Presentation on theme: "1 Subpart O - Machine Guarding OTI 501 Paul Schlumper."— Presentation transcript:
1 Subpart O - Machine Guarding OTI 501 Paul Schlumper
2 We Will Cover: Machine Guarding Principles Subpart O - Highlights Mock Plant Walk-Through
3 Why are machines not guarded? No one would stick their arm, hand, finger, head, etc. in there. No one is supposed to be back there, in there, around it while it is running. The machine came that way; it never had a guard. Ive been doing it this way for twenty years without any problems.
4 Why are machines not guarded? (cont.) The guard is in the way The OSHA inspector didnt say anything about it. Well put it back on if OSHA comes.
5 Emphasis on Amputations : Where does it apply? General industry employers whose workplaces include: shears saws slicers slitters power presses (the 4s and a P)
6 Requirements for Safeguards Prevent contact - prevent workers body or clothing from contacting hazardous moving parts Secure - firmly secured to machine and not easily removed Protect from falling objects - ensure that no objects can fall into moving parts Create no new hazards - must not have shear points, jagged edges or unfinished surfaces Create no interference - must not prevent worker from performing the job quickly and comfortably Allow safe lubrication - if possible, be able to lubricate the machine without removing the safeguards
7 Where machine hazards occur: Point of operation Mechanical power transmission Other moving parts
8 Machine Hazards
9 Machine Guarding
10 In-Running Nip Points Belt and pulley Chain and sprocket Rack and pinion Rotating cylinders
11 Methods of machine safeguarding Physical guards Devices Location/Distance
16 Fixed Guard Provides a barrier - a permanent part of the machine, preferable to all other types of guards.
17 Interlocked Guard When this type of guard is opened or removed, the tripping mechanism and/or power automatically shuts off or disengages, and the machine cannot cycle or be started until the guard is back in place. Interlocked guard on revolving drum
18 Adjustable Guard Provides a barrier which may be adjusted to facilitate a variety of production operations. Bandsaw blade adjustable guard
19 Self-Adjusting Guard Provides a barrier which moves according to the size of the stock entering the danger area. Circular table saw self-adjusting guard
23 Pullback Device Utilizes a series of cables attached to the operators hands, wrists, and/or arms Primarily used on machines with stroking action Allows access to the point of operation when the slide/ram is up Withdraws hands when the slide/ram begins to descend
24 Pullback Device (contd) Hands in die, feeding Point of operation exposed Pullback device attached and properly adjusted Die closed Hands withdrawn from point of operation by pullback device
25 Restraint Device Uses cables or straps attached to the operators hands and a fixed point Must be adjusted to let the operators hands travel within a predetermined safe area Hand-feeding tools are often necessary if the operation involves placing material into the danger area
26 Safety Tripwire Cables Device located around the perimeter of or near the danger area Operator must be able to reach the cable to stop the machine
27 Two-Hand Control. Requires constant, concurrent pressure to activate the machine The operators hands are required to be at a safe location (on control buttons) and at a safe distance from the danger area while the machine completes its closing cycle
28 Gate Movable barrier device which protects the operator at the point of operation before the machine cycle can be started If the gate does not fully close, machine will not function Gate OpenGate Closed
29 Safeguarding by Location/Distance Locate the machine or its dangerous moving parts so that they are not accessible or do not present a hazard to a worker during normal operation Maintain a safe distance from the danger area
30 Automatic Feed (shown on power press) Transparent Enclosure Guard Stock Feed Roll Danger Area Completed Work
31 Robots Machines that load and unload stock, assemble parts, transfer objects, or perform other tasks Best used in high- production processes requiring repeated routines where they prevent other hazards to employees
32 Protective Shields These do not give complete protection from machine hazards, but do provide some protection from flying particles, splashing cutting oils, or coolants.
33 Holding Tools Used to place and remove stock in the danger area Not to be used instead of other machine safeguards, but as a supplement
35 Subpart O - Machinery and Machine Guarding Definitions General requirements Woodworking machinery Abrasive wheel machinery Mills and calendars Mechanical power presses Forging machines Mechanical power transmission
General Requirements for all Machines
(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 the point of operation, in- going nip points, rotating parts, flying chips and sparks.
(a)(3)(ii) The point of operation of machines whose operation exposes an employee to injury, shall be guarded
(a)(5) When the periphery of the blades of a fan is less than seven (7) feet above the floor or working level, the blades shall be guarded. The guard shall have openings no larger than 1/2 inch.
(b) Machines designed for a fixed location shall be securely anchored to prevent walking or moving.
Woodworking Machinery Requirements
(a)(9) All belts, pulleys, gears, shafts, and moving parts shall be guarded in accordance with the specific requirements of
(b)(1) A mechanical or electrical power control shall be provided on each machine to make it possible for the operator to cut off the power from each machine without leaving his position at the point of operation.
(b)(3) On applications where injury to the operator might result if motors were to restart after power failures, provision shall be made to prevent machines from automatically restarting upon restoration of power.
45 Table Saws
(c)(1) Each circular hand-fed ripsaw shall be guarded by a hood which shall completely enclose that portion of the saw above the table and that portion of the saw above the material being cut. The hood and mounting shall be arranged so that the hood will automatically adjust itself to the thickness of and remain in contact with the material being cut without considerable resistance.
(c)(2) Each hand-fed circular ripsaw shall be furnished with a spreader to prevent material from squeezing the saw or being thrown back on the operator.
(c)(3) Each hand-fed circular ripsaw shall be provided with non-kickback fingers or dogs so located as to oppose the thrust or tendency of the saw to pick up the material or throw it back toward the operator.
(d)(1) Each circular crosscut table saw shall be guarded by a hood which shall meet all the requirements of (c)(1) for hoods for circular resaws.
50 Radial Arm Saws
(i)(1) All portions of the saw blade (bandsaws) shall be enclosed or guarded, except for the working portion of the blade between the bottom of the guide rolls and the table.
(r)(4) The mention of specific machines in paragraphs (a) thru (q) and this paragraph (r) of this section, inclusive, is not intended to exclude other woodworking machines from the requirements that suitable guards and exhaust hoods be provided to reduce to a minimum the hazard due to the point of operation of such machines.
(s)(7) All cracked saws shall be removed from service.
(a)(4) Work rests shall be 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.
(b)(9) 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.
(d)(1) Immediately before mounting, all wheels shall be closely inspected and sounded by the user (ring test) to make sure they have not been damaged.
58 Abrasive Wheel Machinery The distance between the wheel periphery and the adjustable tongue must never exceed 1/4-inch.
Mechanical Power Presses
(a)(5) Press brakes, hydraulic and pneumatic power presses, bulldozers, hot bending and hot metal presses, forging presses and hammers, riveting machines and similar types of fastener applicators are excluded from the requirements of this section.
(b)(4) The pedal mechanism shall be protected to prevent unintended operation. A pad with a nonslip contact area shall be firmly attached to the pedal.
(b)(6) A two-hand trip shall have the individual operators hand controls protected against unintended operation and be arranged to require use of both hands. Two-hand trip systems on full revolution clutch machines shall incorporate an antirepeat feature. If two hand trip systems are used on multiple operator systems, each operator shall have a separate set of controls.
(b)(7) Two-hand controls must incorporate an anti repeat feature, require use of both hands, be protected against unintended operation, have one set of controls for each operator. If foot control is provided, the selection between hand and foot control must be supervised by the employer.
(c)(1) It shall be the responsibility of the employer to provide and insure the use of point of operation guards or properly applied and adjusted point of operation devices on every operation performed on a mechanical power press. See Table O- 10.
(e)(1) It shall be the responsibility of the employer to establish and follow a program of periodic and regular inspections of power presses.
(e)(3) It shall be the responsibility of the employer to insure the original and continuing competence of personnel caring for, inspecting, and maintaining power presses.
Mechanical Power-Transmission Apparatus
(b)(1) Flywheels located so that any part is 7 feet or less above the floor or platform shall be guarded. Wherever flywheels are above working areas, guards shall be installed having sufficient strength to hold the weight of the flywheel in the event of a shaft or wheel mounting failure.
(c) Horizontal, vertical, and inclined shafting must be enclosed. Projecting shaft ends shall present a smooth edge and end and shall not project more than 1/2 the diameter of the shaft unless guarded by non rotating cap or safety sleeves.
(d) Pulleys 7ft. or less above the floor or platform must be guarded. Pulleys with cracks or pieces broken out of rims shall not be used.
71 Portable Power Tools - General Safety Precautions (a) Employers responsibility Safe condition of tools Including personal tools (b) Compressed air not used for cleaning except where reduced to less than 30 p.s.i. and only when effective chip guarding and PPE.
72 Power Tools Classification by power source Electric Pneumatic Liquid Fuel Hydraulic Powder Actuated
73 Power Tools (cont.) (a)(1) – Portable Circular Saws Upper blade guard Lower blade guard Automatically returns to starting position
74 Power Tools (cont.) (a)(2) Constant Pressure Switch Saws and Chainsaws Lock-on control (single motion turnoff)
75 Pneumatic Power Tools and Hose (b) Tool Retainer – A tool retainer must be installed on each piece of equipment where ejection could result Airhose – Hose and hose connections must be designed for the pressure and service to which they are subjected
76 Explosive Actuated Fastening Tools (d) Must meet requirements in ANSI A Operators and assistants must wear eye protection Head and face protection dependent on working conditions
77 Explosive Actuated Tools (Cont.) Muzzle must have protective shield or guard at least 3 ½ inches in diameter. Firing must be dependent on at least 2 separate and distinct operations. Firing mechanism must prevent tool from firing during loading, while preparing, if dropped.
78 Explosive Actuated Tools (Cont.) Tools must not be loaded until just before intended firing. Do not point at anyone! Fasteners not driven into hard/brittle or easily penetrable material Tools not used in hazardous atmosphere
79 Lawnmowers 243(e) Meet the requirements of ANSI B71.1-X1968