Cutting pavers, bricks, blocks, and other masonry materials generates a large amount of dust which may contain high levels of crystalline silica and create a hazard for everyone in the vicinity.  Wet dust suppression is a control option for dust generated while cutting masonry materials.  A stationary masonry saw with a water system controls the dust at the source. A pump is used to deliver fresh or recycled water to the saw blade where it combines with particles and reduces airborne dust levels. Some models include a feature to capture and recycle the water.  In some cases a hose is connected to a separate water source that provides a continous flow of fresh water and eliminates the need for pumps and filters.  Both electric and gas powered versions are available.

The following are examples of saws with wet dust suppression available commercially:

EDCO, Inc. electric (Model GMS-10-1.5B) and gasoline (Models GMS-10-4H and GMS-10-5.5H) hardscape masonry saws with 10-inch blade and water connection

EDCO, Inc. electric (Model HSS-14-1.5B) and gasoline (Models HSS-14-5.5H and HSS-14-6.5H) hardscape masonry saws with 14-inch blade and water connection

EDCO, Inc. electric (Model BB-14-1.5B) and gasoline (Models BB-14-5.5H, BB-14-6.5H and BB-14-9H) masonry saws with 14-inch blade and water connection

EDCO electric (Models MS-20-5B and MS-20-7.5H) gasoline (GMS-20-9H and GMS-20-11H) masonry saws with 20-inch blade and water connection

MK Diamond Products, Inc. BX-4 stationary masonry saw with water misting dust control and 14-inch blade

MK Diamond Products, Inc. MK-2000 series stationary masonry saws with water misting dust control and 14-inch blade

MK Diamond Products, Inc. MK-5000 series stationary masonry saws with water misting dust control

MK Diamond Products, Inc. MK-5010 Super-Matic series stationary masonry saws with water misting dust control

Husqvarna Portasaw MS 355 series stationary masonry saws with water spray dust control

EDCO, Inc. electric (Model GMS-10-1.5B) and gasoline (Models GMS-10-4H and GMS-10-5.5H) hardscape masonry saws with 10-inch blade and water connection

• Used for cutting interlocking pavers, brick and stone or brick veneers, stepping and cultured stones
• Maximum cutting depth: 3 5/8 inches
• Blade speed: 3,450 RPM
• Optional water pump which recycles the water from the tray
• Alternative dust control: vacuum tube system
• Sound pressure level: gasoline powered model exceeds 92 dBA (OSHA’s Permissible Exposure Limit for an 8-hour time-weighted average is 90 dBA)
• Weight of saw: 131 pounds

EDCO, Inc. electric (Model HSS-14-1.5B) and gasoline (Models HSS-14-5.5H and HSS-14-6.5H) hardscape masonry saws with 14-inch blade and water connection

• Used for cutting interlocking pavers, brick, stepping and cultured stones, including 4" retaining wall block and brick
• Maximum cutting depth: 4 ½ inches
• Alternative dust control: vacuum tube system
• Sound pressure level: greater than 85 dBA and likely to exceed 90 dBA (OSHA’s Permissible Exposure Limit for an 8-hour time-weighted average)
• Weight of saw: 155 pounds

(verified 11/2009)

EDCO, Inc. electric (Model BB-14-1.5B) and gasoline (Models BB-14-5.5H, BB-14-6.5H and BB-14-9H) masonry saws with 14-inch blade and water connection

• Used for cutting interlocking pavers, brick, stepping and cultured stones, and will accommodate 16" blocks
• Maximum cutting depth: 5 inches
• Alternative dust control: vacuum tube system
• Sound pressure level: greater than 92 dBA (OSHA’s Permissible Exposure Limit for an 8-hour time-weighted average is 90 dBA)

(verified 11/2009)

EDCO electric (Models MS-20-5B and MS-20-7.5H) gasoline (GMS-20-9H and GMS-20-11H) masonry saws with 20-inch blade and water connection

• Used for cutting interlocking pavers, bricks, stepping and cultured stones
• Maximum cutting depth: 8 inches
• Alternative dust control: belt driven diaphragm water pump for wet cutting is standard
• Sound pressure levels: exceeds 92 dBA (OSHA’s Permissible Exposure Limit for an 8-hour time-weighted average is 90 dBA)

(verified 11/2009)

MK Diamond Products, Inc. BX-4 stationary masonry saw with water misting dust control and 14-inch blade

• Used to cut a variety of masonry types including, cinder block, slump stone block, wall brick, paver brick, concrete block and cylinders, roofing tile, marble, granite, decorative rock or almost any other non-ferrous material
• Cost: $940 (verified 2/2011)
• Power requirements: 120 volts, 15 amps
• Horsepower: 1 ¾
• Maximum cutting depth: 5 inches
• Blade speed (RPM): 3,500
• Sound pressure level: not available but likely to exceed 90 dBA (OSHA’s Permissible Exposure Limit for an 8-hour time-weighted average)
• Weight of saw: 70 pounds (portable)

MK Diamond Products, Inc. MK-2000 series stationary masonry saws with water misting dust control and 14-inch blade

• Used for cutting pavers, brick, block and other masonry materials
• Maximum cutting depth: 5 inches
• Sound pressure level: not available but likely to exceed 90 dBA (OSHA’s Permissible Exposure Limit for an 8-hour time-weighted average)
• Pro models are designed to be moved with a forklift 

(verified 11/2009)

MK Diamond Products, Inc. MK-5000 series stationary masonry saws with water misting dust control

• Used for cutting a variety of masonry materials including, cinder block, slump stone block, wall brick, paver brick, concrete block and cylinders, roofing tile, marble, granite and decorative rock
• Blade diameter: 20 inches (blade guards for use with 14 and 24 inch blades are available for some models)
• Maximum cutting depth with 20-inch blade: 8 inches (5 inches with 14-inch blade, 10 inches with 24-inch blade)
• Sound pressure level: not available but likely to exceed 90 dBA (OSHA’s Permissible Exposure Limit for an 8-hour time-weighted average)

(verified 11/2009)

*Costs with 20-inch blade guard

**Blade speed is the number shaft revolutions per minute for a 20-inch blade

MK Diamond Products, Inc. MK-5010 Super-Matic series stationary masonry saws with water misting dust control

• Used for cutting a variety of masonry materials including, cinder block, slump stone block, wall brick, paver brick, concrete block and cylinders, roofing tile, marble, granite, decorative rock
• Blade diameter: 24 inches (blade guards for use with 14 and 20 inch blades are available for some models)
• Maximum cutting depth with 24-inch blade: 10 inches (5 inches with 14-inch blade, 8 inches with 20-inch blade)
• Weight of saw: 513 pounds
• Horsepower: 10
• Sound pressure level: not available but likely to exceed 90 dBA (OSHA’s Permissible Exposure Limit for an 8-hour time-weighted average)

(verified 11/2009)

*Costs with 24-inch blade guard

**Blade speed is the number shaft revolutions per minute for a 24-inch blade

Husqvarna Portasaw MS 355 series stationary masonry saws with water spray dust control

(Photo courtesy of Husqvarna AB Construction Division)

• Used for sawing of masonry and refractory materials such as brick and block
• Blade diameter: 14 inches
• Maximum cutting depth: 5 inches
• Sound pressure level: not available but likely to exceed 85 dBA (OSHA’s Permissible Exposure Limit for an 8-hour time-weighted average is 90 dBA)

(verified 11/2009)

*Three phase motor is available upon request

Wet dust suppression systems create a cleaner, more efficient means of masonry cutting. 

Dust suppression increases the visibility and the comfort of workers using the equipment and, depending on the configuration, may reduce site cleanup times Improved worker visibility and comfort may in turn result in less fatigue for the worker and greater productivity. 

To achieve maximum dust suppression and exposure reductions the equipment must be maintained, workers trained on the proper use of the equipment, and use must be in compliance with applicable local, state or federal regulations.  Things to consider:

• Dust suppression avoids exposing other workers, members of the public, adjacent property, cars and building occupants to silica dust., and reduces the risk of  liability and time-consuming disputes.
• “Concern that excess shrinkage as the units dry might lead to cracks has led some overly cautious specifiers to prohibit wet cutting. The bottom line is that the amount of water added to the unit during site cutting is insignificant, in terms of shrinkage. This was clarified in the ACI 530.01-05/ASCE6-05/TMS 602-05 Specification for Masonry Structures. The article on wetting concrete masonry units includes this sentence: “Wet cutting is permitted.”  http://www.imiweb.org/imi_toolkit/pdf/ClarificationWetCutting.pdf

Some additional issues to consider:

• Access to electricity (if electrical equipment) and a water supply.
• The time that may be required to allow masonry materials to dry after cutting and before use, which will depend on the material, the amount of water used and the application.
• The use of water as a dust control increases the risk of shock when electricity is used in the same area. Electrical cords and extensions must be rated for the tool's power requirements, be regularly inspected, and used in combination with ground fault interrupt circuits.
• The need to maintain a work area free of debris -- cutting debris that is not bagged and removed from the work area while wet may become airborne once dried, posing an inhalation hazard to anyone in the area.
• Excess water -- use of water controls may result in wet and slippery ground and walking surfaces. During cold weather this may lead to the formation of ice and an increased risk of slips, trips and falls.  Depending on the system, wet cutting can result in run-off that may need to be controlled.

The use of gasoline-powered equipment poses the risk of carbon monoxide exposure, particularly in areas where airflow is reduced. Steps to control exposure are important because the gas is invisible, odorless and tasteless. Poisoning by carbon monoxide can occur quickly indoors, but working outdoors does not ensure operators won’t be overcome. Small, inexpensive personal monitors can be worn by the operator to warn of unacceptable exposures.

Stationary masonry saws may generate sound levels that are greater than 90 decibels, the OSHA Permissible Exposure Limit (PEL).. Hearing protection should be worn when using a masonry saw unless the manufacturer specifies that the noise produced by the saw is below the PEL or  an industrial hygienist has conducted noise monitoring and indicated that hearing protection is not required.

Use of large diameter blades, high torque, and resistance to cutting may create hazards associated with flying debris – however, this is less likely to occur with a stationary saw than a portable saw since there is less likely to be kick-back.