete cutting and grinding suppresses dust at the source. The combination of water and silica forms slurry reducing airborne dust. Wet sweeping instead of dry sweeping prevents resuspension of dust. Enclosures around grinding or cutting operations contain dust and allow local ventilation. Ventilation systems draw dust through HEPA (high-efficiency particulate air) filters. HEPA filters trap silica particles; cartridge replacement prevents accumulation. Mobile grinding stations with integral dust collection reduce exposure for multiple workers. Respirator use is a secondary control when engineering controls are inadequate. Respirators must be NIOSH-approved and properly fitted. Half-mask respirators with P100 cartridges are typical for construction dust. Full-face respirators provide better seal and visibility. Supplied air respirators eliminate dependence on cartridge replacement. Workers must be trained on proper donning and seal checking. Medical surveillance including annual chest X-rays and lung function tests documents health effects. Workers with lung disease must be informed and provided additional protective equipment. Awareness of silica hazards is essential; many workers do not recognize the danger.