HEALTH AND SAFETY Whole-body vibration: causes, …

1 22 NAPIT0870 444 1392 AND SAFETYDr Wilf Archerwith a guideto the injuriesand illnessesrelated to thiscomplaintIn a previous issue we looked at the vibration damagethat can be caused to hands and fingers from usingpowered-hand tools. The problem is that hand-armvibration damage is fairly well-known. It tends to getmedia attention and it is fairly easy to control becausethere is a direct link between the damage caused andthe source , what tends to be forgotten is that simplethings like operating a dumper truck, riding in a van ordriving a fork lift truck can cause fatigue, insomnia,headaches and shakiness with symptoms similar tothose that many people experience after a long car orboat daily exposure over a number of years, thesesame Whole-body vibrations can result in a number ofhealth disorders affecting your entire body includingpermanent harm to internal organs, muscles, jointsand bone know that vibrating hand tools interfere withblood circulation (vascular effects) and nerves signals(neurological effects)

2 , thereby causing a tinglingsensation, loss of feeling, numbness, and acharacteristic blanching or whitening of the affectedparts of the hand-arm system known as whitefinger .Identify and manageAnd when we start to show these signs then we canhave a fair idea where to look for the cause. Thesymptoms of Whole-body vibration are not so readilyrecognisable and are often mistaken for otherunrelated conditions and ailments. The healthoutcomes are non-specific and can be difficult andextremely expensive to identify, manage and factors should not detract from the fact thatemployees, and in particular professional drivers, cansuffer debilitating ill HEALTH effects from whole -bodyvibration onus is on the employer to know the vibrationexposure that their workforce is exposed too,including the magnitude of vibration , distribution ofthe motion within the body , and the frequency,direction and effectsWhile there is a shortage of conclusive evidence toprovide a definite close-effect relationship betweenwhole- body vibration and injury or HEALTH damage, wecan, from the limited scientific studies, subjectivedata, biodynamic models and our knowledge of thephysical properties of the human body , establishsome of the likely HEALTH effects.

3 Spinal column disease and complaintsareperhaps the most common diseases associatedwith the long-term exposure to whole -bodyvibration, where the back is especially sensitive tothe 4-12Hz vibration range digestive system diseasesare often observedin persons exposed to Whole-body vibration overa long period of time. This is associated with theresonance movement of the stomach atfrequencies between 4 and 5Hz and cardiovascular system effectsresultingfrom prolonged exposure to Whole-body vibrationat frequencies below 20Hz. These result inhyperventilation, increased heart rate, oxygenintake, pulmonary ventilation and respiratory rate. The vibrational energy waves, much the same asnoise, are transferred from the energy source ahand tool or vehicle into the body of the exposedoperator. This is then transmitted through the bodytissues, organs and skeletal systems of the individualbefore it is dampened and the human body can tolerate certainlevels of vibrational energy but when exposed over along period of time it begins to deteriorate and failcausing a disruption in the body s natural processesand systems.

4 The HEALTH effects experienced byemployees vary considerably and factors such assituation, age, lifestyle (smokers), posture, ergonomicdesign and resonance all have an influence on the illhealth effects of the vibration part of the human body has its own naturalfrequency of vibration . The extent to which the humanbody is affected depends on the vibration frequencyto which it is resonant response to the vibration will causesymptoms ranging from simple motion sickness tosevere discomfort, organ failure or back painThe most pronounced and common effect is lowerback pain. This can be linked to the vibration actingon the musculo-skeletal system of the body , causingthe degeneration of the small cartilage (intervertebral)discs, allowing tissues and nerves to be strained andpinched leading to various back and neck periods of sitting while the spinal column isWhole- body vibration : causes , effects and curesNAPIT0870 444 1392 23uses, effects and curesbeing aggravated by vibration exposure causes thenutrients needed for growth and repair to diffuseoutwards.

5 This causes irreparable damage at acellular level and wear and reduced healing of discsand vertebra within the spinal fatigue also occurs as the muscles try toreact to the vibrational energy to maintain balanceand protect and support the spinal column. But theseare often too slow as the muscular and nervoussystem cannot react fast enough to the shocks andloads being applied to the HEALTH effects that have been associatedwith Whole-body vibration and especially the drivingenvironment are haemorrhoids, high blood pressure,kidney disorders and even impotence and otheradverse reproductive effects in men and is a complex hazard that does not have onecontrol measure that will solve all , it is not always necessary to spend greatsums of money on evaluation of vibration exposures,when a good risk assessment exercise is carried outtaking into account factors such as exposure periods,worker complaints and symptoms, medical recordsand ergonomic principles and design at theworkplace or on the vehicle.

6 If a driver or worker has a genuine complaint aforklift driver with lower back pain then somethingshould be done to try and rectify money could be spent on control measuresand include possible solutions such as air-ride suspended seats, suspended cabs, maintainingvehicle suspension systems, and inflating tyres totheir proper pressure. Seats with arm rests, lumbar support, anadjustable seat back and an adjustable seat pan arealso useful for correcting driving surfaces to reducevibration at the it takes is a true holisticapproach using sound occupational HEALTH and levels running through a : The tolerance limitsof the body to vibrationin a lorry : How the bottomof the back is affectedby LumbarVertebraSpinal CordVertibral BodyNutritionDiffusionSpinal CanalEyeball,Intraocularstructures (20 90 Hz)Shouldergirdle (4 5 Hz)Lower arm (16 30 Hz)Spinalcolumn(axialmode) (10 12 Hz)Head (axial mode) (20 30 Hz)Chest wall (5 10 Hz)Arm (5 10 Hz)Hand (30 50 Hz)Abdominalmass (4 8 Hz)Legs (variablefrom ca.)

7 2 Hz withknees flexingto over 20 Hz withrigid posture)