Hand-held Surface Grinders with Vacuum Dust Control

A surface grinder with local exhaust ventilation is a hand-held tool that removes dust while smoothing concrete surfaces.

Description:

Surface grinders are often used to smooth poured concrete surfaces after the forms have been removed. Grinding concrete generates a large amount of dust which is likely to contain high levels of crystalline silica and creates a hazard for everyone in the vicinity.  Vacuum dust controls exist for surface grinders.  These controls consist of a vacuum, with a disposable filter (a high efficiency particulate air, HEPA, filter is often an option and recommended where practical), attached to a shroud that is compatible with the grinder and partially encloses the blade.  The vacuum draws air and dust from the blade, the point of dust generation, into the shroud where it is transported through tubing into the vacuum's bag or reservoir. Cyclonic pre-separators, either as an integral part of the vacuum or as a separate unit, should be used to collect the majority of the particles before they reach the filters. The use of a cyclonic pre-separator reduces the amount of dust that collects on the filter, which increases the useful life of expensive filters and helps to maintain the vacuum’s initial airflow rate.

Pearl Abrasive Company Vacu-Guard dust containment systems for angle grinders

  • Used with a variety of angle grinders and vacuums to reduce dust levels while grinding concrete surfaces
  • Compatible with most Dewalt, Black & Decker, Bosch, Makita, Metabo, Milwaukee and Hitachi grinders (must specify grinder make and model when ordering)
  • Optional carbide wear pads protect sliding surface from excessive wear, thus increase useful life
  • Constructed of durable and light-weight aluminum
 
Models
Costs
Maximum Blade Diameter, inches
Vacuum Take-Off Diameter, inches
Vacu-Guard Standard
$133
4-1/2
1-1/2
$178
7
2
Vacu-Guard with Carbide Protection
$162
4-1/2
1-1/2
$211
7
2

(verified 11/2009) 
 
 
Hilti DG 150 Diamond Grinder System with Power Conditioner
  • Used for concrete and mineral surface grinding
  • Cost: $2,004 (verified 11/2009) 
  • Power requirements: 120 volts, 15 amps
  • Vacuum take-off diameter: 1.42 inches (36 millimeters)
  • Weight: 9 pounds
  • Wheel speed (no load): 4,700 and 6,600 RPM
  • Sound pressure level: 88 dBA (OSHA’s Permissible Exposure Limit for an 8-hour time-weighted average is 90 dBA; at 85 dBA employees must be enrolled in a hearing conservation program)
 
 
 
Hilti VC 40-U wet/dry vacuum cleaner
  • Available models: the "HEPA Vacuum Set" and the "Universal Vacuum." The filter that comes with the "Universal Vacuum" model removes less than 95 percent of particles compared to 99.97 percent captured by a HEPA filter. The "HEPA Vacuum Set" is recommended and should be used in combination with fleece bags to extend the useful life of the filter.
  • Cost: $962 (with “HEPA Vacuum Set”) (verified 11/2009) 
  • Cost: package of 5 replacement fleece bags: $63 (verified 11/2009) 
  • Air flow rate (maximum): 129 cubic feet per minute
  • Length of vacuum hose: 16.4 feet
  • Dust capacity: 9.5 gallons or 88 pounds
  • Weight: 32.2 pounds
  • Filter cleaning: automatic, every 15 seconds
  • Power requirements: 120 volts, 10 amps
 
 
Dustcontrol, Inc. suction casings for diamond cup grinding discs
  • Used with a variety of angle grinders and vacuums to reduce dust levels while grinding concrete surfaces
  • Compatible with most angle grinders (must specify blade diameter, mounting collar diameter and mounting collar to grinding surface height when ordering)
 
Model Number
Costs
Maximum Blade Diameter, inches
Mounting Collar Diameter, inches
Mounting Collar to Grinding Surface Height, inches
Vacuum Take-Off Diameter, inches
6681
$202
4-1/2
1.6 to 1.9
1.9 to 2.1
1-1/4
6682
$202
5
1.9 to 2.8
1.9 to 2.8
1-1/4
6673
$226
6
3
1.5 to 2.4
1-1/4
6683
$226
7
2.1 to 2.4
2.5 to 2.8
1-1/2
6684
$226
7
2.4 to 2.6 and 2.9 to 3
2.5 to 3.4
1-1/2

 

 

  
Dustcontrol, Inc. Single Phase Dust Extractors
  • Filtration: cyclonic separator, a fine filter, rated to remove 99.9 percent of particles, followed by a HEPA filter, rated to remove 99.95 percent of 0.3 micron particles
  • Features a “reverse air pulse cleaning system”
  • Features a lamp that indicates significant loss of air flow (all models except DC 1800)
  • When ordering Model DC 2900c specify a “rental” unit to receive an operation timer and inlet plug for a negative pressure gauge that can be used to monitor air flow
  • Vacuum hose inlet diameter: 2 inches
  • Sound pressure level: 68 to 75 dBA
 
 
Dustcontrol, Inc. DC 3800c Three Phase Dust Extractors
  • Recommended for use with jack hammers, saws and grinders with up to 9-inch disks and up to 65 feet of hose. 
  • Filtration: cyclonic separator, a 19.5 square foot fine filter, rated to remove 99.9 percent of particles, followed by a 16.2 square foot HEPA filter, rated to remove 99.995 percent of 0.3 micron particles
  • Features a “reverse air pulse cleaning system”
  • Features a lamp that indicates significant loss of air flow
  • Air flow rate: 156 cubic feet per minute
  • Maximum static pressure: 120 inches of water
  • Vacuum hose inlet diameter: 2 inches
  • Sound pressure level: 75 dBA 

 

 
Dustcontrol, Inc. DC 5900c Three Phase Dust Extractors
  • Recommended for use with two handheld grinders or one floor grinder. 
  • Filtration: cyclonic separator, a 90.4 square foot fine filter (DC 5800 PTFE has a 53.8 square foot Teflon filter which is ideal for concrete dust), rated to remove 99.9 percent of particles, followed by a 26.9 square foot HEPA filter, rated to remove 99.995 percent of 0.3 micron particles
  • Features a “reverse air pulse cleaning system”
  • Features a lamp that indicates significant loss of air flow
  • Vacuum hose inlet diameter: 2 inches
  • Dust capacity: 15.5 gallons in plastic bags
  • Sound pressure level: 75 dBA
Models
Costs
Maximum Air Flow Rate, cubic feet per minute
Maximum Static Pressure, inches of water
Vacuum Hose Inlet Diameter, inches
Vacuum Power Requirements (all are 3 phase)
Vacuum Weight, pounds
DC 5900c 10 HP
$9,793
353
124
3
460 volts, 16.3 amps
419
DC 5900c 18.5 HP S
$11,925
330
181
4-1/4
460 volts, 23.9 amps
440
DC 5900c PTFE
$11,376
353
124
3
230 volts, 32.6 amps or 460 volts, 16.3 amps
419

(verified 11/2009) 

 

Compatible Blastrac vacuums: BDC-1216, BDC-1324 and BDC-165P
  • Filtration: main filter removes 99.7 percent of particles, a HEPA filter kit can be purchased for $482 and replacement HEPA filters can be purchased for $329
Models
Costs
Air Flow Rates, cubic feet per minute
Maximum Static Pressure, inches of water
Dust Capacity, gallons
Dust Capacity, pounds
Vacuum Power Requirements
Vacuum Weight, pounds
BDC-1216*
$1,695
180
80
10.5
90
120 volts, 17 amps
75
BDC-1324
$3,100
282
80
10.5
90
120 volts, 20 amps
77
BDC-165P
$7,100
325
71
Not available
243
Gasoline, 6.5 horsepower
200
 
(verified 11/2009) 
 
*Blastrac technical support staff has indicated that while the BDC-1216 works with the above mentioned grinders, the larger vacuums have significantly greater flow rates and provided noticeably better dust collection.
 
  
CS Unitec/FLEX LD1509FRD 5-inch lightweight concrete grinder with dust collection shroud
  • Used to remove epoxy, paint, mastic, mud and other coatings from concrete surfaces
  • Cost: $604 (with premium diamond grinding wheel) (verified 11/2009) 
  • Power Requirements: 120 volts, 11 amps
  • Maximum blade diameter: 5 inches
  • Maximum blade speed: 10,000 RPM
  • Vacuum take-off diameter: 1-1/4 inches
  • Weight: 6 pounds
  • Sound pressure level: Not available but likely to exceed 90 dBA (OSHA’s Permissible Exposure Limit for an 8-hour time-weighted average)
 

 Compatible CS Unitec, Inc. vacuums: CS 1225 and CS 1500

  • Air flow rate: 130 cubic feet per minute
  • Water lift: 98 inches
  • Available bags:
    • Plastic is ideal for concrete dust
    • Paper is ideal for general debris
    • Water permeable is ideal for concrete slurry
  • Power requirements: 120 volts, 11 amps
  • Filtration: standard filter removes 99.93 percent of 3.0 micron particles, HEPA filter can be purchased for $387
Models
Costs
Dust Capacity, gallons
Vacuum Weight, pounds
CS 1225
$597
6.6
24.3
CS 1500
$775
13
31

(verified 11/2009) 

 
Industrial Contractors Supply (ICS), Inc. Surface Grinding Dust Shrouds
  • Used with a handheld grinder to reduce dust during the grinding and polishing of concrete
  • Compatible with most Metabo, Hitachi, Makita, Bosch, Ryobi and Dewalt grinders (must specify grinder make and model when ordering)
  • Constructed of durable steel with adjustable rubber seal along the edge
  • Vacuum take-off diameter: 2 inches
  • 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
Blade Diameter Range, inches
7-inch Surface Edging Dust Guard
$320
7 to 9
5-inch Surface Corner Dust Guard
$235
4.5 to 5
 
 
 
Industrial Contractors Supplies, Inc. vacuums
  • Maximum static pressure: 97 inches of water
Model
Costs
Air Flow Rate, cubic feet per minute
Dust Capacity, pounds
Vacuum Power Requirements
Sound Pressure Level, dBA
Kut-N-Go
$520
136
40
120 volts, 8.5 amps
67
DC-1-MOTOR
$600
136
60
120 volts, 8.5 amps
67
DC-2-MOTOR
$880
271
120
120 volts, 17.5 amps
78
DC-3-MOTOR
$1,170
407
120
120 volts, 19.5 amps
79

(verified 11/2009) 

 
Industrial Contractors Supplies, Inc. 30 Gallon HD Poly Cyclone Separator
  • Cyclonic separator that can be connected to ICS DC-2-MOTOR or DC-3-MOTOR vacuums to remove larger particles and increase the time between changing vacuum bags and filters.
  • Cost: $550 (verified 11/2009) 
  • Dust capacity: 140 pounds
 
Dustless Technologies DustBuddie Dust Containment Shroud for hand grinders
  • Used with a handheld grinder for dust collection during surface grinding
  • Cost: $100 (verified 11/2009) 
  • DustBuddie D1835 fits most 4 to 5 inch hand grinders, DustBuddie D1850 fits most 6 to 9 inch grinders
  • Vacuum take-off diameter: 2 inches (with adapter)
  • Constructed from light weight, see-thru, polycarbonate plastic
  • Sound pressure level: Not available but likely to exceed 90 dBA (OSHA’s Permissible Exposure Limit for an 8-hour time-weighted average)

Bosch Dust Extraction Attachments for Surface Grinders
  • Used with handheld grinders to reduce dust during concrete surface grinding
  • Vacuum take-off diameter: 1-5/8 inches
  • Bosch grinders compatible with dust extraction attachment 18SG-5E: 1800, 1801, 1803EVS, 1806E, 1810PS, 1810PSD, 1811PS, 1811PSD, 1821 and 1821D
  • Bosch grinders compatible with dust extraction attachment 18SG-7: 1853-5, 1853-6, 1873-6, 1873-8, 1873-8D, 1893-6, 1893-6D, 1894-6 and 1894-6D
Models
Costs
Wheel Diameters, inches
Weight, pounds
18SG-5E
$50 to $76
4, 4-1/2 and 5
0.5
18SG-7
$100 to $180
7
1.75
 
(verified 11/2009)  
 

 Bosch Airsweep™ Wet/Dry Vacuum

  • Cost: $530 (verified 11/2009) 
  • Air flow rate: 130 cubic feet per minute
  • Water lift: 100 inches
  • Power requirements: 120 volts, 11 amps
  • Weight: 42 pounds
  • Filtration: standard set of two filters remove 99.93 percent of 3.0 micron particles, set of HEPA filter can be purchased for approximately $200
  • Sounds pressure level: 69 dBA
 
 
Pullman-Ermator single phase electric dust extractors
  • Filtration: cyclonic separator, coarse filter and HEPA filter capable of removing 99.97% of 0.3 micron particles (the most penetrating size)
  • Sound pressure level: 75 dBA or less (OSHA’s Permissible Exposure Limit for an 8-hour time-weighted average is 90 dBA)
Models
Costs
Air Flow Rates, cubic feet per minute
Static Pressure, inches of water
Dust Collection
Filter Area (coarse/HEPA), square feet**
Horse
power
Power Requirements
Weight, pounds
S1200
$2,061
118
90
Longopac® bag system*
6.6/9.1
1.7
120 volts, 9.6 amps or 230 volts, 4.4 amps
62
S1300
$1,559
118
90
3.4 gallons
16/9.1
1.7
120 volts, 9.6 amps or 230 volts, 4.4 amps
62
S2400
$2,479
235
90
Longopac® bag system*
11/18.34
3.4
120 volts, 19.2 amps or 230 volts, 8.8 amps
62
S2800
$2,210
235
90
9.8 gallons
11/18
3.5
120 volts, 8.8 amps
99
 
(verified 11/2009) 
 
* Longopac® bag system uses a 70 foot long plastic tube that is divided and sealed at the desired length
 
** Greater area allows more time between filter cleaning or replacement
 
 
Pullman-Ermator three phase electric dust extractors
  • Filtration: cyclonic separator, coarse filter and HEPA filter capable of removing 99.97% of 0.3 micron particles
  • Dust collection: Longopac® bag system which uses a 70 foot long plastic tube that is divided and sealed at the desired length
  • Sound pressure level: 75 dBA or less (OSHA’s Permissible Exposure Limit for an 8-hour time-weighted average is 90 dBA)
Models
Costs
Air Flow Rates, cubic feet per minute
Static Pressure, inches of water
Available Hose Diameters, inches
Filter Area (coarse/HEPA), square feet*
Horsepower
Power Requirements
Weight, pounds
T3000
$5,091
153
125
2
23/6.6
4.8
230 volts, 7.5 amps
183
T3500
$7,386
188
125
2 or 3
15.1/26.9
4.8
230 volts, 7.5 amps
313
T7500
$10,603
353
110
2 or 3
24.8/53.8
10.4
230 volts, 24.2 amps
417
T8600
$9,928
353
110
2 or 3
24.8/53.8
10.4
480 volts, 11.9 amps
439
T12600
$14,726
647
110
3
41/108
17.4
480 volts, 21 amps
716
 
(verified 11/2009) 
 
* Greater area allows more time between filter cleaning or replacement
 
 
Pullman-Ermator cyclonic pre-separators
  • Remove approximately 90 percent of particulate and can be used with Pullman-Ermator or other dust extractors
  • Dust collection: Longopac® bag system which uses a 70 foot long plastic tube that is divided and sealed at the desired length
Models
Costs
Inlet Diameter, inches
Weight, pounds
C3000
$1,001
2
49
C5500
$1,912
3
130
 
(verified 11/2009) 
 
 

 


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 shrouds partially enclose the blades of the grinders and have a connection for a vacuum system.  When a vacuum system is connected to the shroud, air is drawn into the shroud and past the blade, capturing dust and silica at the point of dust generation.  These systems capture dust and silica near the source, reducing concentrations in the worker's breathing zone and his or her exposure, as long as the vacuum provides an adequate air velocity to capture rapidly moving particles of dust and silica near the source, concentrations in the worker's breathing zone and his or her exposure will be reduced.  For continuous use, a respiratory protection program and respirators may be required.

In an evaluation of a Vacu-Guard shroud with a Dustcontrol 2700c vacuum, Echt and Sieber reported 8-hour TWA quartz exposures ranged from 0.036 mg/m3 to 0.13 mg/m3,” or from 1.4 to 5.2 times the current ACGIH TLV of 0.025 mg/m3. While still greater than the TLV, these exposures represent a significant reduction compared to uncontrolled exposures reported in the literature.

In an evaluation of a Hilti DG 150 6-inch grinder with a Hilti VCD 50 vacuum, Akbar-Khanzadeh et al. observed greater than 99 percent reduction in respirable silica with an average concentration of 0.155 mg/m3 or 6 times the ACGIH TLV.
 
In an evaluation of engineering controls, Croteau et al. observed 70 to 95 percent reductions in respirable dust, compared to use of no control, during the use of a surface grinder with local exhaust ventilation.

Effects on Productivity:

Echt and Sieber concluded that there was “a learning curve associated with the use of the vacuum cleaner and shroud” but “the tasks of changing bags and cleaning the vacuum cleaner filter do not seem to interfere with the productivity of the concrete finisher.” They also stated that use of the vacuum system reduced cleanup required by other trades and allowed them to work in the vicinity of the concrete finishers.
 
Vacuum dust control systems can have either positive or negative effects on productivity, but definitely improve the quality of the work by capturing large amounts of airborne dust, which allows a cleaner, more efficient means of removing mortar.
 
Dust capture also reduces site cleanup times.  Dust capture 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 grinder use is intermittent, vacuum dust control 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. Changing vacuum bags takes time, which will depend on the amount of cutting being done and the size of the vacuum bag or hopper. Workers will need to adapt to working with a vacuum hose attached to the tool.  Grinder and vacuum energy requirements may exceed the capacity of a single standard 20 amp circuit when combined requiring access to two circuits or special wiring.

Additional Considerations:

Ventilation for construction tools is often misunderstood. There are some key concepts that can help:

  • The vacuum must be located as close to the dust generation as possible to be effective. A shroud may be needed to contain the dust so the vacuum can capture it. The shroud must be kept as close to the work surface as is practical to provide adequate dust capture. The shroud should be connected to the vacuum with 2-inch, or greater, diameter tubing with a relatively smooth interior.
  • The particles that can do the most damage in the lungs are small enough to penetrate the filters found on many shop vacuums. Additionally, some inexpensive shop vacuums pull the dust through the motors, which can destroy the vacuum on really dusty jobs, eliminating any initial cost savings.
  • For dust containing harmful particles like silica, it is important to use as high efficiency filters as practical. The best available are called HEPA (High Efficiency Particle Air) filters because they capture 99.97% of the most penetrating particles. But HEPA filters also create a greater pressure drop and decrease in air flow rate because it is more difficult to pull air through these denser filters so capture velocity may be reduced. They also require pre-filters to extend the life of the HEPA filters, which are more expensive than other filters. Studies have shown that it may be more effective to direct the exhaust air out of the work area than to attempt to add HEPA filtration for a tool where it isn't an integral part already. HEPAs require routine cleaning or disposal of prefilters, which can cause exposures to those performing the filter maintenance.
  • For operations that generate large amounts of dust, cyclonic collection units, if available, may be the best solution. Rather than require more expensive filters and bags that must be frequently changed, cyclonic units spin the particles and drop them into cheap bags that need to be replaced far less frequently because loading of the bags does not cause a pressure drop.
  • Vacuum performance must be monitored on a regular basis. A vacuum with a pressure gauge allows for frequent and easy monitoring of air flow. For high dust generating tasks, dust caked on the filter may reduce flow to a level where it no longer provides adequate dust capture. Automatic and manual filter shakers, coarse pre-filters and cyclonic collections units are available with some vacuums and may help maintain the air flow rate.
Large electric vacuums commonly require 20 amp electrical circuits in addition to the 20 amp circuit used for the electric grinder.  Cords and extensions must be rated for the tool's power requirements, be inspected regularly, 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. Small, inexpensive personal monitors should be worn by the operator to warn of unacceptable exposures.  When working in an enclosed area, it is preferable to use an electronic power tool as opposed to gasoline in order to avoid carbon monoxide over exposures.
 
Grinders frequently generate sound levels that are greater than 90 decibels, the OSHA Permissible Exposure Limit (PEL), and hazardous. Hearing protection should be worn when using surface grinders 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.

Hazards Addressed:

Availability

Industrial Contractors Supply (ICS), Inc. Dust Director Shroud, Vacuums and Cyclone Separator
To obtain information, visit http://www.icscompany.net or contact 1-412-824-6933 trs@icscompany.net

Dustless Tools
To obtain information, visit grinding shrouds or contact 1-800-568-3949 http://www.dustlesstools.com/blog/contact-us/

Hilti DG 150 Diamond Grinder System with Power Conditioner and VC 40-U Wet/dry vacuum
To obtain information, visit DG 150 grinder and VC 40-U vacuum or contact 1-423-234-2111

Pullman-Ermator, Inc.
To obtain information, visit single phase electric dust extractorsp://www.ermatorusa.com and three phase electric dust extractors and c-line pre seperators or contact 1-855-736-2869 info@ermatorusa.com

NIOSH Workplace Solutions Sheet
The National Institute of Safety and Health (NIOSH) has published a series of “Workplace Solutions”, which are easy-to-understand recommendations from NIOSH research results. Related to this Construction Solution, please find more information on: Control of Hazardous Dust When Grinding Concrete

Dustcontrol, Inc.
To obtain information, visit suction casings and DC 3800c vacuum and DC 5900c or contact 1-910-395-1808 sales@dustcontrolusa.com

CS Unitec, Inc.
To obtain information, visit LD1509FR grinder and CS 1225 vacuum and CS 1500 vacuum or contact 1-800-700-5919

Pearl Abrasive Company Vacu-Guard dust containment systems for angle grinders
To obtain information, visit http://www.pearlabrasive.com or contact 1-800-969-5561 contact.pearl@pearlabrasive.com

Bosch Dust Extraction Attachments and Bosch Airsweep Wet/Dry Vacuuum
To obtain information, visit Model 18SG-5E and Model 18SG-7 and Airsweep vacuum or contact 1-877-267-2499

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.