The Science:

 

Vibration refers to the “oscillatory motions of solid bodies and arises from mechanical sources with which humans have physical contact” (Groothoff, 2012, p. 1). Vibration consists of oscillatory movements of particles (molecules) around their equilibrium in a solid body, liquid or gas, in the area of infrasound (i.e. < 20 Hz), and partially also in the audible sound frequency range (up to 1500 Hz). Because in industrial situations vibration usually occurs in air – in the audible frequency range – it is normally also experience it as sound (Groothoff, 2012, p. 12).

 

Comcare (2015) describes two main types of vibration exposure: 

Whole body vibration: when vibration is transmitted through the whole body usually via a supporting surface, for example, a seat or floor in heavy vehicles or machinery; and

Hand-arm: when vibration is transferred through a vibrating tool, steering wheel or machinery controls

 

Occupational exposures to whole-body vibration mainly occur in transport but also in association with some industrial processes. Generally, exposures to hand-arm vibration are associated with “vibration of hand-held tools and workpieces” (Groothoff, 2012, p. 1).

Risk Potential:

 

Whole Body Vibration: 

 

The transmission of vibration to the body is dependent on body posture. The effects of vibration are complex. Exposure to Whole Body Vibration causes motions and forces within the human body that may:

• cause discomfort

• adversely affect performance

• cause health effect or aggravate pre-existing conditions

• present a health and safety risk.

 

The longer a worker is exposed to Whole Body Vibration, the greater the risk of health effects and musculoskeletal disorders. The most commonly reported disorder from exposure to Whole Body Vibration is low-back pain. Exposure to Whole Body Vibration may also cause or exacerbate other health or safety effects such as:

• cardiovascular, respiratory, endocrine and metabolic changes (for example - changes in blood pressure)

• digestive problems

• reproductive organ damage

• impairment of vision, balance or both

• Faults in the vestibular system of the ear

• Fatigue, general reduced efficiency

• interference with activities and discomfort that could lead to accidents.

 

These effects can also be impacted upon by factors including: the work environment, the dominant frequencies of the vibration exposure, and the ability to change postures during the exposure period (Groothoff, 2012, p. 3, Safe Work Australia, 2012).

 

The main sources of harmful WBV in vehicles and machines are:

• rough road and surface conditions and resistance forces, e.g. mobile plant with scraper blades

• vehicle activity

• engine vibration. (Safe Work Australia, 2012).

 

Hand Arm Vibration:

 

Exposure to HAV can result in disrupted circulation in the hand and forearm and/or damage to nerves and tendons, muscles, bones and joints of the hand and arm. It can cause a range of conditions collectively known as hand–arm vibration syndrome (HAVS) and specific disorders such as carpal tunnel syndrome, ‘tennis elbow’ and ‘vibration white finger’ (Safe Work Australia, 2012)

 

Approximately 24% of Australian workers were exposed to vibration in their workplace.

The industries where workers are reported to have the highest likelihood of exposure to vibration were:

• Agriculture, forestry and fishing,

• Transport and storage and

• Construction. 

The occupations in which workers are reported to have thehighest likelihood of  exposure to vibration include:

• Machinery operators and drivers,

• Technicians and trades workers, and

• Labourers (Groothoff, 2012, p. 4).