According to information submitted to the Reporting of Injuries, Diseases and Dangerous Occurrences Regulations 2013 (RIDDOR), 91 cases of Hand-Arm Vibration Syndrome (HAVS) were recorded among UK rail professionals during 2018/19. As the most commonly reported occupational health condition within the industry for the last nine years, such statistics have highlighted the need for rail organisations to control employees’ level of exposure to handheld power tools when carrying out engineering/maintenance works.
In this blog, Mary Cameron, team leader within SOCOTEC’s Occupational Hygiene team, discusses the impact that HAV exposure has on employees within the rail sector and the actions that organisations can take to effectively reduce and eliminate exposure.
As an employer within the rail sector, what do I need to do with regards to Hand-Arm Vibration exposure?
Employers are required to protect their employees against health and safety risks that arise from exposure to vibration at work. Estimating this risk and preventing unacceptable exposure to Hand Arm Vibration (HAV) is crucial to avoiding adverse health effects. The Control of Vibration at Work (CVW) Regulations 2005 require employers to carry out a HAV risk assessment, provide information, instruction and training to employees on the risk and control measures being taken, as well as implement suitable health surveillance if exposure levels exceed the daily exposure action value (EAV) of 2.5 m/s2 A(8).
The paramount focus should always be to keep employees’ level of exposure to HAV ‘as low a level as is reasonably practicable’ (ALARP). Organisations must ensure that the risk of vibration exposure is either eliminated at source or, where this is not reasonably practicable, reduced to ALARP. If exposure is above the EAV, the risk assessment must be reviewed and actions taken accordingly to reduce exposure levels further.
How do employees who are regularly exposed to HAV spot signs and symptoms?
Key symptoms of HAVS include tingling, numbness, pain, weakness and blanching (white fingertips) when cold, which can become red and painful upon recovery. While these symptoms may come and go, continued exposure to vibration may cause symptoms to become prolonged or even permanent, causing sleep disturbance, pain, and distress. The point at which symptoms present themselves varies, with some occurring after only a few months of exposure and others over the course of several years. However, as the symptoms of HAVS tend to be progressive, employees with early stages of the condition may be able to recover if exposure is stopped early enough.
Which employees within my rail organisation are the most vulnerable?
It is difficult to say who is the most vulnerable when it comes to HAV exposure, as the onset and level of harm can vary greatly from person to person. As a general rule, those at greatest risk will experience the highest level of exposure (e.g magnitude and duration of the vibration), as well as those using high vibration equipment for extended periods of time, such as rock drills, chain saws, concrete breakers, strimmers, chipping hammers, needle guns and portable grinders.
I have undertaken a risk assessment which indicates that my employee’s daily exposure level is likely to exceed the EAV – what should I do?
As an employer, you must take actions to reduce vibration exposure where possible by implementing adequate control measures and applying health surveillance when action levels are reached. It is crucial to bear in mind that should daily exposure levels lie just below (but not exceed) the EAV, this does not necessarily mean that your employees are safe. The EAV represents a level of clear risk that requires action via effective management and control measures, and is never deemed as ‘safe’ by the Control of Vibration at Work Regulations. In fact, there is evidence to suggest that implementing a health surveillance programme at daily HAV exposure levels above 1.0 m/s2 A(8) would be more protective of health, as it is more likely that the early development stages of HAVS will be caught and corrective actions taken.
Do I need to have my equipment measured for vibration levels?
As per the Control of Vibration at Work Regulations, risk assessments are conducted by identifying an employee’s daily exposure to vibration, determining ‘trigger’ times and referring to information on the probable magnitude of vibration and, if necessary, measurements on the magnitude of vibration. However, it is not a legal requirement for on-tool measurements to be taken. The employer is merely required to source the general range of the tool’s expected vibration magnitude.
As equipment manufacturers are legally required under the Supply of Machinery (Safety) Regulations 2008 to provide information on the tool’s vibration emission levels, employers are able to access the vibration magnitude data.. This provides organisations with a ballpark figure to allow purchase of low vibration tools and provides the relevant information required to carry out a preliminary risk assessment. However, HSE guidance states that vibration test codes (which determine vibration emissions data) tend to underestimate the vibration of equipment used in the workplace. In most cases, it is therefore advised to multiply the manufacturer’s declared emissions value by 1.5 to 2 for electric and pneumatic tools.
Many occupational hygienists would agree that on-tool measurements are a more accurate reflection of determining process-specific HAV exposure levels (conditions created when using a specific tool to carry out a specific job on a specific material). This is in comparison to the manufacturer’s declared vibration emissions values, which are examined under laboratory conditions and tend to be representative of the average amount of vibration generated from the main applications of the tool.
Nevertheless, although on-tool measurements arguably provide more accurate readings of vibration exposure levels, the subsequent control measures applied would be the same if both these measurements and the manufacturer’s data were to produce the same general range of vibration magnitudes. As long as the employer has sourced the general range of the tool’s expected vibration magnitude during that process, both the manufacturer’s data and on-tool measurements can provide the information needed to sufficiently assess the level of risk and control measures required. In either case, the principle of ALARP remains of paramount importance.
How can I control my employees’ level of exposure to HAV?
Employers can prevent overexposure to HAV among their employees by applying a number of different control measures, including:
- Avoiding exposure altogether by applying alternative working methods that eliminate the need for vibratory equipment
- Implementing a ‘buy smooth’ policy to ensure that only equipment that offers the lowest vibration magnitude levels possible is purchased
- Limiting the duration and magnitude of vibration exposure as far as is reasonably practicable
- Placing equipment on an appropriate maintenance programme
- Providing rest facilities that allow workers a sufficient amount of time to rest and warm up between periods of HAV exposure
- Encouraging employees to massage and exercise their fingers during work breaks
- Training employees on the correct usage of equipment to raise awareness on how to minimise levels of exposure
- Providing clothing that protects the worker from cold and damp so as to encourage good blood circulation
- Encourage the worker to quit smoking as this reduces circulation of blood to the fingers.
How useful is continual monitoring when it comes to assessing HAV exposure?
There is no legal requirement to undertake on-tool measurements for HAV, let alone carry out continual exposure monitoring. While the Control of Vibration at Work Regulations require the employer to assess an employee’s daily exposure to vibration, this does not mean that assessment of exposure levels should be undertaken on a daily basis.
Continual monitoring is generally only required in a specific set of circumstances, such as when workers have restrictions placed on their level of vibration exposure following medical advice, or when emergency work involving vibration exposure is necessary. However, it is worth noting that continual monitoring cannot by itself demonstrate control of exposure levels, and may actually provide a log of instances whereby the EAV had already been exceeded. Instead, employers should focus on the implementation and management of control measures that eliminate and/or substitute HAV exposure levels.
How can SOCOTEC help?
SOCOTEC’s highly experienced Occupational Hygiene team is best placed to support and advise your rail organisation when it comes to HAV risk assessments, with technical experts on hand to measure and assess HAV levels using human-vibration meters and tri-axial accelerometers.
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