Solution Summary: Tuckpointing Grinder with Vacuum Dust Control
Description:
Tuckpointing grinders are used to remove the mortar from between bricks prior to repointing with new mortar. Grinding mortar 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 tuckpointing grinders. A vacuum dust control (or local exhaust ventilation) for a tuckpointing grinder typically consists of a vacuum with a disposable filter (a high efficiency particulate air –HEPA–filter is recommended when practical), and a hose attached, either directly or with an adapter, to a hood or shroud that partially encloses the blade. The vacuum draws air and dust from the blade, the point of dust generation, into the hood where it is transported through the hose into the vacuum's bag or reservoir.
CS Unitec/FLEX F1509FRD 5-inch Tuck-Pointing Machine with Dust Collection
- Used to remove deteriorated mortar from the bed and head joints on brick or block structures
- Power Requirements: 120 volts, 11 amps
- Maximum blade diameter: 5 inches
- Cutting depth: adjustable up 1 inch with 5-inch blade,
- Maximum blade speed: 10,000 RPM
- Vacuum take-off diameter: 1-1/4 inches
- Weight: 8 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
Models | Dust Capacity, gallons | Vacuum Weight, pounds |
CS 1225 | 6.6 | 24.3 |
CS 1500 | 13 | 31 |
Industrial Contractors Supply (ICS), Inc. Dust Director Shroud
- Used with a grinder to remove deteriorated mortar from the bed and head joints on brick or block structures
- Cost: $195 (available for approximately $300 with a Metabo or Makita grinder) (verified 11/2009)
- Compatible with most Metabo, Rigid, Hitachi, Makita, Bosch and Dewalt grinders (must specify grinder make and model when ordering)
- Blade diameter: 4 to 6 inches
- Cutting depth: 1-1/2 inch with 6-inch blade,
- Blade width: 0.08 - 0.5 inches
- Vacuum take-off diameter: 2 inches
- Constructed from light weight aluminum
- Sound pressure level: Not available but likely to exceed 90 dBA (OSHA’s Permissible Exposure Limit for an 8-hour time-weighted average)
Industrial Contractors Supplies, Inc. vacuums
- Maximum static pressure: 97 inches of water
Model | Air Flow Rate, cubic feet per minute | Dust Capacity, pounds | Vacuum Power Requirements | Sound Pressure Level, dBA |
Kut-N-Go | 136 | 40 | 120 volts, 8.5 amps | 67 |
DC-1-MOTOR | 136 | 60 | 120 volts, 8.5 amps | 67 |
DC-2-MOTOR | 271 | 120 | 120 volts, 17.5 amps | 78 |
DC-3-MOTOR | 407 | 120 | 120 volts, 19.5 amps | 79 |
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.
- Dust capacity: 140 pounds
Dustless Technologies CutBuddie Dust Director
- Used with a grinder for dust collection during tuckpointing, crack chasing and decorative cutting
- 5-inch CutBuddie fits most 4 and 5 inch hand grinders, 7-inch CutBuddie fits most 6 to 9 inch grinders
- Cutting depth: 1-1/2 inch with 6-inch blade,
- Vacuum take-off diameter: 2 inches
- 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 5-inch Tuckpoint Grinder with Dust Extraction Port
- Used with a grinder to remove deteriorated mortar from the bed and head joints on brick or block structures
- Power requirements: 120 volts, 8.5 amps
- Blade diameter: 4 to 6 inches
- Cutting depth: 1-1/2 inch with 5-inch blade
- Maximum blade speed: 11,000 RPM
- Vacuum take-off diameter: 1.38 inches (35 millimeters)
- Weight: 6 pounds
- Sound pressure level: 89 dBA (OSHA’s Permissible Exposure Limit for an 8-hour time-weighted average is 90 dBA)
Bosch Airsweep™ Wet/Dry Vacuum
- Air flow rate: 130 cubic feet per minute
- Water lift: 100 inches
- Hose diameter: 1.38 inches (35 millimeters)
- Power requirements: 120 volts, 11 amps
- Weight: 42 pounds
- Filtration: standard set of two filters remove 99.93 percent of 3.0 micron particles, a set of HEPA filters 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 | Air Flow Rates, cubic feet per minute | Static Pressure, inches of water | Dust Collection | Filter Area (coarse/HEPA), square feet** | Horsepower | Power Requirements | Weight, pounds |
S1200 | 118 | 90 | Longopac® bag system* | 6.6/9.1 | 1.7 | 120 volts, 9.6 amps or 230 volts, 4.4 amps | 62 |
S1300 | 118 | 90 | 3.4 gallons | 16/9.1 | 1.7 | 120 volts, 9.6 amps or 230 volts, 4.4 amps | 62 |
S2400 | 235 | 90 | Longopac® bag system* | 11/18.34 | 3.4 | 120 volts, 19.2 amps or 230 volts, 8.8 amps | 62 |
S2800 | 235 | 90 | 9.8 gallons | 11/18 | 3.5 | 120 volts, 8.8 amps | 99 |
* 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 | 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 | 153 | 125 | 2 | 23/6.6 | 4.8 | 230 volts, 7.5 amps | 183 |
T3500 | 188 | 125 | 2 or 3 | 15.1/26.9 | 4.8 | 230 volts, 7.5 amps | 313 |
T7500 | 353 | 110 | 2 or 3 | 24.8/53.8 | 10.4 | 230 volts, 24.2 amps | 417 |
T8600 | 353 | 110 | 2 or 3 | 24.8/53.8 | 10.4 | 480 volts, 11.9 amps | 439 |
T12600 | 647 | 110 | 3 | 41/108 | 17.4 | 480 volts, 21 amps | 716 |
* Greater area allows more time between filter cleaning or replacement
Pullman-Ermator cyclonic pre-separators
- Removes 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 | Inlet Diameter, inches | Weight, pounds |
C3000 | 2 | 49 |
C5500 | 3 | 130 |
(Photo courtesy of Husqvarna Construction Division AB)
Risks Addressed:
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. For continuous use, a respiratory protection program and respirators may be required. Tuckpointing is among the dustiest tasks encountered in construction. Individual workers may generate upwards of 60 pounds per day of dust. Exposure can exceed 100 times the NIOSH recommended exposure limit.
In evaluations of engineering controls, Meeker et al. and Yasui et al. respectively observed 93 and 98 percent reductions in respirable silica, compared to use of no control, during the use of a Metabo grinder with an ICS Dust Director shroud and vacuum.
Effects on Productivity:
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.
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.
Hazards Addressed:
- Paints & Coatings
- Perform abrasive blasting
- Prepare surfaces with mechanical devices
Availability
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
Dustless Technologies CutBuddie Dust Director
To obtain information, visit http://www.dustlesstools.com
or contact 1-800-568-3949
Bosch 5-inch Tuckpoint Grinder with Dust Extraction Port and AirSweep Vacuum
To obtain information, visit http://www.boschtools.com
or contact 1-877-262-2499
Pullman-Ermator dust extractors and pre-separators
To obtain information, visit http://www.pullman-ermator.se
or contact 1-800-232-2635 info@pullman-ermator.com
Blastrac 5-inch Tuc-Pointer and vacuums
To obtain information, visit http://www.blastrac.com
or contact 1-800-256-3440
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
CS Unitec/FLEX F1509FRD 5-inch Tuck-Pointing Machine and vacuums
contact 1-800-700-5919 info@csunitec.com