The AFNOR/S30D commission is concerned with issues of acoustics at work. It aims to characterize, measure and evaluate noise in the workplace. The commission ensures the implementation of standards, both in their design and in their application. It develops documents in the field of office noise (and associated premises) and defends the French position on the subject in international standardization bodies.
What are the issues related with noise at work?
Thomas Bonzom: This is a vast subject, which is not new! The interest in this topic goes back several years, because of the strong industrialisation that existed in France. The factories generated a very important noise level. Today, the industrial landscape has evolved but noise levels remain very high in the construction and metallurgy industries, for example. And the problem has shifted: it now also concerns office environments and primarily open spaces.
What are the risks associated with noise at work?
TB: Hearing problems are logically the main risk to be considered. From 80 decibels (db), a sound exposure of 8 hours (i.e. a working day) generates a first danger of deafness.
But other risks can occur such as stress, fatigue, cardiovascular diseases or digestive disorders… They are part of the “extra-auditory” effects of noise, i.e. those which do not directly affect hearing. And they can appear well before the 80 db threshold, whether in an office, in the field of education or in the restaurant business.
Noise at work also affects productivity. In a noisy office, lack of concentration and loss of time impact the efficiency of employees.
What do studies say about the consequences of noise at work?
TB: The ADEME report on the social cost of noise in France estimates that noise at work represents 5.3 billion euros per year. These costs are related to lost productivity and adverse health effects.
A 2015 survey shows that 93% of employees feel annoyed by noise in the office. The same study found that about 80% of employees feel that their work environment makes it difficult for them to concentrate.
The National Institute for Research and Safety (INRS) is also very interested in acoustics in the workplace. The institute has conducted a large study to identify the main disturbances:
- intelligible conversational noise, i.e. conversations that colleagues understand clearly, without having to concentrate;
- unintelligible conversational noise, which refers to conversations that colleagues do not understand and which are closer to background noise;
- the flow of people and the noise of machines, telephones or elevators.
How do you protect yourself from noise at work?
TB: Treating the ceiling is a prerequisite! Limiting the sound reverberation in the room helps to reduce the noise in the space. For example, every open space should have a class A or B ceiling (according to the classification of ceilings and acoustic systems in the ISO 11654 standard). The most classic is the false ceiling with acoustic tiles. But there are also other suspended systems, such as islands.
On the floor, there are fewer solutions. Of course, carpeting is the most effective, but its level of absorption remains average. It does, however, reduce the sound of heels or walking in the aisles.
What are the recommended solutions and best practices?
TB: The first step is to look at the activities of the people who work in the open space and understand their needs. Some people need to communicate with each other from their workstations, but others need to concentrate or make phone calls in quiet.
In coworking, users perform completely different activities. One solution is to offer different types of dedicated spaces: some for those with a need to communicate, and others for coworkers who require more privacy. The installation of partitions, which rise above the head, allows to reduce intelligibility and thus to be less disturbed by conversations of the office neighbors.
Do we need to control user behavior?
TB: The behavioral aspects are still very difficult to control, but rules can be set. In a coworking space, users tend to self-regulate. So it’s a good idea to remember a few things, like avoiding conversations at the workstation and preferring other spaces for informal discussions. It is also not possible to impose the use of personal protective devices on coworkers. However, they can be the beginning of an answer. A German study has just been published on the use of noise-reducing headphones in open spaces. If the performance of the workers is not improved thanks to these equipments, they notably reduce the feeling of discomfort.
