29 CFR 1910 SUBPART O Machine Guarding

OSHAs Most Cited Serious Violations in General Industry : FY 2007

Montana Public Sector Citations: CY 2008

Subpart O Sections Definitions General requirements for all machines Woodworking machinery requirements Abrasive wheel machinery Mills and calenders - rubber & plastics industries Mechanical power presses Forging machines Mechanical power transmission apparatus

General Requirements for All Machines

General Requirements (a)(1) Provide one or more methods of machine guarding o Protect operator and other employees in machine area from hazards created by point of operation Ingoing nip points Rotating parts Flying chips Sparks Etc.

General Requirements: (a)(2) Guards must be o Affixed to the machine where possible o Secured elsewhere if attachment is not possible o May not present hazard in itself

Point of Operation Must Be Guarded (a)(3) Point of Operation o Operator inserts or manipulates stock Cutting, shaping, or forming o Material is positioned & work is performed Shearing, punching, forming, or assembling. o All other points which may offer a hazard to operator or others in area

Point of operation: work is actually performed upon the material being processed

General Requirements (a)(4) Revolving drums, barrels, and containers o Guard by enclosure interlocked with drive mechanism

INTERLOCKING GATES

General Requirements (a)(5) Guard fan blades o Periphery of blades is less than 7' above the floor or working level o Maximum guard openings - 1/2 inch YES NO

General Requirements (b) Machines designed for a fixed location o Securely anchor

Guarding Requirements: Short Definition If it moves and can be reached o Guard it!

Rotating Parts & Nip Points

Nip Points Montana Occupational Safety & Health Training Institute

Big, Nasty Pinch Point

Actions

Horizontal & Vertical Standards o A general, or horizontal, standard o Applies to all machines not specifically mentioned elsewhere in Subpart O Other sections are specific or vertical o Apply to particular types of machines e.g., Section applies to woodworking machinery

WOOD CUTTING BAND SAW FALLS UNDER METAL CUTTING BAND SAW FALLS UNDER

Wood Working Machines

Woodworking Machines: Free from sensible vibration when o The largest size tool is mounted o Machine is run idle at full speed Firmly secure equipment

Guard: (a)(9) Guard All belts, pulleys, gears, shafts, and moving parts according to

Machine Controls: (b)(1) Operator must be able to cut off the power from each machine without leaving position at the point of operation

Machine Controls: (b)(3) Prevent machines from automatically restarting upon restoration of power

Special Hand Tools Used for placing and removing material Permit easy handling of material without operator placing hand in danger zone Are not substitutes for other required guarding o Supplemental protection o Not limited to woodworking

Hand Feeding Tools

Foot Pedals: (b)(6) Treadle to be protected against unexpected or accidental tripping Feeder attachments to be covered or guarded o Feed rolls o Other moving parts Also found under Power Presses

Foot Pedals Must be protected to prevent unintended operation o From falling or moving objects o By accidental stepping onto the pedal o Prevent bypassing Attach non-slip pad firmly to the pedal

Machine Guarding - Saws

Band Saws & Band Resaws Blades o Enclose or guard all portions of the saw blade Except for the working portion of the blade between the bottom of the guide rolls and the table o Guard portion of blade between the sliding guide and the upper saw wheel guard Protect saw blade at front and outer side Self adjusting to raise and lower with the guide

Band Saws & Band Resaws Fully encase band saw wheels o Solid outside periphery o Front and back enclosed by Solid material or By wire mesh or perforated metal

Band Saw

Band Saw Guard

Lathes: (o) Lathes used for turning long pieces of wood stock held only between the two centers o Equip with long curved guards extending over the tops of the lathes To prevent the work pieces from being thrown out of the machines

Transparent Guard on Lathe

Lathe Guards

DRILL PRESS Drill Press Lathe

Drill Press

Multi Use Guards Adjustable Slide Shields

SANDING MACHINES: (p) Belt sanding machines o Provide with guards at each nip point where the sanding belt runs on to a pulley Guards to effectively prevent hands or fingers from coming in contact with nip points Unused run of sanding belt to be guarded against accidental contact

Sanding Machines

Belt Sander Belt Sander Upper Guard - Left Side Mount

Belt Sander Take out of Service!

Inspection & Maintenance of Woodworking Machinery: (s) Immediately remove from service o Dull, badly set, improperly filed, or improperly tensioned saws Maintain cleanliness around woodworking machinery Provide push sticks or other hand feeding tools

Abrasive Wheel Machinery

ABRASIVE WHEEL MACHINERY: (a)(2) General requirements Guards must cover o The spindle end o Nut o Flange projections

ABRASIVE WHEEL MACHINERY: Excluded machinery Natural sandstone wheels Metal, wooden, cloth, or paper discs o With a layer of abrasive on the surface

ABRASIVE WHEEL MACHINERY: Work Rests o Rigid construction o Maximum opening of 1/8 o No adjustment with wheel in motion Tongue Guards o Helps keep pieces inside should wheel shatter o May never exceed 1/4

Work Rest 1/8 in. Tongue Guard 1/4 in.

A Shield Does Not Replace the Guards

FLANGES All abrasive wheels must always mounted between flanges o Not be less than 1/3 diameter of the wheel. o Some specific exceptions requiring other %

WHEEL INSPECTIONS Closely inspect & sound all wheels o Conduct ring test Assure no damage Check spindle speed of the machine before mounting wheel o Never exceed maximum operating speed marked on the wheel

RING TEST Gently tap wheels with a light nonmetallic implement o The handle of a screwdriver for light wheels o A wooden mallet for heavier wheels Tap about 45 degrees each side of the vertical centerline, about 1 or 2 from edge Rotate wheel 45 degrees & repeat test

RING TEST A sound and undamaged wheel will give a clear metallic tone If cracked, there will be a dead sound and not a clear "ring." o Do Not Use

Mechanical Power Transmission Apparatus

MECHANICAL POWER TRANSMISSION APPARATUS: Belts Flywheels Nip-point belt & pulley guard Chains & Gears

POWER TRANSMISSION Prime movers o Steam, gas, oil, and air engines o Motors o Steam and hydraulic turbines o Other equipment used as a source of power

POWER TRANSMISSION Cover all types and shapes of power transmission belts o Some specific exceptions Guard any part 7 feet or less above floor or platform o Or more

ENCLOSURE GUARDS Bevel Gear Guards

SHEAVE GUARDS

BELT & PULLEY ENCLOSURE GUARDS

FLYWHEEL GUARDING: (b) Enclosure of sheet, perforated, or expanded metal, or woven wire Guard rails placed not less than 15 nor more than 20 from rim o If flywheel extends into pit or is within 12 of floor, need a standard toeboard

Flywheel Guards

FLYWHEEL GUARDS

Guarding Shafts: (c) Protect all exposed parts of horizontal shafting seven (7) feet or less from floor or working platform

Rotating Shafts Rotating pulley Rotating coupling Burr Rotating shaft

ENCLOSURE GUARDS FOR ROTATING MOTION

Projecting Shaft Ends: (c)(4) Smooth edge and end May not project more than ½ diameter of shaft, or Guard by non-rotating caps or safety sleeves Fill or cover unused keyways

PULLEY Guarding: (d) Guard any parts 7 or less from floor or working platform Broken pulleys may not be used o Pulleys with cracks o Pieces broken out of rims

Lack of Pulley Guarding

PULLEY GUARDS

OVERHEAD PULEYS & BELTS Overhead Horizontal Overhead Traverse

GEARS: (f) Gears o Completely enclose o Use standard guard at least 7 high extending 6 above mesh point of gears

SPROCKETS & CHAINS: (f)(3) All sprocket wheels and chains must be fully enclosed o Unless more than 7 above floor May still be inadequate If drive extends over other machine or working areas o Provide protection against falling

KEYS, SETSCREWS, AND OTHER PROJECTIONS: (h) All projecting keys, set screws, and other projections in revolving parts must be o Removed o Made flush or o Guarded by metal cover

Wood Guards: (o)(2) Wood guards only allowed in o Woodworking and chemical industries o Industries where presence of fumes or manufacturing conditions would cause rapid deterioration of metal guards o Construction work and in locations outdoors where extreme cold or extreme heat make metal guards and railings undesirable

Guard Types & Requirements

Presses Press Brake Machine Guards