From guessing to knowing: Connecting the dots of noise exposure monitoring

The Control of Noise at Work Regulations 2005 mandate that employers provide a worker with hearing protection if their daily or weekly average exposure exceeds 85 decibels. However, unless we are able to gain a reliable picture of actual noise exposure levels and how these evolve over time, regulations alone may not be enough to safeguard the workforce’s hearing effectively. Traditionally, connecting the dots between ‘guessing’ and ‘knowing’ real exposure levels has not been an easy task. 

Take, for example, a typical industrial plant environment. Noise exposure levels may vary significantly throughout the day and from one location to another. 

Technology can certainly play a key role in helping plant and safety managers rise to the challenge, yet, until recently, it has had its limitations. 

A sound level meter may tell you that the sound pressure in one section of the factory is relatively low, but step a bit closer to a machine and the actual noise level you are exposed to could be significantly higher. More importantly, a worker’s real exposure to noise may be higher than that of a colleague working in the same location, and using the exact same personal protective equipment, simply because they are not wearing it correctly or consistently.

Noise dosimeters on the other hand can be worn by the worker and provide a more accurate picture of noise levels across different locations, enabling safety managers to calculate an average of the noise levels workers have been exposed to over time. However these devices don’t provide information on the PPE’s attenuation levels, which is key to knowing the actual noise exposure levels.

Traditionally, the most common way of identifying attenuation levels has been the single number rating (SNR) value. Yet, the SNR is population-based and provides a very rough estimate of the potential attenuation that can be achieved from PPE when used correctly. For example, there can be a significant difference in individual attenuation levels from the same type of earplugs depending on how well the individual has fitted them. 

Connected approach

A more connected approach to hearing conservation may offer a solution. By integrating smart, wearable sensors with cutting-edge software and cloud-based services, the latest technology enables both workers and safety managers to measure and monitor noise exposure in real-time. This data can be used to implement proactive safety measures before hearing damage occurs.  

For example, some of the latest technologies activate an automatic fit-test during start-up, which tells the worker when they have fitted their hearing protection correctly. They also monitor sound exposure continuously, alerting the user whenever the permissible sound exposure level has been reached. Users can also perform a quick audiometric test to monitor their hearing threshold – and how this evolves over time – and be alerted as soon as a negative trend is detected.  

By embedding sensors in PPE to capture data at the point where the individual enters the working environment, the latest connected technology also enables safety and plant managers to track and analyse noise exposure data over time. This allows them to determine exactly how long a worker can stay on task and still be safe or change working patterns accordingly if necessary.   

Armed with real-time data and intelligence, plant and safety managers can check whether workers are wearing the right type of protective equipment and have had the correct training.

Exposure to noise can have a negative impact on focus and stress levels, which can be detrimental to productivity. Knowing that they can count on safety intelligence, workers can focus on their tasks without worrying about being protected. 

Ultimately, campaigns like the HSE’s new Helping Great Britain Work Well strategy highlight the need to shift the focus for action towards tackling long-term ill-health, not only immediate and visible threats to safety.  With this in mind, it is vital to identify exposure levels before it’s too late. A connected safety approach can help determine what actions are required to drive further improvements in safety and, increasingly, health.