Noise of pneumatic rock

Are pneumatic rock drills better than electric hammer drills?

The electric hammer drill was competitive with the pneumatic rock drill in terms of productivity but generated substantially less vibration, noise, and respirable silica dust exposure. Contractors who do structural upgrades to of bridges, roads, airport runways and buildings tend to use pneumatic rock drills for dowel and rod work.

Why does pneumatic rock drill produce more quartz per dust weight?

It is not known why the pneumatic rock drill generates higher levels of quartz per dust weight than the electric rotary drill. It may be that the mechanism of bit impact with the concrete with the pneumatic drill releases more respirable particles with silica than the impact mechanism with the electric drill.

How much does a pneumatic rock drill weigh?

The pneumatic rock drill (American Pneumatic Tool, Model APT-115; 8.6 kg; 48 Hz percussion frequency) is toward the low end of the weight range of rock drills. For each study, the drills were fitted with new 19 mm diameter 2-carbide tipped bits of similar mass (Hilti TE-Y for the electric drill and Crowder WB77-750-14 for the pneumatic tool).

What is a pneumatic rock drill?

Pneumatic rock drills have historically been considered as the most robust and productive tool for cutting large holes by structural contractors, stone workers, and rock miners.

What causes high dust levels in a rock drill?

The higher dust levels are due to the clearing mechanism of the pneumatic rock drill; high-pressure air is forced down the center of the rock drill bit and rapidly ejects the dust from the hole into the worker's breathing zone.

What are the limitations of noise sampling?

Another limitation for the noise sampling is the collection inside a test room with the microphone about 1 m from a wall. However, this condition is not that dissimilar to drilling inside buildings or tunnels. 5. Conclusions and recommendations