SILICA DUST THE NEW ASBESTOS?

WorkSafeBC launched an awareness campaign in September focused on enforcing jobsite specifications around the control of airborne dust and chemical contaminates including silica dust—a substance some are referring to as “the new asbestos.”

Silica is a common substance found in sand, rock, and building materials such as concrete and brick. Crystalline silica dust is released into the air each time these materials are cut, ground, or drilled, and breathing these particles can cause permanent lung damage.

Airborne silica mainly affects people working with rock, concrete, masonry, or heavy steel, but every subtrade—especially those completing hospital or other institutional projects—is cautioned to be aware and create an exposure control plan for employees.

Exposure to silica dust over as few as one to three years on a continual basis, or over a lifetime of occasional unprotected exposure can lead to silicosis, a thickening and scarring of the lung tissue.

Chronis silicosis develops after 10 or more years of exposure in relatively low doses; accelerated silicosis develops five to 10 years after initial exposure to crystalline silica at high concentrations, and acute silicosis can occur anywhere from a few weeks to four to five years after exposure to extremely high concentrations of the dust.

Symptoms include shortness of breath, severe cough, and weakness and can become progressively worse and sometimes result in death.

Under Section 5.54 (Exposure control plan) of the Occupational Health and Safety Regulation employers are required to develop an exposure control plan in any cases where employees may be exposed to airborne silica dust in excess of 50 percent of the exposure limit.

Al Johnson, regional director for WorkSafeBC says the organization has increased its focus on occupational diseases because of statistics which indicate that while there has been a decrease in the number of traumatic fatalities, fatalities due to occupational disease are increasing.

“Typically, as people are exposed to chemical substances it can take a number of years to manifest,” says Johnson. “People exposed over a lifetime are dying in their 50s to 70s, which is why we are working at preventing exposures today.”

According to the Yukon Workers’ Compensation Health and Safety Board worker exposure to crystalline silica and other air contaminants often goes unchecked because some companies lack organized respiratory protection programs or sufficient employee training.

Johnson says WorkSafeBC’s campaign is asking employers to take the issue more seriously and overcome the older culture of the industry that said safety equipment wasn’t necessary.

“Ten years ago no one wore a respirator, but today not so much,” he says. “Now a respirator is a standard piece of equipment that anyone working with these substances should use. There are also vacuum cleaners that capture concrete grinding dust and drills with build in vacuums.”

Preventative control measures can sometimes be as simple as construction managers and industrial hygienists planning ahead to eliminate or control silica dust at the source. Wetting the dust before it becomes airborne and having filtered or respiration equipment on hand are important.

Air monitoring can ensure restrictive exposure limits are not exceeded, or if they are, that workers are sufficiently protected.

For more information visit WorkSafeBC at www.worksafebc.com and search for “silica dust” under “hazardous materials.”