Subpart O Machine Guarding

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Subpart OMachine Guarding
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Subpart O

• 1910.211 Definitions
• 1910.212 General Requirements for all Machines
• 1910.213 Woodworking Machinery
• 1910.215 Abrasive Wheel Machinery
• 1910.216 Mills and Calendars
• 1910.217 Mechanical Power Presses
• 1910.218 Forging Machinery
• 1910.219 Mechanical Power-Transmission

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Basics of machine safeguarding

• A good rule to remember is
• Any machine part function or process which may
  cause injury must be safeguarded.

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Basic areas of safeguarding

• The point of operation
• Power transmission apparatus
• Other moving parts (reciprocating, transverse,
  or rotating)

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Motions

• Rotating (including in-running nip points)
• Reciprocating
• Transverse

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Nip points
7
In running nip points on rolls
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Nip points
9
Rotating hazards
Burr
Rotating shaft and pulleys with projecting key
and set screw
Rotating pulley with spokes and projecting burr
on face of pulley
Rotating coupling with projecting bolt heads
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Pinch points caused by tables
Table
Bed (stationary)
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Guarding table pinch points
12
Transverse motion of a belt
Transverse motion of belt
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Safeguarding

• Guards
• Prevent access to the danger areas
• Devices
• Control access to the point of operation

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Actions

• Cutting
• Punching
• Shearing
• Bending

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Different actions
Stock
Cutting tool
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Guards

• Fixed
• Interlocked
• Adjustable
• Self-adjusting

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Fixed guard on a bandsaw
Wheel guard
Blade guard
Wheel guard
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Fixed guard on a power press
Stock entering danger zone
Stock exit
Transparent insert in front panel
19
Fixed guard enclosing belt and pulleys
Inspection panel
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Fixed guard on veneer clipping
Guard
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Fixed guard on a power squaring shear
Blade guard
Throat and gap guard
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Ends and unused portion of press brake guarded

• Power press brake (When used in a power press)
• The requirements of 41231-5-10
• Shall be applicable to power press brakes when
  used for other than bending operations

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Adjustable guard on horizontal bandsaw
Adjustment knob
Guard
Blade
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Adjustable guard on power press
Adjustable bars
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Pedestal grinder
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Portable grinders
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Adjustable guard on bandsaw
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Adjustable guard on table saw
Crank for height adjustment
Handle for extending or retracting guard over
blade
Saw blade
Guard
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Adjustable guard on wood shaper
Nut for height adjustment
Guard
Base of shaper blade
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Adjustable guard on router
Adjustment nuts
Guard
Stock
Base of router blade
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Self-adjusting guard on radial arm saw
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Self-adjusting guard on circular saw
Guard retracted
Stock
Blade
Guard
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Self-adjusting guard table saw
First guard
Second guard
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Self-adjusting guard on jointer
Guard in rest position
Guard
Stock
35
Awareness barrier on back side of shear
Awareness barrier
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Awareness barrier on stitching machine
Awareness barrier
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Shields on a drill press and lathe
Transparent shield
Lathe
Drill
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Devices

• Presence sensing
• Photo-electrical
• Radio-frequency
• Electromechanical
• Pullback
• Restraint

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Photoelectric presence sensing devices
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Photoelectric presence sensing devices cont
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Photoelectric presence sensing device on press
brake
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Radio-frequency presence sensing device on press
Antenna
Capacitance field
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Electromechanical sensing device on an eye-letter

• Similar safety devices are utilized on spot
  welders and riveters

Probe in contact with fingers, machine will not
cycle
Air-operated welder
Rocker-arm welder
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Pullback device on A power press
Pullback mechanism
Danger area
Wristband
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Pullback device on A press brake
Nylon pullback straps are attached to wristbands
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Restraint device on A power press
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Devices

• Safety controls
• Safety trip control
• Pressure-sensitive body bar
• Safety triprod
• Safety tripwire cable
• Two-hand control
• Two-hand trip

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Pressure-sensitive body bar on rubber mill
Bar
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Safety triprod on a rubber mill
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Safety tripwire cable on A calender
Cable
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Two-hand control buttons on a part-revolution
clutch power press
Control buttons
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Two-hand trip buttons on afull-revolution clutch
power press
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Devices

• Gates
• Interlocked
• Other
• Location/distance

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Horizontal injection molding machine with gate
guards
Gate
Handle
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Power press with gate guards
Gate
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Robot with fixed barrier guards
Press
Robot
Stock conveyor
Fixed barrier
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Robot danger areas
Danger area
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Potential feeding and ejection methods to improve
safety for the operator

• Automatic feed
• Semi-automatic feed
• Automatic ejection
• Semi-automatic ejection

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Power press with automatic feed
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Power press with chute feed
Chute inclined as necessary for gravity feeding
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Power press with sliding die
Handle
Die stop
Die slide
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Power press with sliding bolster
Bolster in retracted position
Die in stock placement or removal
position(bolster in extended position)
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Saw with auto indexing mechanism and traveling
head
Blade enclosure guards
Indexing mechanism
Stock
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Holding tools
Pliers with curved handles for two-handed usage
Duckbill pliers
Right angle jaw tongs for handling flanged or cup
shaped work pieces
Feeding tongs
A lightweight tweeter made of steel springs
Vacuum-tongs for feeding positioning heavy formed
parts
Magnetic lifter twist-off
Double magnet withrelease lever
Tong device used to tube or cup
Double cup lifterwith release button
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Pushing devices
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Five concerns on any machine

• Safeguarding - guard, device, method
• Controls - control reliability
• Disconnect - lockable in off position
• Starter - magnetic (for drop-out protection)
• Covers - rotating components covered to 7ft. from
  floor or from working platform.

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Safety blocks installed on power presses
Safety block
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Lockout devices required for all machines