Putting a stop to drilling dust27. April 2018
You know the drill. The bit is mounted onto the drilling machine. Your target is marked with pencil and clearly in front of your eyes. Ready, steady, go. A feeling of satisfaction many a handyman knows too well. However, taking a deep breath after drilling is perhaps not what you should do on a construction site. Drilling inevitably creates dust – often so much that many workers might feel tempted to leave long before it settles. Whether concrete worker, mason, carpenter, fitter, insulation worker or electrician, there is one thing that unites these different trades: Drilling – and the resultant troublesome dust.
Boring dust: Be on the alert!
“Drilling dust poses a danger – both technically and healthwise,” says Dr. Christian Schlenk, a chemist at fischer. “Unfortunately, it’s considered normal on-site. And as a result, it’s being terribly underestimated.”
When using mechanical fixing systems, dust in a drill hole can significantly diminish the friction between a wall plug and the surrounding construction material: It can reduce the load-bearing capacity of plugs by up to 50 percent. With regard to chemical plugs, dust functions as a separation layer between the anchor and the mortar. “If you flour your hands before kneading cake dough, it has a similar effect,” Schlenk explains. “The flour lowers adhesion – and the dough doesn’t stick to your hands.” In addition, the desired anchorage depth may not be achieved. “Especially in the case of heavy loads, fixing systems can slip out of position – or even break away.”
Then again, if drilling dust is released into the air, for example by blowing out the drill hole with pressurized air, it presents a risk to peoples’ health. As early as the 16th century, Swedish scholar warned against the effects of dust: It would settle so dangerously in one’s throat and pharynx that “only the rapid drinking of fresh beer” could help. From today’s perspective, this piece of advice might seem questionable on construction sites. However, the health effects of the pernicious particles are undisputed.
A creeping threat
Dust is light. And dust is quiet. Yet when exposed to it on a permanent basis, it can become a subtle burden for humans. Once in the air, the tiny particles and fibers can stay there for hours. Did you know that a speck of dust just 1 micrometer (μm) in length will only descend one meter in seven hours?
Risk, however, is on the rise: All dust grains tinier than 10 μm are inhalable. Ultrafine particles smaller than 2 μm are more problematic still. They can reach a human’s deeper airways and pulmonary alveoli – and do significant harm. “The particles can become enclosed in one’s lung tissue,” Schlenk says. Depending on the amount and duration of exposure, they can lead to inflammatory responses, bronchitis and allergies. Quartziferous dust particles are even genetically harmful. Over time, they can cause silicosis (also known as grinder’s asthma) or even cancer.
The limit values for permitted dust concentrations have been tightened in recent years. However, even with conventional drilling in concrete, it is easy to exceed this limit by a factor of five. According to the German insurance association for the building industry (BG Bau), this limit could already be exceeded by pulverizing one sugar cube and distributing it into a room’s air. So what steps can be taken? Should we simply tackle the problem when and where it arises?
New tools – cleaner air!
Ventilating the workplace and using low-dust building materials offer a certain level of protection, but it is certainly not enough. Filter masks guard us from dust, but they are often impracticable and uncomfortable to wear. “Extraction drills, however, also known as hollow-core drills, offer an elegant solution,” Schlenk says. “They remove dust where it originates: right at the drill bit.” Via suction openings, the drilling dust is carried off through the hollow shaft, before safely landing in a connected vacuum cleaner.
The advantages are obvious to Schlenk: “No dust is blown into the room – a great gain in air quality.” Added to this is the improved time and cost efficiency: With hollow-core drills, work can be done more quickly. Not only do they replace the manual cleaning of a drill hole by extracting dust, they also accelerate the drill’s advance. Increasing anchorage depth reduces the installation time of bonded anchors by up to 40 percent.
Manufacturers of fixing systems first have to check whether the extraction drills are suitable for their anchors – a requirement that fischer comprehensively complies with: “We have to prove that hollow-core drills achieve a degree of cleanliness that meets our requirements as a wall plug producer,” Schlenk explains. “We do this for each of our products.” The benefit for customers? A transparent basis for the selection of a drill. And even safer plugs in the wall.
Industrial safety first
fischer is firmly committed to avoiding dust as a risk factor in construction. For Christian Schlenk, there is no way around extraction drills: On the road to dust-free construction sites, the new tools play a key role. Their use ensures the load capacity of all types of plugs. The drills help handymen to work cost efficiently – and protect their health. “We want to offer customers the best possible fixing systems,” Schlenk says. “At the same time, we see the improvement of safety at work as part of our responsibility.” Currently, the young technology is still costly. “But our goal is to contribute to a wider adoption of extraction drills.”