Hand-held Grinders with Wet Dust Suppression

A hand-held grinder with wet dust suppression delivers water to the surface to reduce airborne contaminants while smoothing masonry surfaces.


Risks Addressed:

Grinding concrete, stone and masonry materials containing crystalline silica is a high dust activity that in the absence of controls would place workers at risk of lung disease, cancer, chronic obstructive pulmonary disease (COPD), lung scarring and silicosis with prolonged exposure. Silicosis is an incurable, sometimes fatal disease. Such disease is well documented in the Vermont granite quarries and stone cutting sheds, and in construction operations. The NIOSH-recommended exposure limit (REL) is 0.05 mg/m3 as a time-weighted average concentration for up to a 10-hour workday during a 40-hour workweek.  OSHA has a new construction permissible exposure limit (PEL) for respirable crystalline silica of 0.05 mg/m3 as an 8-hour time weighted average (TWA).

Another less understood, but emerging hazard is engineered nanomaterials. Incredibly small particles are being added to a broad range of construction products to improve performance, but animal toxicity tests indicate a need for closer scrutiny.  There is no evidence yet that engineered nanomaterials have caused harm in exposed workers. However, it is most important that exposures be limited and that precautionary approaches be used to reduce exposure and protect construction workers from the potential hazards of engineered nanomaterials. Nano-size ultrafine titanium dioxide, which can be present in nano-enabled masonry products, has been found to cause inflammation of the lungs and lung cancer in lab animals. The National Institute for Occupational Safety and Health (NIOSH) has determined that ultrafine titanium dioxide should be considered a potential occupational carcinogen. Other engineered nanomaterials that may be present in products used in masonry work could also potentially cause harm when inhaled by construction workers. Cutting nano-enabled concrete roofing tiles without engineering controls can generate excessive amounts of airborne dust that if inhaled by workers could increase the risk of developing respiratory disease (West GH, et al. 2016). It is likely that grinding nano-enabled masonry products will generate high levels of airborne dust and possibly engineered nanomaterials in the absence of any control measures designed to reduce exposures.

OSHA has no specific regulation or Permissible Exposure Limit (PEL) for any engineered nanomaterial. However, NIOSH has a recommended exposure limit (REL) for ultrafine titanium dioxide of 0.3 mg/m3 as a time-weighted average (TWA) concentration for up to 10 hours/day during a 40-hour week. The intent of the REL is to lower the risk to workers of the potential for developing lung cancer.


How Risks are Reduced:

Water is delivered to the grinding disc where it combines with particles created by grinding of stone, concrete and masonry materials and the now larger particles settle. Silica in the concrete and masonry materials is only hazardous if it is inhaled and is not hazardous for skin contact.  As long as the dust does not become airborne, the hazard is reduced. The extent to which these tools are effective in meeting recommended exposure limits has not been evaluated.  For nano-enabled masonry products, wet dust suppression is also likely to be effective in reducing concentrations of airborne engineered nanomaterials in a worker’s breathing zone.

Availability

Intertool: DS 175 7-inch and Intertool DS3011 12-inch planetary polisher with wet dust suppression
To obtain information, visit DS 175 7-inch and DS 3011 12-inch or contact 1-800-926-9244 mm@leitchco.com

Flex North America, Inc.: LW 1509 wet grinder
To obtain information, visit LW 1509 or contact 1-877-331-6103 http://flexnorthamerica.com/contact.php

MK Diamond Products, Inc. MK-1503-Air pneumatic polisher and MK-1503SS polisher with wet dust suppression
To obtain information, visit MK-1503 or contact 1-800-421-5830 customerservice@mkdiamond.com