ERGONOMIC VIBRATION

1. ERGONOMIC VIBRATION

2. WHO’S AT RISK? • ANYONE WHO ABSORBS MACHINE VIBRATION THROUGH THEIR HANDS AND ARMS WHILE WORKING A FAST-MOVING HAND TOOL -- • OR THROUGH THE BUTTOCKS AND THE SOLES OF THE FEET WHILE RIDING IN OR STANDING NEAR VIBRATING, HEAVY MACHINERY-- • RUNS THE RISK.

3. WHAT IS VIBRATION? • VASOSPASTIC, NEUROMUSCULAR, ARTHRITIC DISORDERS OF THE HANDS AND UPPER LIMBS • COMPOSITE OF VIBRATION INDUCED SIGNS AND SYMPTOMS (e.g. NUMBNESS, TINGLING OF THE FINGERS, EPISODIC BLANCHING OF THE FINGERS, PAIN, REDUCED GRIP STRENGTH AND DEXTERITY • RAYNAUD’S SYNDROME, WHITE FINGER

4. SYMPTOMS OF VIBRATION SYNDROME? • DISCOMFORT FROM COLD • TINGLING, NUMBING • BLANCHING FINGERS • PAIN

5. HOW MANY EXPOSED? • APPROXIMATELY 1.2 MILLION EXPOSED • 50 -- 60 % OF WORKER POPULATION HAVE SYMPTOMS

6. TYPES? • WHOLE BODY VIBRATION • SEGMENTAL VIBRATION

7. DEFINITION? • A CYCLE OF SPECIFIC ACTIVITY BACK-FORTH, UP AND DOWN RESULTING FROM REVERSAL OF ENERGY • FREQUENCIES OF 100 HZ OR HIGHER ARE ABSORBED BY THE HANDS AND WRISTS • FREQUENCIES UNDER 100 HZ ARE ABSORBED BY THE UPPER LIMB JOINTS

8. RESPONSE DEPENDS ON: • FREQUENCY OF VIBRATION • AMPLITUDE OF VIBRATION • TIME HISTORY OF VIBRATION EXPOSURE • DIRECTION OF VIBRATION • POINT OF APPLICATION OF VIBRATION • HOW MUCH VIBRATION IS TRANSMITTED • AFFECT OF CLOTHING AND EQUIPMENT • BODY SIZE (HEIGHT AND WEIGHT) • BODY POSTURE/ BODY TENSION

9. MAGNITUDE IS INFLUENCED BY: • TYPE, WEIGHT, AND CONDITION OF TOOL • ACCELERATION AND FREQUENCY PRODUCED BY TOOL • TOOL TYPE, ENVIRONMENTAL, ANTI-VIBRATION MATERIAL • OPERATING SPEED, ERGONOMICS OF USE • GRIPPING FORCES • ORIENTATION AND POSTURE OF THE HANDS, ARMS, AND BODY DURING WORK • PARTS OF HANDS IN DIRECT CONTACT WITH THE VIBRATING SURFACE

10. TOOLS MOST COMMONLY ASSOCIATED: • POWERED HAMMERS • CHISELS, CHAIN SAWS • SANDERS, GRINDERS, RIVETERS • BREAKERS, DRILLS, COMPACTORS • SHARPENERS, SHAPERS

11. CONTROL STRATEGIES: • ENGINEERING AND WORK PRACTICES • ANTI-VIBRATION CLOTHING, EQUIPMENT, AND TRAINING • GOALS: • REDUCE THE INTENSITY • REDUCE THE EXPOSURE DURATION • IDENTIFY THE EARLY SIGNS AND SYMPTOMS

12. ENGINEERING CONTROLS: • REDUCTION AT SOURCE • REDUCTION OF TRANSMISSION • PROCESS MODIFICATION

13. REDUCTION AT SOURCE • REDUCE SPEED OF TOOL • REDUCE WEIGHT AND POWER NEEDED TO DRIVE THE TOOL • CHANGE TYPE OF TOOL • E.G. RECIPROCATING ENGINE TO ROTARY OR ELECTRIC MOTOR • TOOL MAINTENANCE • MOUNT EQUIPMENT ON SPRINGS OR COMPRESSION PADS • USE MATERIALS THAT GENERATE LESS VIBRATION

14. REDUCTION AT TRANSMISSION • PROVIDE CUSHION TO ACT AS A VIBRATION ISOLATER IN A SEATED TASK • PROVIDE ANTI-FATIGUE MATS FOR STANDING OPERATION • DESIGN TOOLS TO REDUCE VIBRATION TRANSMITTED TO THE HANDS, • COUNTERWEIGHT TOOLS TO MINIMIZE GRIPPING REQUIRED TO OPERATE THEM • DAMPENING MATERIALS AND GLOVES ARE USUALLY MORE EFFECTIVE FOR HIGHER FREQUENCIES.

15. PROCESS MODIFICATION • CHANGES IN ANY ASPECT OF PROCESS TO ELIMINATE NEED FOR VIBRATING TOOLS OR EQUIPMENT • USING MECHANICAL AIDS (CHUCKS, CLAMPS) TO HOLD MATERIAL • REDUCES TIME OR INTENSITY OF EXPOSURE • ROBOTICS • AUTOMATION • SUBSTITUTION OF MATERIALS • PLASTICS FOR HARD METAL

16. WORK MODIFICATION APPROACHES • LIMIT NUMBERS OF HOURS • REDUCE NUMBER OF DAYS PER WEEK • ROTATE BETWEEN VIBRATING AND NON-VIBRATING TOOL TASKS • SCHEDULE MAINTENANCE BREAKS

17. WORK PRACTICES • LENGTH OF WORK DAY • JOB ROTATION • SELECT LOW VIBRATION TOOLS • DESIGN WORK TASK AND WORKPLACE ERGONOMICALLY • REDUCE GRIP FORCE APPLIED • REDUCE FORCE APPLIED • RESTRICT USE OF PIECE WORK AND INCENTIVE PAY • ERGONOMIC WORK POSTURES

18. ADMINISTRATIVE CONTROLS • PPE • REDUCE TRANSMISSION OF VIBRATING ENERGY TO THE HAND • PROTECT AGAINST EXPOSURE TO COLD AND TRAUMA • TRAINING • SOURCE OF VIBRATION • ADVERSE HEALTH AND SAFETY EFFECTS • EARLY SIGNS AND SYMPTOMS • USE AND AVAILABILITY OF VIBRATION PROTECTIVE CLOTHING • ANTI-VIBRATION DEVICES • VALUE OF GOOD TOOL MAINTENANCE • WORK PRACTICE PROCEDURES