Portable Grinder Safety

1. Portable Grinder Safety

2. Background The portable grinder is used in the field or maintenance shop to grind excess metal from welds, remove rust, and for special finishing operations. Since this tool is hand operated, the quality of the work depends upon the ability and experience of the operator … as does safe job completion.

3. Background, continued Since the grinder is such a common tool (you will find one or more on almost every maintenance or construction job) the risks involved with them may tend to be taken for granted Perceived Risk Frequency Low Personal Awareness !!

4. What are the Common Hazards of Portable Grinder Use? • High speed flying particles … a grinding wheel’s speed can be greater than a mile a minute • from the grinding wheel itself • from the work piece being ground • Inhaling dust and fumes generated • Explosion or fire • if sparks ignite flammable or combustible materials nearby or below grinding operation • Electric shock from frayed or defective power cord • Noise • Musculoskeletal disorders (MSDs) from • repetitive use • awkward body positions

5. Common Injuries Due to Grinders/Grinding Activities • Cuts • Strains • Particles in the eye Grinders have contributed to fatalities !!! (flying particles cutting major artery for example)

6. Common Causes of Grinding Incidents • Using the wrong wheel • for the job or grinder • Improper mounting • of wheel or guard • Careless handling • Repetitive motion • Improper PPE use • Improper use of grinder

7. Critical Grinder Wheel Safety Issues Some Grinding wheels can be surprisingly delicate. They can be easily damaged if handled carelessly. • Store new wheels carefully in a dry area close to the grinding operation. • When you have to carry one, do it very carefully. • Take special care not to drop it or to bump it against anything. • Never use a wheel that has been dropped or received a heavy blow, even if there is no apparent damage. • Replace wheels that are badly worn or cracked.

8. Using the Right Wheel • Ensure the wheel is designed for the machine’s size and speed and the material of construction of the work piece • Grinding disks are made from varying types of abrasive materials. They are classified according to weight, size, arbor hole size (hole in the middle) and Rotations Per Minute (RPM) and material to be used on. This information can be found on the disk. • Grinding blades are to be used for GRINDING only, DO NOT use to cut material. Use only the grinding face, not the back side of disk. • Cutting blades are classified according to size, bearing arbor hole size and thickness. This information is also found on the blades. • Cutting blades are used for CUTTING only. DO NOT grind with them. Use only the edge.

9. Wheel Example Cutting Blade Max RPM Size of Disk Type of Material can be used on

10. Wheel Mounting Safety • Disconnect power source before adjusting, oiling or changing accessories • Use only parts supplied or approved by the grinder's manufacturer • nuts, flanges, guards, blotters, etc. • Ensure wheel maximum speed is higher than grinder maximum speed • the grinder motor should burn up rather than the wheel flying apart • Inspect wheel or attachment for cracks or flaws • Clean wheel and grinder • Perform a “ring test” on wheels prior to mounting (not applicable to all type wheels or other attachments and accessories) • Gently tap a dry clean wheel with a light nonmetallic tool—perhaps screwdriver handle for light wheels or wooden mallet for heavier ones • The tap should produce a clear metallic “ping.” If the sound is more like a dull thud, the wheel is probably cracked and shouldn’t be used. • Be sure the wheel fits freely on the spindle. • Check that the arbor hole is the proper size for the grinder to be used • The spindle nut must be tightened enough to hold the wheel in place, without distorting the flange • some manufactures require wrenches for tightening the wheel • Ensure guard is replaced in the appropriate position • After mounting wheel or brush and replacing the guard, stand to the side and allow a one minute run-up at no load to test integrity and balance of the wheel

11. Other Accessories or Attachments • Do not use unless: • The manufacturer recommends or approves its use on the product • The accessory limitations and specifications match those of the grinder • speed, size, mounting and guarding requirements, etc. • The use of the accessory does not require the removal of or defeating of any guards, barriers or other safety-related devices • unless they are replaced by other appropriate guards or protective devices. Follow manufacturer’s instructions for mounting approved accessories or attachments.

12. Grinders come equipped with a wheel guard that must remain in place at all times to protect the operator from flying sparks and material Never operate without its guard in the proper place Use a guard supplied or approved by the tool manufacturer Report any missing, broken, or disabled guards Guard Mounting Safety “Proper” placement of tool guard may vary. Handles can be moved on some angle grinders (to allow for right or left handed operation). Unlike in the photo above, the guard must be between the handle and the wheel.

13. Proper Handling of Grinders • Always use two hands when using a portable grinder • To maintain control • The high speeds of the wheel can cause the grinder to fly off the metal • To keep both hands away from the hazard of the high speed rotation • if a hand or finger hits the moving wheel surface, injuries will result • if grinding on small pieces, may need to secure the work in a vise … DO NOT HOLD IN YOUR HAND

14. Repetitive Motion Precautions • Use firm hand grip force for control but without excessive force • Avoid anything that inhibits blood circulation. • squatting for extended periods • improperly fitted gloves • other restrictions to comfortable body mechanics • Avoid continuous vibration exposure. • Keep wrists as straight as possible • Avoid repeated bending of wrists and hands. • After each period of extended operation, exercise to increase blood circulation • flex wrists • change body position • Minimize extent of reaching • to maintain better control of the tool and better body position • To prevent potential repetitive motion injuries consider the need to • reposition the work piece or your body • rotate job duties • change work pace

15. Proper Grinder PPE • Goggles AND a full face shield • to prevent chips or particles from getting into your eyes • particles WILL fly in any grinding operation • take appropriate precautions on removing goggles or safety glasses to ensure particles don’t fly into your eye even AFTER the grinding operation is done • Leather Gloves • to protect your hands from flying particles and sharp edges created during the grinding operation, as well as the edge of the wheel itself • Hearing protection • Proper attire • don’t wear anything loose that could get caught in the rotation • secure scarves, ties, loose hair, and dangling jewelry • if you’re wearing a long-sleeved shirt, button it at the wrist • Consider also the possible need for a dust mask • may be required for some grinding operation, depending upon the material of construction of the work piece being ground Be sure to maintain use of PPE for as long as hazard remains !!!

16. Proper Use of Grinders • Unless otherwise designed, grind on the face of the wheel. • serious injury or damage could occur if the side of the wheel is used • use disc wheels for side-grinding • light side-grinding is permissible on cup or saucer wheels

17. Critical Safe Behaviors for all Powered Tools • Know and Follow all Manufacturer’s Instructions • Use tool only for its intended purpose • Maintain tools in proper condition • sharp & clean, lubricated • all guards in place • ensure any repairs performed by qualified persons • Do not alter tools • to force pieces that don’t fit • or otherwise use the tool for an unintended purpose • Perform a prior to use inspection of the tool • Protect against electrical shock • use appropriate grounding • ground plug in place, GFCI as appropriate • inspect cords & connections • don’t abuse cords, keep away from heat, oil & sharp edges, inspect for frays, cuts, etc.

18. Critical Safe Behaviors for all Powered Tools, continued • Ensure all guards, grips, handles, etc. are in place • Prevent unintentional starting of the tool • 2 motion positive on/off switch required • don’t carry powered tools plugged in with finger on switch • Never carry a tool by the cord or hose. • Never yank the cord or the hose to disconnect cord • Avoid accidental starting. Do not hold a finger on the switch button while carrying a plugged-in tool. • All portable electric tools that are damaged shall be removed from use and tagged "Do Not Use.“ • Protect others in work area • don’t allow cords to become trip hazards • minimize number of employees in hazard zone • ensure all in hazardous areas are using appropriate PPE • consider work in adjacent or below areas

19. Additional Grinder Specific Critical Behaviors • Allow grinder to come to full speed before contacting work surface • Remove material or debris that might be ignited by sparks • Keep a properly charged fire extinguisher available • Do not grind non-ferrous materials. • Maintain steady pressure on the work piece • sudden “bumping”, pounding or impact could damage the wheel • Do not apply excessive pressure to the wheel or disc so that the motor slows noticeably of the work gets hot • could stress the wheel, overheat the work piece and reduce your control • Avoid letting the wheel rest on one spot for too long. • could cause the work to burn or the wheel to crack and explode. • Keep good footing and maintain good balance • Never attempt to grind in an awkward position. • A portable grinder can kick and glance off the work if not properly controlled • Allow grinder to come to complete stop before removing PPE or setting tool down

20. Summary • Don’t take grinder safety for granted • Understand and respect the hazards • Before using a grinder, learn how to eliminate, reduce and protect against letting those hazards result in injury • If observing others using a grinder, reinforce the appropriate behaviors and coach for improvement on those at risk • Remember the close proximity rule – If you have employees within 10 Ft of your grinding operation they must maintain the same level of (eye / face ) protection. Zero is our Goal! Everyday!