What is noise and how is it measured?
Noise is measured in decibels (dB) - a logarithmic scale used to describe sound intensity. This means that small increases in decibels represent large increases in sound energy.
For example:
A normal conversation is around
60 dB
Busy traffic can reach
80–85 dB
Power tools and machinery often exceed
90 dB
When does noise become dangerous?
As a general rule, noise above 85 dB can begin to damage hearing over time - particularly with prolonged exposure. In the UK, workplace noise is controlled by the Control of Noise at Work Regulations 2005, which set key thresholds:
- 80 dB (lower action level): Employers must provide information and training
- 85 dB (upper action level): Hearing protection must be provided
- 87 dB (exposure limit): Maximum legal exposure (with protection)
These limits highlight an important point: It’s not just how loud a sound is - it’s how long you’re exposed to it.
How long is too long?
Because decibels are logarithmic, every increase of 3 dB roughly doubles the sound energy, meaning safe exposure time is cut in half. For example:
- 85 dB → safe for ~8 hours
- 88 dB → ~4 hours
- 91 dB → ~2 hours
- 94 dB → ~1 hour
This is why even moderately loud environments can become hazardous over a full working day.
| 85 dB | City traffic | 8 hours | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| 88 dB | Bulldozer | 4 hours | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| 91 dB | Jazz concert | 2 hours | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| 94 dB | Lawn mower | 1 hour | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| 97 dB | Nightclub | 30 mins | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| 100 dB | Ambulance siren | 15 mins | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| 103 dB | Rock concert | 7.5 mins | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
No one wants to enjoy their favourite music festival for just 7.5 minutes! Make sure you are safe to enjoy the whole event by wearing correctly fitted earplugs from uvex.
Signs noise levels are too high
If you’re unsure whether a sound is dangerous, look for these signs:
- You have to raise your voice to speak to someone nearby
- Your ears feel uncomfortable or painful
- You experience ringing (tinnitus) after exposure
- Sounds seem muffled afterwards
These are early warning signs that noise levels may be too high.
Why noise matters in the workplace
Excessive noise doesn’t just affect hearing - it can also impact:
- Communication and situational awareness
- Concentration and productivity
- Stress and fatigue levels
Over time, repeated exposure to high noise levels can lead to permanent hearing damage or tinnitus, often without immediate warning signs.
How to protect your hearing
Managing noise risk follows a simple hierarchy:
- Reduce noise at source (quieter equipment, maintenance)
- Control exposure (limit time in noisy areas)
- Use hearing protection where required
Correctly selected hearing protection is essential - it should reduce noise to a safe level without overprotection, allowing users to remain aware of their surroundings.
So, how much noise is too much?
As a general guide, anything above 85 dB over time poses a risk to hearing.
The key is understanding both volume and exposure duration, and taking proactive steps to control noise before damage occurs. With the right knowledge and protection, noise-induced hearing loss is entirely preventable.
FAQ's
Noise above 85 dB is considered potentially harmful with prolonged exposure. Higher levels become dangerous much more quickly.
Around 85 dB is comparable to heavy traffic, a lawnmower, or busy industrial equipment.
Yes. Very loud sounds - especially above 100–120 dB - can cause damage even with short exposure.
- 80 dB: lower action level
- 85 dB: upper action level
- 87 dB: maximum exposure limit
If you need to raise your voice to speak to someone nearby, the noise level is likely 85 dB or higher.
No. Noise-induced hearing loss is permanent, but it is completely preventable with the right controls and protection.
It depends on the environment. The goal is to reduce noise to a safe level without blocking essential sounds, ensuring both protection and awareness.