NOISE CONTROL FOR HIGHWAYS WORKERS – MEASURING AND REPORTING THE BENEFITS

By Dr David Greenberg, Eave Founder and CEO

In life and at work we use our eyes and ears to communicate and to stay safe. This is especially true for highway workers who are always operating with the risk posed by the unpredictability of civilian drivers. The standard approach to protecting our eyes when they are at risk at work is to wear see-through protective glasses. However, the modern approach to protecting our ears at work is to block them with pieces of plastic that we can’t hear-through – this is completely illogical. 

When working on the highways, operatives are often forced into choosing to protect their hearing or protect their lives, removing their hearing protection in order to maintain awareness of their environment. This is untenable because, not only do employers have a legal duty to protect the hearing of operatives (under the Control of Noise at Work Regulations 2005), noise exposure can be devastatingly harmful to both our hearing and overall health. It is the most common preventable cause of hearing loss deafness, which we now know is the number one preventable risk factor for dementia. £360 million was spent by insurance companies on occupational deafness claims in 2014 and it is still the most commonly reported occupational disease in the EU.

Despite advancements in our understanding of the life-long negative health consequences of noise exposure, there are cross-sector failings in our ability to manage noise at work effectively. A key reason for this is that measuring and reporting the benefit of noise control interventions has traditionally been the domain of experts in acoustics or simply deemed to be too difficult. My background as an NHS Audiologist left me appalled at the state of the UK’s hearing health and its impact on relationships and safety at work, suggesting that something more needed to be done to prevent noise exposure at source.

There is no single technique or solution that is appropriate for every noise control requirement on the highway, so a good understanding of operations and work processes is necessary in order to determine the most effective intervention.

The hierarchy of noise control

Occupational safety and health professionals should follow the hierarchy of noise control, a widely accepted model of hazard control promoted by the Health and Safety Executive, when deciding what risk management mechanisms they will use to tackle noise-related issues during highway works:

Elimination of the noise source is the most effective way to prevent risk to workers. Examples include avoiding the use of noisy processes or machinery, elimination of impacts between hard objects or surfaces, outsourcing the noisy work processes and moving the noisy operations away from other work activities.

Substitution by replacing noisy machinery or equipment with quieter alternatives, when elimination is not possible, is often the next-best alternative to protect workers from exposure to noise. Performing a task differently can also protect the workers from noise.

Engineering controls involve making changes to processes, machinery or equipment to reduce exposure to noise. Some engineering measures include separating noisy areas from other workspaces, avoiding metal-to-metal contact by using plastic bumpers, replacing loose parts, worn bearings and gears and undertaking regular maintenance of equipment.

Administrative controls can be applied to the way the work is organised to reduce either the number of workers who are exposed to noise or the length of time they are exposed to noise. Some administrative controls include identifying hearing protection zones and clearly sign-posting noisy areas, organising schedules so that noisy tasks are performed when as few people as possible are present, limiting the time workers must spend in noisy areas and providing sufficient information and training to workers for the proper use of equipment.

Hearing protection is then the final option in the hierarchy of noise controls and should be used as a last resort after all efforts to eliminate or reduce noise levels have been exhausted. While hearing protection is the least effective intervention in reducing the risk of noise exposure, it is the most critical because it is the last line of defence.

The most common reasons that hearing protection fails are cited as: the interference it causes to communication, to hearing speech and warning signals; its effect on job performance was; incorrect use with other safety equipment; deterioration of the protection; and discomfort when wearing.

Hearing protection must be capable of reducing the noise reaching the wearer’s cochlea to a sufficiently safe level. However, it is when workers are over-protected that communication becomes difficult and individuals can find themselves working in isolation. Active or level-dependant hearing protection is therefore required to ensure the right level of protection is provided at all times.

From this point, how do you measure if your interventions have been effective?

Measuring and reporting the benefits of your noise control

To report the effectiveness of your noise control initiatives, you should gather data to answer the questions:

• How has the control measure changed the level of noise present?

• How has the control measure affected hearing protection wear-rates?

• How has the control measure affected an individual’s noise exposure dose? (100% dose is equivalent to 85dBA for 8 hours)?

Historically it would be near impossible to answer these questions with any level of accuracy, which means that managing noise has typically been seen as too difficult to do well. Today however, there are digital technologies that can be used to quickly and simply provide accurate answers, enabling industry wide reduction in exposure to noise. Ear defenders within-built noise monitoring capabilities, such as the FocusLite from Eave, can measure each individual’s dose of noise, taking employers from guessing exposure levels to accurate knowledge of risks. 

Being able to pinpoint who is being exposed above a specific dose allows occupational health professionals to focus on those people most at risk, rather than a blanket approach of screening the entire workforce. Combining the personal noise exposure data with noise mapping software, such as Peak from Eave, which visualises and analyses the data based on geographical location, provides the fastest, most accurate and cost effective way to evaluate noise exposure levels. This process makes reporting the benefits of the noise controls you have put in place simple and accurate.

The key here is that accurate knowledge of noise exposure is vital in order to address it and data from the source is critical to measure and report the benefits. Once understood, the necessary controls can be implemented without difficulty and continually improved.

More articles can be found on the Safer Highways Blogs here.