Introduction to Physical Hazards
The individual hazard groups classified as physical agents are often subject to a variety of separate and specific regulations designed to manage the differing dangers posed to worker health.
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Noise
Personal exposure to high levels of noise at work either on a regular basis, or through very high levels of instantaneous impactive or explosive noise can cause ‘Noise induced Hearing Loss’ (NIHL) as well as tinnitus and other hearing disabilities such as threshold shift. Hearing loss and tinnitus are permanent and irreparable conditions with a significant impact on day-to-day lives.
An important consideration for preventing noise in the workplace is that it can contribute to safety risks, where communications are interfered with, or where workers are unable to hear warning sounds. Such conditions can easily occur in noisy workplaces, especially where workers need to use hearing protection and where individual workers suffer from some existing hearing loss.
Where possible, the presence of noise should be eliminated at the source or reduced to levels, so risks are minimal. Daily exposure, peak noise action levels and limit values should be adhered to ensure actions are taken at appropriate noise levels to protect of workers. This can include implementation of noise mitigation control measures, maintenance of control equipment, information and training of workers, and health surveillance.
Personal hearing protection can also be used in instances when other controls cannot adequately reduce exposures. Hearing protection must be selected to reduce noise exposures as far as possible without isolating the worker, which may compromise safety.
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Hand Arm Vibration
Workers are exposed to hand-arm vibration when using vibrating hand-held power or air tools, hand-guided or by holding materials being worked by hand-fed machines.
Exposure to hand-arm vibration for long periods on a regular basis can lead to the development of Hand Arm Vibration Syndrome (HAVS). This is a collective term for vascular, neurosensory, and musculoskeletal disorders within the hand and arm.
HAVS is a preventable occupational hygiene disease, however with prolonged exposure the symptoms can become permanent and largely irreversible with a significant impact on daily lives. Sufferers may have whitening (blanching) of one or more fingers and find it difficult to properly feel and manipulate items due to fingers tingling or a loss of sensation in the fingers and decreasing grip strength. All of which can result in simple everyday tasks such as reading a newspaper, cutting up food and even dressing becomes difficult.
Affected individuals may also suffer from Carpel Tunnel Syndrome, which leads to tingling, numbness, pain, and weakness in the hand. This which can interfere with work and everyday tasks and might affect the ability to do work safely.
The Vibration Regulations require employers to:
- to risk assess vibrations
- make sure that risks are controlled
- provide information and training on the risk
- provide information and training on actions being taken to control the risk
- provide suitable health surveillance.
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Whole Body Vibration
Exposure to whole-body vibration such as shaking or jolting movements when sitting or standing on vehicles or machinery.
Usually, hazardous exposures are associated with off-road vehicles in industries such as agriculture, forestry, mining, quarrying etc. Vehicles such as fork-lift trucks, cranes and even road-vehicles such as lorries and coaches also have the capability of producing high levels of whole-body vibration.
In conjunction with poor postures, poor designs of vehicle controls, incorrect ergonomics, manual handling and extended sitting times such exposures can lead to lower-back pain and injury, upper back and other musculoskeletal problems.
The Vibration Regulations require employers to:
- to risk assess vibrations
- make sure that risks are controlled
- provide information and training on the risk
- provide information and training on actions being taken to control the risk
- provide suitable health surveillance.
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Electromagnetic fields
Electromagnetic fields (EMFs) arise whenever electrical energy is used. Some EMF sources will produce field strengths that can be considered harmless. However, hazardous EMFs can arise from work processes such as welding, radiofrequency heating and drying, high-field magnetic resonance imaging scanners and high voltage power lines plus electrical power distribution.
Exposure to high levels of EMFs can give rise to a variety of health effects that depend on the frequency of the electromagnetic radiation. At low frequencies, the central nervous system can be affected, active or passive implanted or body worn medical device may be interfered with. Whilst at high frequencies, heating effects can occur.
Specific guidance on the Electromagnetic Fields at Work Regulations (2016) has been put in place by the Health and Safety Executive. This advises on:
- identifying sources
- assessing the exposure of employees
- deciding how, if anything, to your workers from the risk
- assessing and controlling any risks.
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Artificial Optical Radiation
Artificial optical radiation (AOR) includes light emitted from all artificial sources i.e., light in all its forms such as ultraviolet, infrared and laser beams, but excluding sunlight. It is likely that workers will be exposed to some form of artificial light at work, whether from general lighting, equipment or from a work process.
Dependant on the form of the AOR, the effects of exposure can be both acute and chronic, affecting mainly the skin and eyes.
Where the skin is affected, those exposed may suffer short-term effects of reddening (erythema), blistering and burns. Long-term exposures may cause skin ageing (elastosis) and skin cancer.
For the eyes, damage may include inflammation of the cornea (photokeratitis), inflammation of the conjunctiva that lines the eyelids and eye socket (photo conjunctivitis), retinal damage, corneal burns, retinal burns, and cataracts.
Specific guidance on the Artificial Optical Radiation at Work Regulations (2010) has been put in place by the Health and Safety Executive. This advises that workers in Great Britain are generally well protected from AOR and most businesses with hazardous sources know how to manage the risks effectively. Further work is only expected to be undertaken by businesses that use hazardous sources of AOR and where the risks have not been reduced to as low as is reasonably practicable.
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Thermal Stress
Heat stress occurs when the body’s means of controlling its internal temperature starts to fail. Air temperature, work rate, humidity and work clothing are all factors which can cause heat stress.
People working in uncomfortably hot and cold environments are more likely to behave unsafely because their ability to make decisions and/or perform manual tasks deteriorates.
Heat stress can affect individuals in different ways and some people are more susceptible to it than others. Typical symptoms include:
- Inability to concentrate
- muscle cramps
- heat rash
- severe thirst
- fainting
- heat exhaustion - fatigue, giddiness, nausea, headache, moist skin
- heat stroke - hot dry skin, confusion, convulsions, and eventual loss of consciousness. This is the most severe disorder and can result in death if not detected at an early stage.
Thermal stress risk assessments often should consider:
- Work rate
- Worker climate
- Worker clothing and additional PPE
- Worker age, build and medical history.