Wet Abrasive Blaster

A wet abrasive blaster is an equipment used to pressure clean, texture or abrade surfaces with a blasting media mixed with water.

Description:

Using sand or alternative abrasives to clean, texture or abrade concrete, masonry materials or painted materials generates large amounts of dust which may contain high levels of crystalline silica and creates a hazard for everyone in the vicinity. Using an abrasive containing little or no silica does not eliminate the hazard when silica-containing paint, concrete or masonry is cleaned or abraded. Wet abrasive blasting is a control option for dust generated while cleaning, texturing or abrading silica-containing materials. These controls mix water and abrasive before propelling them toward the work surface and reduce airborne dust levels.

If properly designed and used, exposures can be reduced significantly.  If use is brief and intermittent, this may reduce exposures enough that a respiratory protection program isn’t required. Continuous use may exceed the OSHA Permissible Exposure Limit, however, even with the use of water.

Water Induction Nozzle (WIN®) double venturi bore nozzles

  • Used for wet or dry blasting with existing pressure blast equipment
  • Water supply: ¾ to 6 quarts per minute through a 3/4 inch hose connection
  • Sound pressure level: Not available but likely to exceed 90 dBA (OSHA’s Permissible Exposure Limit for an 8-hour time-weighted average)
 
Model Number
Costs
Thread Style
Bore Diameter, inches
Air Supply Requirement, cfm
Length, inches
WIN-3
$320 - $553
1-1/4 – 11-1/2 N.P.S.M.
3/16
45
5
WIN-4
¼
80
5-3/4
WIN-5
5/16
140
6-1/4
WIN-6
3/8
200
6-3/4
WIN-7
7/16
255
8-1/4
WIN-8
½
340
9
WIN-450
$392 - $555
2 – 4-1/2 U.N.C.
¼
80
5-3/4
WIN-550
5/16
140
6-1/4
WIN-650
3/8
200
6-3/4
WIN-750
7/16
255
8-1/4
WIN-850
1/2
340
9
cfm = cubic feet per minute
 

 SN BP200 Water Induction Nozzle (WIN®) double venturi bore nozzles

  • Used for wet or dry blasting with existing pressure blast equipment
  • Water supply: ¾ to 6 quarts per minute through a 3/4 inch hose connection
  • Sound pressure level: Not available but likely to exceed 90 dBA (OSHA’s Permissible Exposure Limit for an 8-hour time-weighted average)
  
Model Number
Costs
Thread Style
Bore Diameter, inches
Length, inches
SN BP200 WIN-3
387 - $540
1-1/4 – 11-1/2 N.P.S.M.
¼
5.75
SN BP200 WIN-5
5/16
6.25
SN BP200 WIN-6
3/8
6.74
SN BP200 WIN-7
7/16
8.27
SN BP200 WIN-8
1/2
9.05
SN BP200 WIN-450
2 – 4-1/2 U.N.C.
¼
5.75
SN BP200 WIN-550
5/16
6.25
SN BP200 WIN-650
3/8
6.74
SN BP200 WIN-750
7/16
8.27
SN BP200 WIN-850
1/2
9.05
 
 
 
Mini Water Induction Nozzle (WIN®) series tungsten carbide nozzles
  • Used for wet or dry blasting with existing pressure blast equipment
  • Water supply: ¾ to 6 quarts per minute through a 3/4 inch hose connection
  • Sound pressure level: Not available but likely to exceed 90 dBA (OSHA’s Permissible Exposure Limit for an 8-hour time-weighted average)
  
Model Number
Costs
Thread Style
Bore Diameter, inches
Length, inches
Mini WIN-2
$279
3/4-14 N.P.S.M.
1/8
3-1/2
Mini WIN-3
3/16
Mini WIN-4
¼
Mini WIN-5
5/16
Mini WIN-6
3/8

 

  

  
Torbo wet abrasive blasting systems with lower volume tanks
  • Used for a wide variety of surface cleaning and wet abrasive blasting work
  • Standard blasting media mixture: 80% blasting media / 20% water
  • Blasting hose: 1-1/4 inch
  • Sound pressure level: Not available but likely to exceed 90 dBA (OSHA’s Permissible Exposure Limit for an 8-hour time-weighted average)
Models
Costs
Volume of Vessel, cubic feet
Air Supply
Water Supply, pounds per square inch
Blasting Media Consumption Rate, cubic feet per hour
Weight, pounds
Torbo S080
Call for a quote
2.6
70 to 175 cfm at 56 to 140 psi
0 to 170
0.6 to 4.5
1,100
Torbo M080
Call for a quote
2.6
70 to 350 cfm at 56 to 140 psi
0 to 170
0.6 to 4.5
1,100
Torbo S120
Call for a quote
4.2
70 to 175 cfm at 56 to 140 psi
0 to 170
0.9 to 9
1,100
Torbo M120
$18,000 - $21,000
4.2
70 to 350 cfm at 56 to 140 psi
0 to 170
0.9 to 9
1,100
Torbocar AC25
Call for a quote
2.6
106 cfm at 102 psi*
Onboard water tank
0.6 to 4.5
4,400
Torbocar AC37
Call for a quote
4.2
134 cfm at 102 psi*
Onboard water tank
0.9 to 9
4,400
cfm = cubic feet per minute
psi = pounds per square inch
*air is supplied by an onboard compressor
  
 
Torbo wet abrasive blasting systems with higher volume tanks
  • Used for a wide variety of surface cleaning and wet abrasive blasting work
  • Standard blasting media mixture: 80% blasting media / 20% water
  • Blasting hose: 1-1/4 inch
  • Blasting media consumption rate: 0.9 to 9 cubic feet per hour
  • Sound pressure level: Not available but likely to exceed 90 dBA (OSHA’s Permissible Exposure Limit for an 8-hour time-weighted average)
Models
Costs
Volume of Vessel, cubic feet
Air Supply
Water Supply, pounds per square inch
Weight, pounds
Torbo L200
Call for a quote
7.0
70 to 385 cfm at 56 to 140 psi
0 to 170
2,200
Torbo XL200
Call for a quote
7.0
70 to 385 cfm at 56 to 140 psi
0 to 170
2,200
Torbo L320
Call for a quote
11.4
70 to 385 cfm at 56 to 140 psi
0 to 170
2,200
Torbo XL320
$32,000 - $34,000
11.4
70 to 385 cfm at 56 to 140 psi
0 to 170
2,200
Torbocar AC52
Call for a quote
7.0
219 cfm at 102 psi*
Onboard water tank
4,400
Torbocar AC76
Call for a quote
11.4
268 cfm at 102 psi*
Onboard water tank
4,400
cfm = cubic feet per minute
psi = pounds per square inch
*air is supplied by an onboard compressor
 
 
  
Hydroblaster Abrasive Application Unit (AAU)
Used with a separate pressure washer to create a wet abrasive blasting system
Cost: $995
Media capacity: 2.7 cubic feet
Weight: 52 pounds

Risks Addressed:

Silica dust exposure may cause silicosis or lung scarring with prolonged exposure.  Silicosis is an incurable, sometimes fatal, disease.  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. This is one-half of the OSHA standard when the dust is pure silica, but still twice the ACGIH-recommended threshold limit value (TLV) of 0.025 mg/m3.  Silica has also been associated with lung cancer and chronic obstructive pulmonary disease (COPD).


How Risks are Reduced:

The abrasive media, which has traditionally been sand, is combined with water prior to leaving the nozzle. In some cases, the water is the propellant and in some cases compressed air is the propellant. When the abrasive media has been mixed with water, the fine dust and silica particles that exist in the abrasive and result from the media impacting the target material are heavier and settle to the ground before they can be inhaled. Silica and dust are only hazardous if inhaled and are not hazardous for skin contact. As long as the dust does not become airborne, the hazard is reduced. 

Other hazardous materials, such as lead in paint may also be present in dust from abrasive blasting.  Any control that reduces dust exposure will reduce exposures to all contaminants in the abrasive and in the surface being abraded.

 

Evaluations of Torbo and Boride Products wet abrasive blasting systems have demonstrated significant reductions in respirable dust and respirable silica exposure, compared to dry abrasive blasting. The studies used abrasive media containing a reduced amount of fine particulate and were therefore unable to identify the portion of the respirable silica and dust exposure reductions attributable to the use of wet methods versus fine particulate content.

Effects on Productivity:

 

Compared to abrasive blasting without water, wet abrasive blasting is expected to improve productivity by increasing visibility, reducing work site cleanup and reducing worker cleanup.
 
Wet abrasive blasting also avoids exposing other workers, members of the public, adjacent property, cars and building occupants, which can increase liability and time-consuming disputes.  Improved worker comfort is a result of reduced airborne dust which may in turn result in less fatigue for the worker and greater productivity.  In some cases, particularly where abrasive blasting is intermittent, wet methods may be adequate to reduce the need to wear a respirator and the need for an employer respiratory protection program. 
 
Some additional issues should be considered. Time may be required to allow materials to dry after wet abrasive blasting and before further work, which will depend on the material, the amount of water used and the application. The abrasive blaster needs to be located near a source of compressed air and a source of water.

Additional Considerations:

Abrasive blasting performed in the state of California must employ engineering controls, either wet methods or local exhaust ventilation, unless the employer can show that exposures are below the permissible exposure limit (subchapter 4, article 4, section 1530.1). New Jersey has a similar prohibition of dry cutting or grinding of masonry (Chapter 172).

The use of water-based 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. Debris and abrasive blasting media that are not removed from the work area while wet may become airborne once dried, posing an inhalation hazard to anyone in the area. Maintain a work area free of debris and excess water to reduce the risk of these hazards.
 
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, replaced when damaged, and used in combination with ground fault interrupt circuits.
 
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 should be worn by the operator to warn of unacceptable exposures.
 
Abrasive blasting equipment frequently generates sound levels that are greater than 90 decibels, the OSHA Permissible Exposure Limit (PEL), and hazardous. Hearing protection should be worn when performing abrasive blasting unless an industrial hygienist has conducted noise monitoring and indicated that hearing protection is not required.
 
As is the case with any construction equipment, users should follow manufacturer safety recommendations and comply with any applicable local, state or federal regulations.  When blasting lead painted surfaces or where environmental regulations requires spent abrasive be disposed of as hazardous waste for any reason, wet blasting may complicate disposal and require containment of runoff water.

Hazards Addressed:

Availability

SN BP200 Water Induction Nozzle (WIN®) double venturi bore nozzles
To obtain information, visit http://www.surfaceprepsolutions.com or contact 1-800-899-3872

Water Induction Nozzle (WIN®) double venturi bore nozzles
To obtain information, visit http://www.surfacepreparation.com or contact 1-800-899-3872

Torbo wet abrasive blasting systems
contact 1-817-685-7090 sales@torbousa.com

Hydroblaster Abrasive Application Unit (AAU)
To obtain information, visit http://www.hydroblaster.com or contact 1-800-247-8424 info@hydroblaster.com

Return on Investment

To calculate the return on investment (ROI) for your specific application, please visit our Return on Investment Calculator. While a specific ROI example has not been developed for this particular solution, the ROI Calculator provides a useful tool and guidance on how to generate your own on investment analysis.