The Occupational Safety and Health Administration (OSHA) announced new regulations in March to improve protections for workers exposed to respirable crystalline silica dust. The agency aims to further reduce lung cancer, silicosis, chronic obstructive pulmonary disease, kidney disease and other illnesses caused by the inhalation of crystalline silica.
OSHA regulations previously allowed airborne levels of 250 micrograms per cubic meter (μg/m3). The new regulation limits exposure to 50 μg/m3. A pending a court challenge may change the date that new regulations actually take effect, but the regulations will change nevertheless. As a result, manufacturers of products are introducing methods to control silica dust, and contractors will be gearing up to provide their workers with additional protection.
The systems approach
Shi Srinivasan, director of marketing for DeWalt, says manufacturers address dust control in three ways: moving air and dust through vacuums, improving dust filters and providing better dust shrouds for tools. Taken together, these methods form a system that can meet the new OSHA limits.
Tools depend more on vacuum cleaners that have enough airflow to collect airborne dust of all types. The role of vacuum cleaners, once just about keeping a job area clean, is changing. Phillip Bolton, DeWalt’s product manager for metal cutting and dust management, says contractors should look for vacuums with good airflow, tight connections and secure attachment systems for tool shrouds.
“Look for vacuums with dedicated power systems too,” he says. “When you turn on your power tool, the vacuum also starts. When the tool is turned off, the vacuum turns off a few seconds later, allowing time to clear dust from the lines and the tool.”
Bolton says that jobsite vacuums need HEPA filters in order to control silica dust. But better filters reduce airflow, so vacuums must have stronger airflow to effectively use them—ruling out low-cost models. HEPA filters can filter 99 percent of dust that is 0.3 microns in size, qualifying them to meet the new OSHA standard for silica dust.
Collecting dust at the tool
As concern for airborne dust increases, manufacturers are devising better methods of collecting it at the source. Most woodworking tools now have shrouds built into the tool, and grinders, saws, drills and polishing equipment used for concrete work have shroud attachments capable of collecting nearly all of the silica dust they create.
Some concrete drills feature vacuum holes that run through the center of the drill shank down to the bit, so a vacuum can transport dust away from the drilled surface as it is created—which is especially useful for drilling holes to install resin anchors.
Why we should be concerned about silica
Respirable silica can find its way into a person’s lungs and—once there—can’t be removed. Lung capacity is diminished over time and, depending on the amount of exposure, a person becomes more susceptible to lung diseases. It’s estimated that 2 million construction workers are exposed to silica dust every year.
If you must work in areas where airborne silica dust will be present, the National Institute for Occupational Safety and Health recommends using half-face particulate respirators with N95 or better filters.
Be sure to join the Lowe’s ProServices LinkedIn Group to read additional content and interact with other Construction/Trade and MRO professionals.