Production > Table Saws
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Table saws are used for straight sawing. Depending
on the blade, they cut either across (crosscut) or with (ripsaw) the grain
of the wood.
Operator Involvement
With the hand-fed saws, the operator adjusts the height
and angle of the blade. Then, holding the stock, the operator pushes it
into the blade. A guide is used to maintain a straight cut at the desired
width. At the end of the cutting stroke, the operator either changes
positions or pushes the stock past the blade. Self-feed or power table saws are equipped with rollers or a conveyor system to hold the lumber and
force-feed it into the saw blade.
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Potential Hazard:
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Point of operation - Injuries can occur if an operator's hands slip as he or
she is feeding the stock into the saw or if the operator holds his or her
hands too close to the blades while cutting. The operator can also be injured
when removing scrap or finished pieces from the table.
Possible Solutions:
Engineering Controls
- Ripsaws and crosscut saws. Enclose the portion of
the saw above the table with a self-adjusting guard
(Fig. 1). The guard must adjust to the thickness of
the material being cut and remain in contact with it
[29
CFR 1910.213 (c)(1) and
(d)(1)]. Hinge the guard
so that the blades can be easily changed.
- Attach a brake to the motor's arbor to stop the
saw from coasting after it has been cut off, or have
the operator remain at the saw station once the
motor is shut off until the blade stops turning.
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Fig 1 - Saw blade with
a Self-Adjusting Guard.
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Work Practices
- Keep hands out of the line of the cut.
- Use a push stick for small pieces of wood and for
pushing stock past the blade. [29
CFR 1910.213(s)(9)].
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Potential Hazard:
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Other moving parts - Contact with the blade under the
table, or with the power transmission apparatus (if not
enclosed), may occur.
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Possible Solution:
Engineering Controls
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Always guard the portion of the blade below the
table. Operators must be protected from possible
contact when reaching under the table [29
CFR 1910.213(a)(12)].
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Potential Hazard:
- Kickbacks (that is,
when the blade catches the stock and throws it back toward the operator)
are another major cause of injury. Kickbacks can result if the blade
height is not correct or if the blade is not properly maintained.
Kickbacks are more likely to occur when ripping, rather than crosscutting.
Kickbacks also can occur if safe-guards are not used or if poor-quality
lumber is cut.
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Possible Solutions:
Engineering Controls
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For ripsaws, use a spreader to prevent material
from squeezing the saw or kicking back during
ripping [29
CFR 1910.213(c)(2)]. Use anti-kickback
fingers to hold the stock down in the event that the
saw kicks back the material [29
CFR 1910.213(c)(3)].
Work Practices
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Use proper blade for cutting action (for example,
don't use crosscut blade for ripping).
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Operate saw at speed specified by the
manufacturer.
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Maintain and sharpen blade [29
CFR 1910.213(s)(2)].
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Leave sufficient clearance for stock.
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Stand to side of the saw blade to avoid injury due
to kickback.
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Guide stock parallel to the rip fence to minimize
the potential for kickback.
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Avoid crosscutting long boards on table saws.
Considerable hand pressure is required close to the
saw blade, and the boards create a safety hazard to
other people.
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Use a filler piece between the fence and the saw
blade when necessary (e.g., when there is little
clearance on the fence side).
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Properly support all pieces of stock, including
the cut and uncut ends, scrap, and finished product.
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Potential Hazard:
- Flying particles - Wood chips, splinters, and broken
saw teeth may be thrown by the cutting action of the
blade.
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Possible Solution:
Work Practices
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