• Amputations are among the most severe and disabling workplace
  injuries
• Amputations may result from improperly using machines
• In 2005, 8,450 non-fatal amputations occurred within the private
  industry sector
• In 2008, machines were the primary or secondary source of 604
  work-related fatalities (BLS, 2010b)
• That same year, machinery was the source of 64,170 cases
  involving days away from work (BLS, 2010b)
• Protect yourself from amputations and other hazards by using
  effective machine guarding
• Machine-related injuries may include
  – Crushed hands and arms
  – Severed fingers and limbs
  – Lacerations and abrasions
• Moving machine parts create many hazards
  – Pinch points
  – Rotating parts
  – Flying chips
  – Sparks

• Guards are barriers which prevent access to danger areas
  – Act as physical barriers
  – Enclose and prevent employee contact with dangerous machine parts
• Machine guards are essential for protecting you from preventable injuries

All machines consist of three areas

• Point of operation
  – Where work is performed on the material
  – Work may include cutting, shaping, boring, or forming of stock
• Power transmission device
  – All components of the machine that transmit energy to the part of the
  machine performing work
  – Include flywheels, pulleys, belts, connecting rods, couplings, cams,
     spindles, chains, cranks, and gears
• Other moving parts
  – All parts of the machine that move while the machine is energized
  – May include reciprocating, rotating, and transversely moving parts, as
     well as feed mechanisms

• Rotating motion
  – Circular motion
  – Generated by rotating collars, couplers, cams, clutches, flywheels,
     shaft ends, and spindles
  – May grip clothing or force a body part into a dangerous location
• Reciprocating motion
  – Back-and-forth or up-and-down motion
  – May strike or entrap an employee between a moving part and a
     fixed object
• Transverse motion
  – Motion in a straight, continuous line
  – May strike or catch employee in a pinch or shear point

• Cutting action
  – Involves rotating, reciprocating, or transverse motion
  – Seen in band saws, circular saws, boring or drilling machines, turning           machines, or milling machines
• Punching action
  – Results when a slide or ram hits a fixed object
  – Seen in power presses and ironworkers
• Shearing action
  – A slide or knife trims metal or other materials
  – Seen in mechanical, hydraulic, or pneumatic shears
• Bending action
  – A slide draws or stamps metal
  – Seen in power presses, press brakes, and tubing benders

• Prevent contact
  – Must prevent hands, arms, or any other part from making contact with
     dangerous moving parts
• Secure
  – Guard should not be easily removed
• Protect from falling objects
  – Should ensure that no objects can fall into moving parts or strike worker
• Create no new hazards
  – Guard should not present new hazards
• Create no interference
  – Should not impede worker from performing job
• Allow safe lubrication
  – Should be able to lubricate machine without removing guard

• Fixed
• Interlocked
• Adjustable
• Self-adjusting

• Characteristics
  – Permanent part of the machine
  – May be constructed of sheet metal, screen, wire
     cloth, bars, or plastic
• Safeguarding action
  – Provides a barrier
  – Allows for stock feeding but does not permit
     operator to reach danger area

• Characteristics
  – Guard opens and closes to admit stock
• Safeguarding action
  – Provides a barrier that moves according to
     the size of the stock entering the danger area

There are two types of safeguarding methods

• Primary safeguarding methods
  – Guards
  – Some type of safeguarding device
• Secondary safeguarding methods
  – Probe detection and safety edge devices
  – Awareness devices

Safeguarding devices are primary safeguarding
methods that detect or prevent inadvertent access
to a hazard

• Prevent machine operation if your hand or body
  part is placed in the danger area
• Restrain or withdraw your hands from the danger
  area
• Require you to place both hands on machine
  controls

Primary safeguards include

• Pullback devices
  – A series of cables are attached to the operator’s hands,
     wrists, or arms
  – As the machine begins to cycle, the operator’s hands are
     pulled out of the danger area
• Restraint devices
  – Cables are attached to operator
  – Prevents operator from reaching into the danger area
  – Operator must use hand-feeding tools
• Presence-sensing mats
  – Senses operator is near danger area and shuts
     off machine
• Two-hand control
  – Requires operator to use both hands on
     separate controls
  – Prevents hands from being in the danger area
     when machine cycle states

• Two-hand trip
  – Requires concurrent use of both hands
  – Prevents hands from being in danger area
     when machine starts
• Gates
  – Movable barrier that protects the operator
     at the point of operation

• Exposed fan blades must be guarded by a
  barrier with openings no larger than ½ inch
• Interlock revolving barrels, containers, and
  drums
• Securely anchor fixed machines to prevent
  walking or moving
• Use Lockout/Tagout

 

• Operators should receive specific and detailed
  training in safeguarding against mechanical hazards
• Operator training should explain
  – The hazards associated with particular machines
  – How and why to use each safeguard
  – How and under what circumstances safeguards can be removed
  – When lockout/tagout is required
  – What to do if a safeguard is damaged, missing, or inadequate

When performing machine repair and maintenance,
each piece of equipment should be safeguarded

• Notify all affected employees that the machine or equipment
  must be shut down to perform maintenance or repairs
• Stop the machine
• Isolate the machine or piece of equipment from its energy
  source
• Lockout or tag out the energy source
• Relieve any stored or residual energy
• Verify that the machine or equipment is isolated from the
  energy source

When machine maintenance and repairs are finished, the
following steps should be followed to put the machine back in
service

• Inspect the machine to ensure that all guards and safety devices are in place and functional
• Check to ensure that start up of the machine will not endanger employees
• Remove lockout/tagout devices
• Reenergize the machine
• Notify all affected employees that the machine is back up and running

• Appropriate PPE provides the last line of defense in machine guarding
• Appropriate PPE may include
  – Hard hats
  – Face shields, safety goggles, or glasses
  – Hearing protection
  – Protective coveralls, jackets, vests, aprons, or full-body suits
  – Special sleeves and gloves
  – Safety shoes and boots