Solution Summary: Jackhammer Shroud and Vacuum Dust Control
Description:
Breaking or chipping concrete with jackhammers, also known as pavement breakers, generates a large amount of dust which may contain high levels of crystalline silica and creates a hazard for everyone in the vicinity. Vacuum dust controls exist for portable jackhammers and pavement breakers. 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 fits over and partially encloses the bit, or tool. The vacuum draws air and dust from the bit, the point of dust generation, into the shroud where it is transported through tubing and into the vacuum's bag or reservoir.
Environmental Safety Solutions, LLC Enviroboot EB-1
- Designed to fit most large electric jackhammers or demolition hammers, including Bosch Brute, Hitachi, Wacker and Makita. Custom adaptors are available for other brands.
- Weight: 2 pounds
- Length: 15 inches
- Diameter: 6 inches at the top hose clamp
- Vacuum take-off diameter: 2 inches
(Photo courtesy of Environmental Safety Solutions)
- 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**
|
Horse
power
|
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 |
(Photo courtesy of Husqvarna AB Construction Division)
- 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 |
(Photo courtesy of Husqvarna AB Construction Division)
- 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
|
Inlet Diameter, inches
|
Weight, pounds
|
C3000 | 2 | 49 |
C5500 | 3 | 130 |
(Photo courtesy of Husqvarna AB Construction Division)
(Photo courtesy of Husqvarna AB Construction Division)
Risks Addressed:
How Risks are Reduced:
The shrouds partially enclose the jackhammer bit 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 bit, capturing dust and silica near 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 still be required.
In evaluations of engineering controls, Echt et al. observed a 59 percent reduction in respirable dust, compared to no control, during the use of a jackhammer with an Atlas Copco rock-drill shroud and dust extractor. While exposures to respirable dust during use of the local exhaust ventilation system were below the occupational exposure limits, they are likely to have approached or exceeded OSHA Permissible Exposure Limits (PELs), NIOSH Recommended Exposure Limits (RELs) and ACGIH Threshold Limit Values (TLVs) for respirable silica, given the percent silica in bulk samples of the work materials. In spite of reductions in respirable dust exposure while using local exhaust ventilation, a respirator may still be necessary to reduce silica exposures to less than the REL and TLV when breaking concrete with a jackhammer.
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 breaking concrete.
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.
Availability
Pullman-Ermator, Inc.
To obtain information, visit single phase electric dust extractors and three phase electric dust extractors and c-line pre seperators
or contact 1-855-736-2869 hcpcustomer.service@husqvarna.com
Environmental Safety Solutions, LLC Enviroboot EB-1
To obtain information, visit Enviroboot EB-1
or contact 1-212-922-9001 sales@enviroboot.com