Noise in the workplace: When is 85 dB one decibel too much?

As acousticians, we often see that noise in the workplace is downplayed until employees begin to complain about tinnitus or chronic fatigue. Below you will find hard data based on European directives and Polish law, without unnecessary "beating around the bush".

Noise standards in the workplace - hard numbers (NDN)

In the context of health and safety regulations and acoustics, a key concept is NDN, which stands for the Highest Permissible Intensity. Based on Directive 2003/10/EC of the European Parliament, which harmonizes regulations across all member states, noise standards in the workplace are strictly defined for three parameters:

1. Noise set at the daily exposure level (8h): The limit is 85 dB.

2. Maximum A-weighted sound level (LAmax): Must not exceed 115 dB.

3. Peak C-weighted sound level (LCpeak): Must not exceed 135 dB.

It's worth knowing that permissible noise standards in the workplace also provide for so-called "action thresholds." Already at 80 dB, the employer must ensure access to hearing protection, and at 85 dB, wearing them becomes mandatory, and the workplace must be marked accordingly.

Noise intensity in the workplace and your health

Why does the European Union approach these values so restrictively? Research from the European Agency for Safety and Health at Work (EU-OSHA) indicates that noise intensity in the workplace above 80 dB not only poses a risk of permanent hearing damage.

It is also a powerful systemic stressor. Even if noise at the workstation is not "painful," prolonged exposure raises cortisol levels, increases the risk of cardiovascular diseases, and drastically lowers concentration. In open space offices, where informational noise (conversations) predominates, the problem is not the decibels, but the intelligibility of speech, which distracts our attention.

Measuring noise in the workplace – how do we do it?

To determine whether the standards are exceeded, a professional noise measurement in the workplace is essential. As acousticians, we do not use mobile apps for this purpose (which often have an error margin of +/- 10 dB), but calibrated integrating sound level meters of class 1 or 2.

The procedure is as follows:

• We measure noise directly at the employee's ear (using dosimeters) or in the work area.

• We analyze noise in the work environment considering the duration of individual activities.

• We calculate LEX,8h - the average noise dose that an employee "takes in" throughout the entire shift.

What is noise? (A brief theory at the end)

Now that you know the limits and dangers, it is worth clarifying the fundamentals. The physical definition of noise is any sound of any acoustic character that is undesirable, harmful, or burdensome to health under given conditions.

Interestingly, from the perspective of psychoacoustics, even a quiet sound (e.g., dripping faucet or a squealing coil in a monitor) can be considered noise if it hinders concentration, even though occupational health and safety standards are not exceeded.

Remember: Hearing is a sense that has no "eyelid" - we cannot close it. Therefore, taking care of acoustics in the company is not only a legal obligation but also an investment in the team's efficiency.