CAREX Canada* estimates that approximately 429,000 workers in Canada are occupationally exposed to silica.
Once released into the air as dust, respirable silica can lead to serious illnesses such as silicosis and lung cancer.
Silica is a hazard in many industries. Workers in construction are particularly susceptible to silica exposure.
Cement
Bricks
Stones, sand, or gravel
Glass
Tiles and ceramics
Engineered stone and granite
Silica can become respirable when any of these products are handled, manipulated, or processed in some way that generates dust.
Respirable silica dust contains small particles which can be inhaled and travel deep into the worker’s lungs. Here, it’s crystalline structure allows it to insert into the lung tissue. Scar tissue builds up around the silica particles and leads to a decrease in lung function which can result in lung diseases such as silicosis and lung cancer.
Available to all New Brunswick employers, the Silica Control Tool allows to anticipate exposures for a specific task, select appropriate controls, and establish an Exposure Control Plan detailing personal protective equipment required – all without the need for elaborate and costly sampling.
Simple, easy to use and data driven, the Silica Control Tool provides workplaces with a convenient way to reduce the serious risks posed by Respirable Silica.
How to use the Silica Control Tool:
You will need your company’s WorkSafeNB employer number and your legal company name as registered with WorkSafeNB.
Often companies registered with WorkSafeNB have both a legal and an ‘operating’ name. You will need the registered legal name, which may be different from the more commonly used operating name. You can find your legal company name on any documents sent to you by WorkSafeNB.
If you are registered with WorkSafeNB, and don’t know your employer number, ask your finance or HR department. Make sure your WorkSafeNB employer number is entered exactly as shown on official WorkSafeNB documents.
NB General Regulation 91-191 requires employers to arrange for air testing to determine the level of concentration of an air contaminant when the concentration of the air contaminant may reach 50% of its Occupational Exposure Limit (OEL). A work process generating silica dust in the workplace would trigger this clause. Therefore, the employer is required to determine the level of silica exposure either by conducting air sampling or by use of the Silica Control Tool, and to implement reasonable controls based on the results. WorkSafeNB accepts both methods.
When silica-containing products are manipulated in some way to generate dust, fine crystalline particles are released into the air. Respirable indicates that the silica particles are small enough (less than 10 µm) to reach deep into the alveolar region in the lungs.
When silica particles are inhaled, they can deposit into the alveolar region of the lungs, where scar tissue forms around them leading to significant damage to lung tissue. The resulting, often fatal, disease is called silicosis.
Chronic silicosis is most common and progresses slowly after years of exposure. Silicosis can also occur acutely after exposure to high concentrations. Symptoms can include shortness of breath, cough, fever, weakness, and eventually lead to respiratory failure.
Silicosis is progressive and irreversible. Even if the exposure ceases, the disease continues to progress.
More information on silicosis at CCOHS: Silicosis
Exposure to respirable crystalline silica puts workers at risk for developing other serious diseases including:
Workers who manipulate silica containing materials, such as sand, rock, gravel, concrete, brick, stone, mortar, granite, glass, or ceramics. Dust generating activities such as moving, grinding, cutting, sandblasting, drilling, crushing, mining, or demolition create a risk to the worker. Working with engineered stone products can be particularly hazardous due to the high silica content of the material.
Development of silicosis can be influenced by:
Source: CCOHS: Silicosis
Exposure to respirable silica can be prevented with multiple levels of control. Ideally, processes that create respirable silica would be excluded or replaced if possible. Physical barriers can be very effective as well as wetting of materials, local exhaust ventilation, dust-collecting systems, and finally personal protective equipment (PPE) such as respirators.
The Silica Control Tool can assist employers in establishing appropriate controls.
The occupational exposure limit has been established for respirable silica at 0.025 mg/m3. But what does that mean and how can you judge if the dust generated during a given work task will exceed the limit without elaborate and lengthy testing? The Silica Control Tool can help.
The Silica Control Tool will generate an Exposure Control Plan describing the anticipated exposure, chosen control options, and resulting level of respiratory protection required (if any). This plan can be used to communicate the controls and requirements to the workers performing the task, train workers and raise awareness. The Exposure Control Plan can be used by employers to demonstrate compliance to WorkSafeNB Health and Safety Officers. The Officers can use the plan to verify that they are followed as described in the plan, the selected control options are in place and effective, and the level of respiratory protection (if any) used by workers is adequate.
New Brunswick’s occupational exposure limit for Silica is 0.025 mg/m3. Employers must ensure that the exposure of an employee at no time exceeds the occupational exposure limit and must implement and maintain appropriate controls for this purpose. Furthermore, employers must determine the level of exposure to respirable silica when the concentration may reach 50% of the occupational exposure limit.
The Silica Control Tool can assist employers in determining the level of exposure, and in the selection and implementation of appropriate controls.
