Solution Summary: Downdraft Tables for Woodworking
Description:
A downdraft table is an engineering control that can reduce exposure to wood dust. Downdraft tables are workbenches with slots or holes in the horizontal work surface. Air is drawn past the workpiece and into the slots or holes by a vacuum, which is either attached via the extraction port or built into the table, capturing dust near the point of generation. The wood dust is then collected and removed from the work environment, reducing the concentration in the worker's breathing zone and the opportunity for skin contact.
- Cost: $6,800 (verified 5/2011)
- Work Surface Dimensions: 36 x 48 inches
- Work Surface Height: 34 inches
- Airflow Rate: 2,400 cubic feet per minute
- Power Requirements: 120/240 volts, 24/12 amps (single phase); 230/480 volts, 6.8/3.4 amps (3 phase)
- Weight: 300 pounds
- Filtration Efficiency: 3 filters rated to remove 80% of 9.0 micron particles followed by 2 filters rated to remove 99.99% of 0.5 micron particles. HEPA filter is optional
- Automatic Pulse-Jet filter cleaning
- Differential pressure gauge, which can be used to monitor air flow
- Sound Pressure Level: 75 dBA at 5 feet (OSHA’s Permissible Exposure Limit for an 8-hour time-weighted average is 90 dBA)
The Denray Model 2872 downdraft table uses a tube filtration system. (Photo courtesy of Denray Machine Inc.)
- Cost: $3,200 – 3,300 (verified 4/2011)
- Work Surface Dimensions: 28 x 72 inches
- Work Surface Height: 34.5 inches
- Airflow Rate: 3,400 cubic feet per minute
- Power Requirements: 120/220 volts, 18/9 amps (single phase), 230/460 volts, 6.5/2.8 amps (3 phase)
- Weight: 490 pounds
- Filter Efficiency: 99% at 1 micron, optional HEPA filter is capable of removing 99.97% of 0.3 micron particles (the most penetrating size)
- Sound Pressure Level: 77 dBA (OSHA’s Permissible Exposure Limit for an 8-hour time-weighted average is 90 dBA)
A flat top downdraft table by Dual Draw. (Photo courtesy of Dual Draw)
- Filter Efficiency: 95% for 0.7 micron particles, optional HEPA filter is capable of removing 99.97% of 0.3 micron particles (the most penetrating size)
- Work Surface Height: 34 inches
- Sound Pressure Level: 70 to 78 dBA (OSHA’s Permissible Exposure Limit for an 8-hour time-weighted average is 90 dBA)
Model
|
Work Surface Dimensions (inches)
|
Airflow Rate (cubic feet per minute)
|
FT3036
|
30 x 36
|
2,000
|
FT3048
|
30 x 48
|
2,500
|
FT3060
|
30 x 60
|
2,500
|
FT3060A
|
30 x 60
|
4,000
|
FT3072
|
30 x 72
|
2,500
|
FT3072A | 30 x 72 | 4,500 |
FT3096 | 30 x 96 | 5,000 |
In addition to flat top models, please visit the manufacturer for other types of downdraft tables.
Risks Addressed:
Exposure to wood dust in the workplace has several associated hazards. Wood dust irritates the eyes, nose and throat, in addition leads to pulmonary function impairment. Western red cedar dust is considered a human carcinogen and has also been shown to cause asthma. Significant accumulation of fine wood dust particles can also be a fire and explosion hazard in the workplace.
How Risks are Reduced:
Downdraft tables are workbenches with slots or holes in the horizontal work surface. Air is drawn past the workpiece and into the slots or holes by a vacuum, which is either attached via the extraction port or built into the table, capturing dust near the point of generation. The wood dust is then collected and removed from the work environment, reducing the concentration in the worker's breathing zone and the opportunity for skin contact.
Effects on Productivity:
Vacuum dust collectors should have a positive effect on productivity and definitely improve the quality of the work by removing large amounts of dust, which provides a cleaner environment for operators and reduces the effort and time required for clean-up. In some cases, particularly where work is intermittent or in an area with general ventilation, use of dust collectors may be adequate to reduce the need to wear a respirator, and the need for an employer’s respiratory protection program.
Additional Considerations:
- Keeping your head away from dust created by the process and using adequate ventilation is key to controlling exposure to airborne dust particles.
- The Scientific Committee on Occupational Exposure Limits (SCOEL), which was established by the European Commission, stated that exposures greater than 0.5 mg/m3 of wood dust could cause pulmonary effects and should be avoided.
- The particles that can do the most damage in the lungs are small enough to penetrate or bypass 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.
- 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 and coarse pre-filters are available with some vacuums and may help maintain the air flow rate.
As is the case with any construction equipment, users should follow manufacturer scheduled maintenance and safety recommendations and comply with any applicable regulations.
Availability
JET 708403K Downdraft Table
To obtain information, visit http://www.jettools.com
or contact 1-800-274-6848 customerservice.us@waltermeier.com
Denray Downdraft Table
To obtain information, visit http://www.denray.com/
or contact 1-800-766-8263 sales@denray.com
DualDraw Downdraft Tables
To obtain information, visit http://www.dualdraw.com
or contact 1-800-977-2125 service@dualdraw.com
Filter 1 Downtron DFW Series
To obtain information, visit http://filter-1.com
or contact 1-800-289-0189 info@filter-1.com
Air Dynamics Air Wolf Downdraft Table
To obtain information, visit https://www.airdynamics.net/
or contact 1-717-854-4050 sales@airdynamics.net