Risk Health and Safety Training



Vibration - NEBOSH Quick Revision SheetIntroductionHand Arm Vibration Syndrome (HAVS)Whole of Body Vibration Syndrome (WBVS)Caused by holding or working with tools that vibrate at a frequency of between 2 to 1500 Hertz (Hz)Most hazardous range is 5 to 20 HzSome examples of tools causing vibration include:ChainsawsAngle-grindersPneumatic drillsWoodworking machineryCompressor gunsConcrete vibro thickenersWBV is the vibrating or jolting of the whole body through the surface that is supporting the body, such as a machine seat or floor.WBV often occurs through from driving or operating some types of construction plant or vehicles, had the potential to cause back injury or make an existing condition more painful.Mobile machine operators and drivers (especially those who work off-road) are at increased risk from back pain.Most work WBV is unlikely on its own to cause back pain.Those most likely to experience high vibration exposure are regular operators and drivers of off-road machinery:Construction, mining and quarrying machines e.g. scrapers, bulldozers and building site dumpers;Tractors and other agricultural and forestry machines, particularly turning hay, primary cultivation and mowing.Risk of InjuryWhat the Employer Must DoThe risk of vibration-related injury (HAVS and WBVS) depends on:The amount of vibrationThe length of time the equipment was usedThe conditions of useThe posture of the operativeThe temperature at which the work is carried out.Assess vibration risks to health and safetyEliminate vibration risk at source, or reduce to the lowest level reasonably practicableProvide information and training for employees on vibration risks and control measuresIf any legislative limit value is exceeded stop work and identify the reasons.In the UK the Control of Vibration at Work Regulations 2005 EAV and ELV ValuesExposure Action Value (EAV)Exposure Limit Value (ELV)For HAVS:2.5 ms-2 average over an 8 hour dayFor WBVS: 0.5 ms-2 averaged over an 8 hour day.If this value is reached or exceeded the employer should try to reduce the exposure to the lowest level reasonably practicable.If the exposure cannot be reduce, then the exposed operatives are required to be enrolled in an annual health surveillance programmed to detect and possible symptoms early before it becomes a chronic health issue.For HAVS:5.0 ms-2 average over an 8 hour dayFor WBVS: 1.15 ms-2 averaged over an 8 hour day.If this value is reached or exceeded the employer immediately investigate to determine why the ELV was exceeded and put controls measures in place to prevent it from happening again.Symptoms of HAVSVibration White Finger (VWF)Symptoms of HAVS falls into three broad categories:VascularNeurological; andMusculoskeletalSymptoms include:Tingling in the fingers – indication of poor blood supply;Vibration White Finger (see opposite);Numbness;Reduced sense of touch and feeling;Physical pain;Weak grip;Painful wrist; and Cramping of the hand and fingers (carpel tunnel syndrome)Circulation of the blood disorder:Usually set off by the coldEarly indications - the fingertips rapidly becoming pale and loss of feelingAttacks can produce numbness and ‘pins and needles’White phase followed by intense red flush (sometimes preceded by bluish phase) signalling return of bloodThe above accompanied by uncomfortable throbbingControl Measures for HAVS and WBVSEmployee information, instruction and training (see opposite);Selection of equipment that has been designed to either eliminate or reduce exposure of vibration to operatives (well-designed cabs/seats & tool grips);Assessing the risks using the manufacturers / suppliers vibration figures and estimated exposure times (HAVS calculator on HSE website);Remoting the operative from the machine, such as putting a road breaker on the end of a mini-digger;Ensuring work equipment is maintained to keep it in good working order to prevent machine vibration increasing over time;Ensuring work bits are honed and kept sharp so that the tool does the job and not the operating applying their weight onto the tool and thus increasing vibration exposure.Reducing the time operatives are expose to the vibration and employing job rotation; andEnsuring operatives keep warm and dry, the blood supply is the body’s protection system and promoting good blood flow will reduce the likelihood of suffering vibration health issues.Employee TrainingCorrect selection of equipmentCorrect operation of equipment (important with some vibration reduced designs);posture of use, tense muscles will suffer more damage;How to recognise and report symptoms of HAVS / WBVS;How to minimise risk (exercising finger, breaks from exposure, not smoking etc).Health SurveillanceParts that contribute to Vibration (HAVS & WBVS)A risk exists with vibration even after all control measures have been implemented and therefore a programme of health surveillance is often required.Vibration health surveillance would be done as a part of an overall health surveillance programme for employees and would include:Grip test;Dexterity tests; andSense of touch and feeling tests.Worn bearings;Dirty fans (unbalancing);Misaligned shafts;Unbalanced rotating parts;Loose bolts;Damaged gear teeth;Blunt cutting tools and blades;Worn suspension components;Incorrect tyre pressures;Damaged seats; andDamaged tyres/tracks. ................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download