Objectives Course No 204 Machinery and Machine Guarding

Objectives Course No. 204 Machinery and Machine Guarding Standards Course • Identify basic machinery terms • Identify common machines found within a broad spectrum of industries • Identify hazards that occur in or on machinery • Select the appropriate OSHA STANDARD that applies to a hazard • Present options to achieve abatement Slide 1 (of 185)

Dangerous moving parts in these three basic areas need safeguarding: • The point of operation: that point where work is performed on the material, such as cutting, shaping, boring, or forming of stock. • Power transmission apparatus: all components of the mechanical system which transmit energy to the part of the machine performing the work. These components include flywheels, pulleys, belts, connecting rods, couplings, cams, spindles, chains, cranks, and gears. • Other moving parts: all parts of the machine which move while the machine is working. These can include reciprocating, rotating, and transverse moving parts, as well as feed mechanisms and auxiliary parts of the machine. Slide 2 (of 185)

Hazardous Rotating Motion Burr Rotating shaft Rotating pulley Rotating coupling Slide 3 (of 185)

Rotating (including in-running nip points) Slide 4 (of 185)

Hazardous Reciprocating Motion Slide 5 (of 185)

Hazardous Transverse Motion Slide 6 (of 185)

What must a safeguard do to protect workers against mechanical hazards? Slide 7 (of 185)

• Prevent contact: – The safeguard must prevent hands, arms, or any part of a worker's body or clothing from making contact with dangerous moving parts. A good safeguarding system eliminates the possibility of the operator or other workers placing parts of their bodies near hazardous moving parts. • Secure: – Workers should not be able to easily remove or tamper with the safeguard, because a safeguard that can easily be made ineffective is no safeguard at all. Guards and safety devices should be made of durable material that will withstand the conditions of normal use. They must be firmly secured to the machine. • Protect from falling objects: – The safeguard should ensure that no objects can fall into moving parts. A small tool which is dropped into a cycling machine could easily become a projectile that could strike and injure someone. Slide 8 (of 185)

• Create no new hazards: – A safeguard defeats its own purpose if it creates a hazard of its own such as a shear point, a jagged edge, or an unfinished surface which can cause a laceration. The edges of guards, for instance, should be rolled or bolted in such a way that they eliminate sharp edges. • Create no interference: – Any safeguard which impedes a worker from performing the job quickly and comfortably might soon be overridden or disregarded. Proper safeguarding can actually enhance efficiency since it can relieve the worker's apprehensions about injury. • Allow safe lubrication: – If possible, one should be able to lubricate the machine without removing the safeguards. Locating oil reservoirs outside the guard, with a line leading to the lubrication point, will reduce the need for the operator or maintenance worker to enter the hazardous area. Slide 9 (of 185)

Machine Safeguarding Classifications Slide 10 (of 185)

Machine Safeguarding Classifications • Guards • Fixed • Interlocked • Adjustable • Self-adjusting • Devices – Presence Sensing • Photoelectric (optical) • Radiofrequency (capacitance) • Electromechanical – Pullback – Restraint – Safety Controls • Safety trip control – Pressuresensitive body bar – Safety tripod – Safety tripwire cable • Two-hand control • Two-hand trip – Gates • Interlocked • Other Slide 11 (of 185)

Machine Safeguarding Classifications • Location/Distance • Miscellaneous Aids • Potential Feeding and – Awareness barriers Ejection Methods – Miscellaneous – Automatic feed protective shields – Semi-automatic – Hand-feeding tools feed and holding fixtures – Automatic ejection – Semi-automatic ejection – Robot Slide 12 (of 185)

Fixed Guards - Provides a Barrier Advantages – Can be constructed to suit many specific applications – In-plant construction is often possible – Can provide maximum protection – Usually requires minimum maintenance – Can be suitable to high production, repetitive operations Limitations – May interfere with visibility – Can be limited to specific operations – Machine adjustment and repair often require its removal, thereby necessitating other means of protection for maintenance personnel Slide 13 (of 185)

Fixed Point of Operation Guard Slide 14 (of 185)

Interlocked Safeguarding Action – Shuts off or disengages power and prevents starting of machine when guard is open; should require the machine to be stopped before the worker can reach into the danger area Advantages – Can provide maximum protection – Allows access to machine for removing jams without timeconsuming removal of fixed guards Limitations – Requires careful adjustment and maintenance – May be easy to disengage Slide 15 (of 185)

Adjustable Safeguarding Action – Provides a barrier which may be adjusted to facilitate a variety of production operations Advantages – Can be constructed to suit many specific applications – Can be adjusted to admit varying sizes of stock Limitations – Hand may enter danger area protection may not be complete at all times – May require frequent maintenance and/or adjustment – The guard may be made ineffective by the operator – May interfere with visibility Slide 16 (of 185)

Self-Adjusting Safeguarding Action – Provides a barrier which moves according to the size of the stock entering danger area Advantages – Off-the-shelf guards are often commercially available Limitations – Does not always provide maximum protection – May interfere with visibility – May require frequent maintenance and adjustment Slide 17 (of 185)

Safety Devices • Stop the machine if a hand or any part of the body is inadvertently placed in the danger area; • Restrain or withdraw the operator's hands from the danger area during operation; • Require the operator to use both hands on machine controls, thus keeping both hands and body out of danger; or • Provide a barrier which is synchronized with the operating cycle of the machine in order to prevent entry to the danger area during the hazardous part of the cycle. Slide 18 (of 185)

Photoelectric Safeguarding Action – Machine will not start cycling when the light field is interrupted – When the light field is broken by any part of the operator's body during the cycling process, immediate machine braking is activated Advantages – Can allow freer movement for operator; simplicity of use; no adjustments required Limitations – Does not protect against mechanical failure – May require frequent alignment and calibration – Excessive vibration may cause lamp filament damage and premature burnout – Limited to machines that can be stopped Slide 19 (of 185)

Pullbacks Safeguarding Action – As the machine begins to cycle, the operator's hands are pulled out of the danger area Advantages – Eliminates the need for auxiliary barriers or other interference at the danger area Limitations – Limits movement of operator – May obstruct work-space around operator – Adjustments must be made for specific operations and for each individual – Requires frequent inspections and regular maintenance – Requires close supervision of the operator's use of the equipment Slide 20 (of 185)

Restraint (holdback) Safeguarding Action – Prevents the operator from reaching into the danger area Advantages – Little risk of mechanical failure Limitations – Limits movements of operator – May obstruct work-space – Adjustments must be made for specific operations and each individual – Requires close supervision of the operator's use of the equipment Slide 21 (of 185)

Safety Trip Controls Safeguarding Action – Stops machine tripped Advantages – Simplicity of controls Limitations – Other guards are also required for operator protection--usually fixed barrier guards – Requires frequent maintenance – May not be adaptable to stock variation Slide 22 (of 185)

Safety Trip Controls (cont’d) • When pressed by hand, the safety tripod deactivates the machine. • Because it has to be actuated by the operator during an emergency situation, its proper position is also critical. Slide 23 (of 185)

Safety Tripwire Cables Are located around the perimeter of or near the danger area. The operator must be able to reach the cable with either hand to stop the machine. Calender equipped with this type of control. Slide 24 (of 185)

Two Hand Controls Safeguarding Action – Concurrent use of both hands is required, preventing the operator form entering the danger area Advantages – Operator’s hands are at a predetermined location – Operator’s hands are free to pick up a new part after first half of cycle is completed Limitations – Requires a partial cycle machine with a brake – Some two-hand controls can be rendered unsafe by holding with arm or blocking, thereby permitting one-hand operation Protects only the operator Slide 25 (of 185)

Not Two Hand Controls Slide 26 (of 185)

Two Hand Trip • • Requires concurrent application of both of the operator's control buttons to activate the machine cycle, after which the hands are free. Trips must be placed far enough from the point of operation to make it impossible for the operator to move his or her hands from the trip buttons or handles into the point of operation before the first half of the cycle is completed. Slide 27 (of 185)

Gate • Movable barrier which protects the operator at the point of operation before the machine cycle can be started. Slide 28 (of 185)

Robots Press Robot Stock Conveyor Fixed Barrier Slide 29 (of 185)

Miscellaneous Awareness Barrier Slide 30 (of 185)

Shields Slide 31 (of 185)

Part 1910 Subpart O - Machinery and Machine Guarding • 1910. 211 - Definitions. • 1910. 212 - General requirements for all machines. • 1910. 213 - Woodworking machinery requirements. • 1910. 214 - Cooperage machinery. (Reserved) • 1910. 215 - Abrasive wheel machinery. • 1910. 216 - Mills and calenders in the rubber and plastics industries. • 1910. 217 - Mechanical power presses. • 1910. 218 - Forging machines. • 1910. 219 - Mechanical power-transmission apparatus. Slide 32 (of 185)

Horizontal v. Vertical Section 1910. 212 is a general (or (horizontal) standard that applies to all machines not specifically mentioned elsewhere in other sections of Subpart O. Other sections are specific (vertical) standards that apply to particular types of machines; e. g. , Section 1910. 213 applies to woodworking machinery. Slide 33 (of 185)

Machine guarding. 1910. 212(a)(1) • 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. Slide 34 (of 185)

1910. 212(a)(2) • 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. Slide 35 (of 185)

1910. 212(a)(3)(ii) The point of operation of machines whose operation exposes an employee to injury, shall be guarded. Slide 36 (of 185)

1910. 212(a)(4)Revolving Drums, Barrels, and Containers • Must be guarded by an enclosure which is interlocked with the drive mechanism. Slide 37 (of 185)

1910. 212(a)(5) Fan Blades • When the periphery of the blades of a fan is less than 7 feet above the floor or working level, the blades must be guarded with a guard having openings no larger than ½ inch. Slide 38 (of 185)

1910. 212(a)(6)Anchoring Fixed Machinery – Machines designed for a fixed location must be securely anchored to prevent walking or moving. Slide 39 (of 185)

What machines are covered by 910. 212 ? Slide 40 (of 185)

Presenting 1910. 212 Slide 41 (of 185)

OSHA Standards: • 1910. 212(a)(1) Machine guarding • 1910. 212(a)(3)(ii) Point of operation Hazards: • Contact with pinch points • Struck by hot metals • Caught in two die halves Reference Standard: Guarding Method: • Barrier guard Gates Video Clip Not in Handout Slide 42 (of 185)

Unguarded Dough Mixer Slide 43 (of 185)

OSHA Standards: • 1910. 212(a)(1) Rotating Parts • 1910. 212(a)(3)(ii) Point of operation Hazards: • Contact with rotating parts Reference Standard: • ANSI/AHAM FM-1 (food mixers) Guarding Method: • Interlocks What happened? • Employee by-passed interlock Result - Death Ingredient Mixer Slide 44 (of 185)

Injection Molding Machine OSHA Standards: Reference Standard: • 1910. 212(a)(1) Rotating Parts • 1910. 212(a)(3)(ii) Point of operation • ANSIB 151. 1 Guarding Method: • Interlocked barrier gate Slide 45 (of 185)

Injection Molding Machine (Plastic Molding) 1 - Electrical Interlock 2 - Hydraulic Interlock Slide 46 (of 185)

175 Ton Injection Molding Machine Mechanical Blocking Mechanism Interlocked Safety Gate Die Halves Stationary Platen Slide 47 (of 185)

Injection Molding Machine 3 - Mechanical Blocking Mechanism Prevents the dies from closing Slide 48 (of 185)

OSHA Standards: • 1910. 212(a)(1) Machine guarding • 1910. 212(a)(3)(ii) Point of operation Hazards: • Contact with pinch points • Struck by hot metals • Caught in two die halves Reference Standard: • Society of Die Cast Engineers – Die Cast Machine Safety) Guarding Method: • Barrier guard Die Casting Machines Video Clip Slide 49 (of 185)

OSHA Standards: • 1910. 212(a)(1) Nipping points • 1910. 212(a)(3)(ii) Point of operation Hazard (s): • Stuck-by molten aluminum • Contact with moving machine parts Reference Standard: • Society of Die Cast Engineers – Die Cast Machine Safety Guarding Method: • Barrier Guard Die Casting Operation Die Spit Shield Slide 50 (of 185)

OSHA Standards: Tubing Bender • 1910. 212(a)(1) Pinch Point – Struck by • 1910. 212(a)(3)(ii) Point of operation Hazard (s): • Caught in the clamp die • Contact with moving machine parts Reference Standard: • ANSI B 11. 15 Pipe Tube and Shape Bending Guarding Method: • Barrier guard • Foot pedal operation • Presence sensing device Slide 51 (of 185)

Swing Arm in Motion Slide 52 (of 185)

Addison Tube Bender Safety Mat and Foot Pedal Control Slide 53 (of 185)

Mechanical Power Press Brake OSHA Standards: • 1910. 212(a)(3)(ii) Point of operation Hazards: • Caught in the point of operation Reference Standard: • ANSIB 11. 3 Power Press Brakes Guarding Method: • Presence Sensing Devices • Two hand controls • Automatic barrier gates • Restraint device Slide 54 (of 185)

Point of operation hazard – CPL 2 -1. 25 Guidelines for point of operation guarding for power press brakes 4 inches Slide 55 (of 185) 4“

Press Brake Foot Treadle Operated With a Restraint Device Slide 56 (of 185)

Photo electric sensing across face and barrier across the ends of the press brake Press brake Slide 57 (of 185)

The Back of The Press Brake Awareness Guard Slide 58 (of 185)

Horizontal Metal Cutting Band Saw OSHA Standards: • 1910. 212(a)(1) Machine Guarding Hazards: • Contact with the unused portion of the saw blade Reference Standard: • ANSIB 11. 10 Sawing Guarding Method: • Telescoping barrier guard Slide 59 (of 185)

Metal Cutting Radial Saw OSHA Standards: • 1910. 212(a)(3)(ii) Point of operation guarding Hazards: • Contact with the saw blade Reference Standard: • ANSIB 11. 10 Sawing Guarding Method: • Side barrier guard Slide 60 (of 185)

OSHA Standards: • 1910. 212(a)(1) Nipping point Hazards: • Contact with rotating parts Reference Standard: • ANSI B 20. 1 Conveyors Guarding Method: • Barrier guard • Isolation • Control relocation Meat auger Slide 61 (of 185)

Screw Conveyor Guard does not meet requirement of Table O-10 Slide 62 (of 185)

Forming Mill Table May use safety trip wire? ? ? OSHA Standards: • 1910. 212(a)(3)(ii) Point of operation guarding Hazards: • Contact between the forming rolls and the material Reference Standard: • ANSIB 11. 12 Roll forming and Roll Bending Guarding Method: • Barrier guard (interlocked) • Presence sensing device Slide 63 (of 185)

Forming Mill In-running Nip Point of Operation Slide 64 (of 185)

Forming Mill Shows the process of metal forming – Metal is being pulled through dies and formed as it progresses. Slide 65 (of 185)

Back of a Shear – Material Take-off Conveyor OSHA Standards: • 1910. 212(a)(1) Machine guarding Hazards: • Contact between the belt and the pulley nip (drum) Reference Standard: • ANSIB 20. 1 Conveyors Guarding Method: • Barrier guard • Isolation Slide 66 (of 185)

Conveyor Nip Point Slide 67 (of 185)

Scissor Lift Table OSHA Standards: • 1910. 212(a)(1) Machine guarding Hazards: • Contact between the scissors arms Reference Standard: • ? ? Guarding Method: • Telescoping barrier guard • Isolation Slide 68 (of 185)

Pyramid or Pinch Roll Forming OSHA Standards: • 1910. 212(a)(3)(ii) Point of operation guarding Hazards: • Contact in the point of operation Reference Standard: • ANSI B 11. 12 Roll forming and bending Guarding Method: • Isolation • Limited barrier guards Slide 69 (of 185)

Pyramid or Pinch Roll Forming Point of Operation Slide 70 (of 185)

Roll Former Isolation Guarding Slide 71 (of 185)

REEL Paper Mill Pope OSHA Standards: • 1910. 212(a)(3)(ii) Point of operation guarding Hazards: • Contact in the point of operation Reference Standard: • ANSI B 11. 12 Roll forming and bending Guarding Method: • Isolation • Limited barrier guards Slide 72 (of 185)

REEL – Threading the Machine Paper Mill Pope In Running Nip Point Slide 73 (of 185)

REEL – Threading the Machine Paper Mill Pope Slide 74 (of 185)

REEL Paper Mill Pope Slide 75 (of 185)

REEL Paper Mill Pope Slide 76 (of 185)

Primary Arm Guard Slide 77 (of 185)

Lathe OSHA Standards: • 1910. 212(a)(1) Rotating parts Hazards: • Contact with rotating parts Reference Standard: • ANSI B 11. 6 Lathes Guarding Method: • Barrier guard Slide 78 (of 185)

Lathe Slide 79 (of 185)

Lathe Chip Shield Slide 80 (of 185)

Tapper OSHA Standards: • • Reference Standard: 1910. 212(a)(1) Machine guarding 1910. 212(a)(3)(ii) Point of operation guarding Hazards: • • • ANSI B 11. 8 Tapper Guarding Method: • Barrier guards and/or isolation Contact with rotating parts, chips and coolant Contact in the point of operation Slide 81 (of 185)

Vertical Boring Mills OSHA Standards: • 1910. 212(a)(1) Machine guarding Hazards: • Contact with rotating parts Reference Standard: • ANSI B 11. 8 Milling, drilling and boring machines Guarding Method: • Barrier guards Slide 82 (of 185)

Vertical Boring Mills Slide 83 (of 185)

Vertical Boring Mill Chip, and Rotating Part Guard Slide 84 (of 185)

Horizontal Boring Mill Slide 85 (of 185)

Mechanical Shear Hold down OSHA Standards: • • 1910. 212(a)(1) Machine guarding 1910. 212(a)(3)(ii) Point of operation guarding Hazards: • • Reference Standard: • ANSI B 11. 4 Shears Guarding Method: • Barrier guard Contact with shear blade Contact with hold down Slide 86 (of 185)

Shear in Operation Helper is exposed Slide 87 (of 185)

Hydraulic Shear Modified Guard Blade Slide 88 (of 185)

OSHA Standards: • 1910. 212(a)(1) Machine guarding • 1910. 212(a)(3)(ii) Point of operation Hazards: • Contact with mold halves • Contact with shuttle Guarding Method: • Barrier guards • Presence devices Core Making Machines Video Clip Slide 89 (of 185)

OSHA Standards: • 1910. 212(a)(1) Machine guarding • 1910. 212(a)(3)(ii) Point of operation Hazards: • Contact with angle shear or notcher • Contact with the punch and die Guarding Method: • Barrier guards Iron Worker Slide 90 (of 185)

Woodworking Machinery Requirements 1910. 213 Slide 91 (of 185)

• 10. 213(a)(9) All belts, pulleys, gears, shafts, and moving parts must be guarded in accordance with the specific requirements of 1910. 219. Belts Slide 92 (of 185)

1910. 213(c) Rip Saws • Circular table saws must have a hood over the portion of the saw above the table, so mounted that the hood will automatically adjust itself to the thickness of and remain in contact with the material being cut. • Must have a spreader aligned with the blade, spaced no more than one-half inch behind the largest blade mounted in the saw. • If used for ripping must have nonkickback fingers or dogs. Slide 93 (of 185)

1910. 213(d) Hand fed Crosscut Saw Shall Meet Requirements of (c)(1) Slide 94 (of 185)

10. 213(g) Swing Cutoff Saws • Hood that will completely enclose the upper half of the saw, the arbor end, and the point of operation at all positions of the saw. • Constructed in such a manner and of such material that it will protect the operator from flying splinters and broken saw teeth. • Automatically cover the lower portion of the blade, so that when the saw is returned to the back of the table the hood will rise on top of the fence, and when the saw is moved forward the hood will drop on top of and remain in contact with the table or material being cut. Slide 95 (of 185)

Slide 96 (of 185)

Slide 97 (of 185)

1910. 213 (h) Radial Saws • Upper hood that completely enclose the upper portion of the blade down to a point that will include the end of the saw arbor. • Sides of the lower exposed portion of the blade guarded to the full diameter of the blade. • Radial saw used for ripping shall be provided with nonkickback fingers or dogs. • Adjustable stop to prevent the forward travel of the blade beyond the position necessary to complete the cut in repetitive operations. • Installation such that the front end of the unit will be slightly higher than the rear, so as to cause the cutting head to return gently to the starting position when released by the operator. Slide 98 (of 185)

Radial Arm Saws Slide 99 (of 185)

Slide 100 (of 185)

1910. 213 (i) Bandsaws and Band Resaws • • • All portions of the saw blade shall be enclosed or guarded, except for the working portion of the blade between the bottom of the guide rolls and the table. Wheels fully encased. Outside periphery of the enclosure shall be solid. Front and back enclosed by solid material or by wire mesh or perforated metal. Guard for the portion of the blade between the sliding guide and the upper-saw-wheel guard shall protect the saw blade at the front and outer side. Self-adjusting to raise and lower with the guide. Slide 101 (of 185)

Band Saw Slide 102 (of 185)

Band Saw Slide 103 (of 185)

Slide 104 (of 185)

10. 213(j)(3) Hand-Fed Jointer • • • Automatic guard which will cover all the section of the head on the working side of the fence or gage. Effectively keep the operator's hand from coming in contact with the revolving knives. Automatically adjust itself to cover the unused portion of the head and shall remain in contact with the material at all times. Slide 105 (of 185)

1910. 213(m)(1) Wood Shapers and Similar Equipment • Cutting heads of each wood shaper, hand-fed panel raiser, or other similar machine not automatically fed, shall be enclosed with a cage or adjustable guard so designed as to keep the operator's hands away from the cutting edge. Slide 106 (of 185)

10. 213(o)(2) Cutting Heads on Wood- Turning Lathes • Covered as completely as possible by hoods or shields. Slide 107 (of 185)

1910. 213(p)(1) Sanding Machines • • • Feed rolls of self-feed sanding machines must be protected with a semi cylindrical guard to prevent the hands of the operator from coming in contact with the inrunning rolls at any point. Guard must be constructed of heavy material, preferably metal, and firmly secured to the frame carrying the rolls so as to remain in adjustment for any thickness of stock. The bottom of the guard should come down to within three-eighths inch of a plane formed by the bottom or contact face of the feed roll where it touches the stock. Slide 108 (of 185)

Circular Sander Slide 109 (of 185)

Unguarded belt sander Slide 110 (of 185)

Slide 111 (of 185)

Saw Blade 1910. 213(s)(7)&(8) Slide 112 (of 185)

Table Saw Slide 113 (of 185)

Swing Cut off Saw Slide 114 (of 185)

Table Saw Slide 115 (of 185)

Table Saw Slide 116 (of 185)

Belt Sander Slide 117 (of 185)

Table Saw Slide 118 (of 185)

Table Saw Slide 119 (of 185)

Power Molding Machine Slide 120 (of 185)

Table Saw Slide 121 (of 185)

Table Saw Slide 122 (of 185)

Dado Blade on Radial Saw Slide 123 (of 185)

Power Fed Rip Saw Slide 124 (of 185)

Radial Arm Saw Slide 125 (of 185)

Radial Arm Saw Slide 126 (of 185)

1910. 215 Abrasive Wheel Machinery Slide 127 (of 185)

Slide 128 (of 185)

Slide 129 (of 185)

Slide 130 (of 185)

1910. 215(a)(2) Guard Design • The safety guard shall cover the spindle end, nut, and flange projections. Slide 131 (of 185)

Safety Guard Slide 132 (of 185)

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. Work rest 1/8” Slide 133 (of 185)

1910. 215(b)(9) Tongue Guard Exposure adjustment one-fourth inch Slide 134 (of 185)

1910. 215(d) Mounting - Wheel Speed • (1) Inspection. – The spindle speed of the machine shall be checked before mounting of the wheel to be certain that it does not exceed the maximum operating speed marked on the wheel Slide 135 (of 185)

1910. 215(d) Mounting - Ring Test • (1) Inspection – Wheels should be tapped gently with a light nonmetallic implement, such as the handle of a screwdriver for light wheels, or a wooden mallet for heavier wheels. If they sound cracked (dead), they shall not be used. This is known as the "Ring Test". “Ring test” Slide 136 (of 185)

FLOOR STAND GRINDERS ANSI B. 7. 1 -1988 E 4. 3. 2 • Self Closing Guard – Effective two years after approval of this revision for existing machines, all floor stand grinders for use with a 24” diameter wheels or larger where personnel are required to be in the plane of rotation of the wheel shall be equipped with guards which close automatically in case of wheel breakage. Other guard designs which provide equivalent protection to the personnel in the plane of rotation of the wheel may be used. Slide 137 (of 185)

Slide 138 (of 185)

Guard Down Slide 139 (of 185)

Slide 140 (of 185)

Surface grinder with top guard Slide 141 (of 185)

29 CFR 1910. 219 Mechanical Power-Transmission Apparatus Slide 142 (of 185)

1910. 219(a) General Requirements • (1) This section covers all types and shapes of power-transmission belts, except the following when operating at two hundred and fifty (250) feet per minute or less: – (i) Flat belts one (1) inch or less in width, – (ii) Flat belts two (2) inches or less in width which are free from metal lacings or fasteners, – (iii) Round belts one-half (1/2) inch or less in diameter; and – (iv) Single strand V-belts, the width of which is thirteen thirtyseconds (13/32) inch or less. Slide 143 (of 185)

1910. 219(a) General Requirements • (2) Vertical and inclined belts (paragraphs (e) (3) and (4) of this section) if not more than two and one-half (2 1/2) inches wide and running at a speed of less than one thousand (1, 000) feet per minute, and if free from metal lacings or fastenings may be guarded with a nip-point belt and pulley guard. Slide 144 (of 185)

Belt speed exceeds one thousand (1, 000) feet per minute Slide 145 (of 185)

1910. 219(b) Flywheels • (1) Flywheels located so that any part is seven (7) feet or less above floor or platform shall be guarded in accordance with the requirements of this subparagraph: (7) feet or less above floor or platform shall be guarded Slide 146 (of 185)

LETTER OF INTERPRETATION This is in further response to your letter dated April 5, 1983, concerning the guarding of flywheels on power presses. The Occupational Safety and Health Administration's General Industry Standards 29 CFR 1910. 219(b)(1) and (b)(1)(vi) require guarding of the press flywheel. Furthermore, the latter provision requires that flywheels above working areas be provided with guards of sufficient strength to contain the flywheel in the event of shaft or wheel mounting failure. Reference to ANSI 815. 1 -1972, the current version of the source standard, rapidly demonstrates that structural failures are possible. Appendix AB. 1 of ANSI 815. 1 indicates that failures of a fatigue nature can be anticipated, particularly for older machines that have been continually exposed to cyclic leads. Therefore, substantial guarding is necessary to provide safety. That company die setter's need to have easy access to the flywheel for die-setting for is completely valid and should be a major consideration of the guarding provided. In that regard, the guard configuration enclosed is recommended for consideration. Slide 147 (of 185)

1910. 219(c) Shafting Burr Rotating shaft Rotating pulley Rotating coupling Slide 148 (of 185)

1910. 219(c)(2) Guarding Horizontal Shafting • (i) All exposed parts of horizontal shafting seven (7) feet or less from floor or working platform, excepting runways used exclusively for oiling, or running adjustments, shall be protected by a stationary casing enclosing shafting completely or by a trough enclosing sides and top or sides and bottom of shafting as location requires. Shafting must be guarded Slide 149 (of 185)

1910. 219(c)(4) Projecting Shaft Ends • • (i) Projecting shaft ends shall present a smooth edge and end and shall not project more than one-half the diameter of the shaft unless guarded by nonrotating caps or safety sleeves. (ii) Unused keyways shall be filled up or covered. Shafting shall not extend more than 1/2 the diameter of the shaft unless guarded Slide 150 (of 185)

1910. 219(d) Pulley Guarding • (1) 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. Slide 151 (of 185)

Slide 152 (of 185)

1910. 219(f) Gears, Sprockets, and Chains Slide 153 (of 185)

1910. 219(f) Gears • (1) Gears shall be guarded in accordance with one of the following methods: – (i) By a complete enclosure; or – (ii) By a standard guard as described in paragraph (o) of this section, at least seven (7) feet high extending six (6) inches above the mesh point of the gears; or – (iii) By a band guard covering the face of gear and having flanges extended inward beyond the root of the teeth on the exposed side or sides. Where any portion of the train of gears guarded by a band guard is less than six (6) feet from the floor a disk guard or a complete enclosure to the height of six (6) feet shall be required. Slide 154 (of 185)

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. Slide 155 (of 185)

1910. 219 (i) Collars and Couplings • • (1) Collars. All revolving collars, including split collars, shall be cylindrical, and screws or bolts used in collars shall not project beyond the largest periphery of the collar. (2) Couplings Shaft couplings shall be so constructed as to present no hazard from bolts, nuts, setscrews, or revolving surfaces. Bolts, nuts, and setscrews will, however, be permitted where they are covered with safety sleeves or where they are used parallel with the shafting and are countersunk or else do not extend beyond the flange of the coupling. Slide 156 (of 185)

1910. 219(m) Standard Guards General Requirements • (1) Materials – (i) Standard conditions shall be guarded by the use of the following materials. Expanded metal, perforated or solid sheet metal, wire mesh on a frame of angle iron, or iron pipe securely fastened to floor or to frame of machine. – (ii) All metal should be free from burrs and sharp edges. Slide 157 (of 185)

1910. 219(o) Approved Materials • (1) Minimum requirements. – The materials and dimensions specified in this paragraph shall apply to all guards, except horizontal overhead belts, rope, cable, or chain guards more than seven (7) feet above floor, or platform. Slide 158 (of 185)

1910. 219(o)(2) Wood Guards • (i) Wood guards may be used in the woodworking and chemical industries, in industries where the presence of fumes or where manufacturing conditions would cause the rapid deterioration of metal guards; also in construction work and in locations outdoors where extreme cold or extreme heat make metal guards and railings undesirable. In all other industries, wood guards shall not be used. W oo dg ua rd Slide 159 (of 185)