Osha 10 Hour Construction Hand and Portable Power Tools

 
parts, and
 
flying 
chips and sparks
Safety guards must never be removed when a tool is being used. 
Hand and Portable Power Tools 
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OSHA 10 Hour Construction 
For example, portable 
circular saws must be 
equipped with guards. An 
upper guard must cover 
the entire blade of the 
saw. A retractable lower 
guard must cover the 
teeth of the saw, except when it makes contact with the work 
material. The lower guard must automatically return to the covering 
position when the tool is withdrawn from the work.
Safety Switches
The following hand-held powered tools must be equipped with a 
momentary contact "on-off' control switch: drills, tappers, fastener 
drivers, horizontal, vertical and angle grinders with wheels larger 
than 2 inches in diameter, disc and belt sanders, reciprocating 
saws, saber saws, and other similar tools. These tools also may be 
equipped with a lock-on control provided that a single motion of the 
same finger or fingers that turn it on can accomplish turnoff.
The following hand-held powered tools may be equipped with only 
a positive "on-off' control switch: platen sanders, disc sanders with 
discs 2 inches or less in diameter; grinders with wheels 2 inches or 
less in diameter; routers, planers, laminate trimmers, nibblers, 
shears, scroll saws and jigsaws with blade shanks 1 ¼” wide or 
less.
Other hand-held powered tools such as circular saws having a 
blade diameter greater than 2 inches, chain saws, and percussion 
tools without positive accessory holding means must be equipped 
with a constant pressure switch that will shut off the power when 
the pressure is released.
Electric Tools
Employees using electric tools must be aware of several dangers; 
the most serious is the possibility of electrocution.
Among the chief hazards of electric- powered tools are bums and 
slight - shocks which can lead to injuries or even heart failure. 
Under certain conditions, even a small amount of current can result 
in fibrillation of the heart and eventual death. A shock also can 
cause the user to falloff a ladder or other elevated work surface.
To protect the user from shock, tools must either have a three-wire 
cord with ground and be grounded, be double insulated, or be 
powered by a low-voltage isolation transformer. Three-wire cords 
Hand and Portable Power Tools 
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OSHA 10 Hour Construction 
contain two current-carrying conductors and a grounding conductor. 
One end of the grounding conductor connects to the tool's metal 
housing. The other end is grounded through a prong on the plug.. 
Anytime an adapter is used to accommodate a two-hole receptacle, 
the adapter wire must be attached to a known ground. The third 
prong should never be removed from the plug.
Double insulation is more convenient. The user and the tools are 
protected in two ways: by normal insulation on the wires inside, and 
by a housing that cannot conduct electricity to the operator in the 
event of a malfunction.
These general practices should be followed when using electric 
tools:
•
Electric tools should be operated within their design limitations.
•
Gloves and safety footwear are recommended during use of 
electric in case of breakage.
•
When not in use, tools should be stored in a dry place. 
•
Electric tools should not be used in damp or wet locations. 
•
Work areas should be well lighted