Prevent silica exposure in the workplace
The following advice for minimizing silica exposure comes from the federal Occupational Safety and Health Administration:
• Avoid silica-containing materials whenever possible.
Some abrasives used in sandblasting contain high levels of silica, for instance, while others do not. Try to use automatic blast cleaning machines or cabinets that allow operation of the machines from outside, using gloved armholes.
• Remove dust with a water hose, wet sweeping, or vacuum with a high-efficiency particulate filter.
Do not use compressed air or dry sweeping. Those methods only stir up the silica dust more and increase the exposure of workers, especially those doing the cleanup.
Encourage workers to follow good housekeeping practices. The buildup of dust on surfaces is a sign that silica dust is not being removed efficiently during work operations, but housekeeping practices should not make the situation worse by stirring the dust up into the air again.
• Install the appropriate engineering controls.
The appropriate control will depend on the exact circumstances of a work site, but examples include exhaust ventilation and dust collection systems, water sprays, wet drilling, enclosed cabs, and drill platform skirts.
• Encourage workers to report malfunctioning equipment.
Engineering controls such as filters can greatly reduce silica dust levels, but they must be kept in working order. Filters can clog easily, and the extreme abrasiveness of silica dust can damage almost any engineering control over time.
• Educate workers about the importance of particulate respirators.
Any respirator program requires extensive fitting, testing, and education of those using the protection, but it is particularly important to remind workers that silica dust is not just dust. Make sure the workers understand the respirator is intended to prevent a serious disease, not merely to reduce discomfort from dust. Discourage workers from wearing mustaches or beards if they must use a respirator because facial hair usually prevents a good seal on the mask.
• For sandblasting, use type CE positive pressure abrasive blasting respirators.
• Make air sampling reports available to workers.
Providing information serves several purposes. It can show the employer is concerned and taking the proper steps, and it can illustrate that silica exposure is not just a theoretical risk. Particularly if the silica levels are high, the air sampling reports can encourage workers to comply with safety precautions.
• Require workers to change into disposable or washable work clothes at the worksite when exposed to high levels of silica dust.
The dirty clothes should be removed before leaving the area of high silica exposure. If possible, have workers shower before leaving the work site.
• Prohibit eating, drinking, or using tobacco in areas of high silica exposure.
Also encourage workers to wash both their hands and faces before eating or drinking after working around silica dust.
• Post warning signs to identify work areas where respirable silica is present.
• Provide regular medical examinations to all workers who might be exposed to silica dust.
Have the X-rays read by a specialist in dust diseases.