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  • 1910.212(a)(1) Types of guarding. One or more methods of machine guarding shall be provided to protect the operator and other employees in the machine area from hazards such as those created by point of operation, ingoing nip points, rotating parts, flying chips and sparks. Examples of guarding methods are-barrier guards, two-hand tripping devices,electronic safety devices, etc. 1910.212(a) Machine guarding. 1910.212(a)(1) Types of guarding. One or more methods of machine guarding shall be provided to protect the operator and other employees in the machine area from hazards such as those created by point of operation, ingoing nip points, rotating parts, flying chips and sparks. Examples of guarding methods are-barrier guards, two-hand tripping devices,electronic safety devices, etc. 1910.212(a)(2) General requirements for machine guards. Guards shall be affixed to the machine where possible and secured elsewhere if for any reason attachment to the machine is not possible. The guard shall be such that it does not offer an accident hazard in itself. 1910.212(a)(3) Point of operation guarding. 1910.212(a)(3)(i) Point of operation is the area on a machine where work is actually performed upon the material being processed. ..1910.212(a)(3)(ii) 1910.212(a)(3)(ii) The point of operation of machines whose operation exposes an employee to injury, shall be guarded. The guarding device shall be in conformity with any appropriate standards therefor, or, in the absence of applicable specific standards, shall be so designed and constructed as to prevent the operator from having any part of his body in the danger zone during the operating cycle. 1910.215(b)(9) Exposure adjustment. Safety guards of the types described in Subparagraphs (3) and (4) of this paragraph, where the operator stands in front of the opening, shall be constructed so that the peripheral protecting member can be adjusted to the constantly decreasing diameter of the wheel. The maximum angular exposure above the horizontal plane of the wheel spindle as specified in paragraphs (b)(3) and (4) of this section shall never be exceeded, and the distance between the wheel periphery and the adjustable tongue or the end of the peripheral member at the top shall never exceed one-fourth inch. (See Figures O-18, O-19, O-20, O-21, O-22, and O-23.) 1910.215(a)(4) Work rests. On offhand grinding machines, work rests shall be used to support the work. They shall be of rigid construction and designed to be adjustable to compensate for wheel wear. Work rests shall be kept adjusted closely to the wheel with a maximum opening of one-eighth inch to prevent the work from being jammed between the wheel and the rest, which may cause wheel breakage. The work rest shall be securely clamped after each adjustment. The adjustment shall not be made with the wheel in motion 1910.219(d)(1) Guarding. Pulleys, any parts of which are seven (7) feet or less from the floor or working platform, shall be guarded in accordance with the standards specified in paragraphs (m) and (o) of this section. Pulleys serving as balance wheels (e.g., punch presses) on which the point of contact between belt and pulley is more than six feet six inches (6 ft. 6 in.) from the floor or platform may be guarded with a disk covering the spokes. 1910.219(e)(3)(i) Vertical and inclined belts shall be enclosed by a guard conforming to standards in paragraphs (m) and (o) of this section. 1910.219(f)(3) Sprockets and chains. All sprocket wheels and chains shall be enclosed unless they are more than seven (7) feet above the floor or platform. Where the drive extends over other machine or working areas, protection against falling shall be provided. This subparagraph does not apply to manually operated sprockets. 1910.213(h)(1) The upper hood shall completely enclose the upper portion of the blade down to a point that will include the end of the saw arbor. The upper hood shall be constructed in such a manner and of such material that it will protect the operator from flying splinters, broken saw teeth, etc., and will deflect sawdust away from the operator. The sides of the lower exposed portion of the blade shall be guarded to the full diameter of the blade by a device that will automatically adjust itself to the thickness of the stock and remain in contact with stock being cut to give maximum protection possible for the operation being performed. 1910.217(e)(1)(i) It shall be the responsibility of the employer to establish and follow a program of periodic and regular inspections of his power presses to ensure that all their parts, auxiliary equipment, and safeguards are in a safe operating condition and adjustment. The employer shall maintain a certification record of inspections which includes the date of inspection, the signature of the person who performed the inspection and the serial number, or other identifier, of the power press that was inspected. 910.219(e)(1)(i) Where both runs of horizontal belts are seven (7) feet or less from the floor level, the guard shall extend to at least fifteen (15) inches above the belt or to a standard height, except that where both runs of a horizontal belt are 42 inches or less from the floor, the belt shall be fully enclosed in accordance with paragraphs (m) and (o) of this section.

Gi2011machineguard Gi2011machineguard Presentation Transcript

  • Machine Guarding Draft 5 2 11
  • Pre-Industrial revolution
    • Waterwheel was source of injuries
    • Injuries taken as matter of course since infrequent
    • Regarded as victim’s own fault
  • Industrial Revolution
    • Steam engine and electric motors invented
    • Increased use of power driven machinery
    • Workers caught by projecting set screws on line shafting
    • Crushed flat by belts and pulleys
    • Chewed inch by inch in gears and screw conveyors
  • Public Reaction
    • Workers felt unguarded machines partly employers fault
    • Newspapers printed details of gory cases
    • Labor unions fought for guarding of hazardous machinery
  • Massachusetts 1877
    • First law requiring guarding of hazardous machinery
    • Outrage over young girls getting fingers cut off or mangled in adjacent gears of textile machines
    • By 1900 most industrialized states had laws requiring machine guarding
  • Massachusetts Study 1939
    • Studied injuries from 1933-1938
    • Woodworking machines highest source of all machine injuries with 18.5%
    • Saws 53% of those injuries (circular saws #1)
  • 1949 Illinois
    • 4,908 injuries due to machines requiring worker compensation in manufacturing or 21.7 % of total
    • Little attention placed on safe placing of machines, emergency stops, and safe arrangement of machine controls
  • Safety Codes
    • Safety Code for Mechanical Power Transmission Apparatus published in the 1940’s by American Standards Association
    • Very similar to OSHA 1910.219 std.
    • Required forethought guarding vs. afterthought guarding for machine manufacturers
  • Machine Hazards
    • Motions Rotating: in-running nip points, spindles, shaft ends, couplings Reciprocating: back-and-forth, up-and-down Transverse: movement in a straight, continuous line
    • Operations Cutting: bandsaws, drills, milling machines, lathes Punching: punch presses, notchers Shearing: mechanical, pneumatic, or hydraulic shears Bending: press brakes, tube benders, plate rolls
  • Principles of Machine Guarding
    • Safe Distance - 7’ rule of belts, etc.
    • Guards - employees can’t get in hazardous area through the use of barriers.
    • Table 0-10 for guard opening design
    • Devices - Presence sensing mats, pullbacks, light curtains, restrains
  • Table O-10
    • Distance of opening from the point of operation hazard (in inches)
    • 1/2 to 1 1/2
    • 1 1/2 to 2 1/2
    • 2 1/2 to 3 ½
    • 3 1/2 to 5 ½
    • 5 1/2 to 6 ½
    • 6 1/2 to 7 ½
    • 7 1/2 to 12 ½
    • 12 1/2 to 15 ½
    • 15 1/2 to 17 ½
    • 17 1/2 to 31 ½
    • Maximum width of opening (in inches)
    • ¼
    • 3/8
    • ½
    • 5/8
    • ¾
    • 7/8
    • 1 ¼
    • 1 ½
    • 1 7/8
    • 2 1/8
  • Types of Machine Safeguards
    • Barriers and guards
    • Mechanical or electronic devices that restrict contact, such as presence-sensing, restraining, or tripping devices, two-hand controls, or gates.
    • Feeding and ejection methods that eliminate part handling in the hazard zone.
  • Definitions
    • Point of Operation - work such as bending, punching, cutting on the material – P.O.O
    • Nip point - location where machine pieces come together such as belts and a pulley, two in-running rollers, etc.
    • $140,00
    • Unguarded mandrel winder carriage
    • Unguarded rotating shaft amputated worker arm when sleeve caught on a collar bolt
    Wire or filament is wound around a rotating mandrel.
  • Guarding Most Cited
    • Unguarded nip points, rotating parts
    • No P.O.O. Guarding
    • Tongue grinder ¼”
    • Work Rest 1/8”
    • Unguarded pulleys
    • Unguarded Vertical Belts
    • Chain and sprocket not guarded
    • Lower blade guard radial arm saw
    • No punch press inspection records
    • Unguarded horizontal belts
  • Shafts
    • Hazard - caught in
    • Unguarded rotating shafts can easily snagged clothing or hair
    • Fixed Guards used
  • In-running Nip Points
    • Belts and Pulleys
    • Chains and Sprockets
    • Gears
    • In-running rollers
    • Fixed Guards used the most
    • CSHO will review OSHA 200 and 300 logs for all amputation injuries or hazards
    • Limited to hazards associated with power presses, press brakes, saws, shears, slitters, and slicers, but may be expanded
    • Inspections began March 26, 2002
    • CPL 2-1.35
  • AMPUTATE LEP cont.
    • CSHO will also evaluate employee exposures during the following:
      • Regular operation of machine
      • Setup/threading/preparation for operation of machine
      • Clearing jamups or upset conditions
      • Making adjustments while machine is operating
      • Cleaning of machine
      • Oiling/greasing of machine /machine parts
      • Scheduled/unscheduled maintenance
      • Lockout/tagout considerations
  • Punch Presses
    • Point of Operation guarding required on front, back, sides
    • Prevent Double trips - double trip took both hands of a worker in 1997
    • Inspection, records, employee training
  • Horizontal Molding Presses
    • Hazard is getting caught in horizontal ram
    • Interlocked doors used
    • Lockout for repairs
  • Press Brakes
    • Employee reaches in to get stuck material
    • Pullbacks, light curtains
    • 12 inches safe distance per ANSI
    • Opening too large
    • 1984 - Eight fingers lost on hydraulic brake in IL
  • Shears
    • Most come with guards
    • Table O-10 distance must be used
    • Guards bent back on this shear
  • Slicers
    • Commonly used to slice meat and food
    • Use rotary blade
    • Guillotine cutters used in other industries
    • Most injuries occur in restaurants and grocery stores
  • Circular Saws
    • Lower blade guard required
    • Clean saw and blade to prevent guard from sticking
    • Aurora 1998 - 100+ stitches from saw
  • Vertical Bandsaw
    • Adjustable guard to height of product
    • Many injuries by guiding product into POO
    • Handling cold slippery products will increase chances of slipping into POO
  • Horizontal Bandsaw
    • Unused portion of blade need to be guarded
    • No oversized blades used
  • Radial Arm Saw
    • Lower blade awareness device
    • Retracts to original position
    • Does not extend past plane of table
    • Anti-kick back device
  • Table Saws
    • Top guard
    • Magnetic restart
    • Spreader
    • Push sticks
    • Anti-kick device
  • Chop Saw
    • Lower blade awareness device
    • Speed marked on saw
    • Clean saw blades to prevent varnish/sap buildup
  • Food Mixers
    • Requires cleaning of food
    • Rotating blades
    • Hand Amputation in 2002
  • Conveyors
    • Emergency stops placed
    • ANSI B20.1
    • In-running nip points guarded by fixed guards
    • This elevator section unguarded
  • Calendars and Rubber Mills
    • Emergency trips placed so operator breaks emergency stop cable
    • Less than a second to get pulled in
  • Take-up Coils/Reels
    • Often slow moving
    • Several amputations due getting caught in nip point
    • Interlock guards or barriers used
    • Unguarded fabrictake-up roll nip point
  • Fans
    • Hazard - rotating blades
    • Use wire mesh guard
  • Printing Press
    • Fixed guard prevent entry to moving nip point when cleaning rolls
    • Interlocked Guards for ink addition
  • Packaging Machines
    • Multiple pinch points
    • Employee reach in to clear jams
    • Fixed guards or light curtains
    • Lockout is needed
    • 1999 - Aurora amputation
  • Drill Press
    • Hair or clothing get caught in rotating shaft
    • Automatic ones can guard against pinch point via 1/4 opening or presence sensing devices
  • Belt Sanders
    • Hazard is nip point
    • Use fixed guard
  • Bench Grinders
    • Tongue Guard - 1/4”
    • Work rest - 1/8”
    • Blotters used
    • Ring test
    • Spindle speed
    • Side nut guarded
  • Surface Grinder
    • Half moon guard over wheel
    • No feeding by hand
    • Proper wheel speed
  • Lathes
    • Eye protection glasses with side-shields.
    • Use Guard over chuck
    • No loose sleeves, long hair, or jewelry
    • Work is securely clamped in the chuck. Start the lathe at low speed and increase the speed gradually.
    • Removing the chuck key immediately after use.
  • Mixer/Blenders
    • Fixed guard needed
    • Worker reaches in to clean or clear jam and it restarts
    • Must lockout
    • 1995 - arm amputation was $1M loss
  • Auctioned or Used Machines
    • Often missing guards
    • Employer must guard even if not designed with them
    • Consult ANSI standard applicable
  • Training
    • A description and identification of the hazards associated with the machine(s).
    • A description of the safeguards and their functions and use.
    • Instruction on how, and under what circumstances safeguards may be removed, and by whom.
    • Instruction on what to do if a safeguard is missing, damaged, or inadequate
  • Summary
    • If a four year could get hurt with a machine, an adult will eventually get hurt too.
  • Quiz
    • Tongues on grinders must be adjusted to ____ inches from the wheel.
    • List the guards required on a table saw.
    • ___________ _________ __________
    • If you were working 3 inches from the point operation, the guard opening would be ____ inches maximum.
    • Belts and pulleys under ____ feet would need guarding.
  • Resources
    • Here is the OSHA eTool site.
    • has a video from Oregon OSHA on the topic.
    • Every state has free consultation available to small employers.
  • Further
    • This was prepared as a collaborative effort several friends as a preliminary aid for anyone covering basic machine guarding.
    • These are just some the issues. A comprehensive job hazard analysis should be conducted for any task where someone can get hurt.
    • This is not an official OSHA publication. Those will be on the website.
    • [email_address] is my email if you see any errors
    • 312-353-5977
    • I want to thank Ron Stephens, Sharon H. Merri M. Misette K, Jim W. and Aaron P. for all their assistance in answering questions and providing insight to the many hazards in this sector.