When we speak about noise or hearing conservation at the work place, as health and safety practitioners, our mindset nearly always takes us to what we have learnt about controlling high levels of noise. We start going back to our tried and tested ways of measuring levels of sounds that are above the 85 Decibel level (The Magic Number!). We start looking at ways to minimize the high level of noise, reduce the amount of hours the workers spend in the noisy areas, choosing the suitable PPE that needs to used and considering Noise Reduction Ratings (NRR).
From a health point of view, we look for signs of Noise Induced Hearing Loss (NIHL) through periodical audiometric testing. Organizations start this when employees join the company for the first time and then have follow up tests after so many years as part of their medicals or as part of their final leaving process. Hearing conservation training is common place for many of the industries where operations may present considerable noise Hazards, as part of these training sessions, employees learn about the concepts of attenuation, hearing protection, double hearing protection and the importance of controlling noises above….you guessed it….85 Decibels (The magic number again!)
While all of the above is good, proven, and has eliminated and minimized many noise concerns throughout the years, our current methods unfortunately do not address what I would like to call the “twilight zone” of hearing conservation! I am talking about the noise levels between 35 to 85 decibels. These levels often get ignored at the workplace as it is below the threshold levels where employees are required to take action.
As I went through my various occupational health studies and took on assignments to manage noise at my various workplaces, the safety standards nearly always referred to controlling risk at high sound frequencies and rarely touched upon the chronic long term effects caused by noise at low or medium levels. This is where the health part comes into play, and having a Zero Harm work mentality will require teams to look at the long term adverse effects impacting general employee wellness. Effects which may not always be within the critical ranges of workplace noise levels.
Knowing such implication would require practitioners to look beyond the immediate risk and examining the health aspects in more detail. The World Health Organization (WHO) for example, provide a much more in depth analysis of the impacts of noise within those ranges. They also provide some interesting statistics to the extent of the issue with an estimated 30 billion pounds being the annual cost to Europe as a result of excessive noise, much of it of course, down to lost working days, health care costs and reduced productivity.
Noise between the 35 to 85 dB range can trigger the body’s stress response. As a result, noise, at these levels, have been linked with health problems such as heart disease, high blood pressure and musculoskeletal problems. A Cornell University study on office noise, found that those working in noisy office environments can also be less likely to ergonomically adjust their workstations for comfort, contributing to other physical problems. Noise within the medium ranges can also impact sleep quality by preventing sleep and disrupting sleep cycles. And, perhaps most significantly, because chronic stress can lower your immunity to all disease, noise pollution is a general threat to employee wellness.
In the points below I have highlighted some of the key areas where even medium noise levels can have an adverse effect on general well-being and productivity within the workplace:
1. People will be less productive
A British Journal of Psychology study found that whether reading or writing, background noise will reduce productivity. In fact, experiments show that between the levels of 40 dB to 50 dB workers showed an astonishing 66% reduction in productivity.
Much has been said about open plan offices and its positive impact on moral and communication within the workplace. Collective noise within the medium levels does however remains a concern within these working environments and care must be given to ensure noise is managed in such work-spaces.
Dedicated quiet spaces, noise friendly flooring and sound friendly furniture, acoustic wall panels, cubicles and partitions, the occasional use of noise cancelling headphones are only some of the ways that noise can be reduced in open work offices.
Multitasking also becomes so much harder when strong background noise is present. With people using most of their energy to concentrate on the one thing in hand as a result of the surrounding influences.
2. Noise does cause workplace stress and reduces overall motivation
Scientists are in agreement that exposure to even medium noise levels stimulates our nervous system, raising blood pressure and releasing stress hormones. Workers are also less likely to concentrate on complex tasks following exposure to the same sounds.
Workplace experiments have shown that when medium level noises where introduced, workers recorded higher than normal epinephrine levels; a hormone associated with a spike in stress levels. Workers also displayed behavioural after effects, including fewer attempts at completing more challenging tasks.
3. An increase in office tension
Too much noise in an office can cause conflict and problems between employees.
Where talking is frequent and in a loud volume, whether on the phone, or to other colleagues. Other employees would have to raise their voices to talk over that person to be heard, this can create a vortex of noise, causing an array of distraction and frustration within the workplace.
4. A reduction in workplace creativity
In a study at the University of Illinois, participants were asked to work on a creative challenge while listening to one of several levels of noise loudness. They were told to come up with as many unique uses for a brick as they could imagine (doorstop, hammer, table centerpiece, and so on). When they had to brainstorm while listening to medium noise levels (at around 50 Decibels), they tended to be less creative than when they worked on the challenge with no noise at all.
As the noise level increased, participants had more difficulty thinking. And the harder it was to think, the more abstract their ideas became.
5. Noise effects learning
A study in Germany found that the actual average noise volume in school classrooms is 65 decibels contrary to the WHO recommendation of a maximum of 35 decibels. This would generally cause a reduction in speech intelligibility (a measure of how comprehensible speech is), meaning that not all that is said is being fully heard.
Where health and safety practitioners are concerned, looking beyond traditional practices, as well as controlling and minimising high levels of noise at the workplace, efforts should look at the health implication caused by consistent medium levels of workplace noise.
Although perception of noise level is only one of the many concerns in office design, the benefits of an open plan which encourages informal exchange of ideas, are often jeopardized by noise and distraction. How to design open space work areas that have an acceptable noise level which also encourage productivity is somewhat a challenge for health and safety practitioners and other business stakeholders alike.