How Many Decibels is Really Safe at Work?

How Many Decibels is Really Safe at Work?


Our sense of hearing is a window to the world, enriching our lives and keeping us safe. Yet, in today's industrial and technological landscape, constant exposure to loud noises poses a significant threat to this precious sense. 

This is particularly true for those who work in environments dominated by the roar of machinery, the whine of power tools, or the cacophony of construction sites.

Fortunately, 3M also has solutions to help you reduce the impact of noise on your hearing. Learn more on how to protect your ears here!

Decibels and Safe Listening

Sound is a form of energy that travels in waves. The intensity of these waves is measured in units called decibels (dB). The higher the decibel level, the louder the sound. Here's a breakdown of decibel levels and their impact on our hearing:

  • Below 70 dB: Sounds at this level are generally safe for prolonged exposure. Imagine the gentle hum of a refrigerator, the rustling of leaves in a breeze, or a quiet conversation in a library.
  • 70-85 dB: This range includes sounds like normal conversation in a restaurant, traffic noise, or a hair dryer. While not immediately harmful, prolonged exposure at these levels can lead to hearing fatigue.
  • 85 dB: This is the recommended maximum decibel level for an 8-hour workday according to the National Institute for Occupational Safety and Health (NIOSH). Exposure above this level can cause hearing loss over time. Think of the noise from a busy street, a lawnmower, or a food processor.

Duration and Intensity of Sound Exposure

Unfortunately, our ears don't have an "off" switch for loud noises. The amount of safe sound exposure depends on the decibel level. Every 3 dB increase above 85 dB cuts the safe listening time in half. 

Here's an example: Imagine a battery representing your safe listening time. Louder noises (higher decibels) drain the battery faster, while quieter environments allow it to recharge.

For example, at 85 dB, you can safely work for an entire 8-hour shift. However, if the noise level increases to 88 dB, the safe duration drops to 4 hours. At 91 dB, it's only 2 hours, and so on. 

This highlights the importance of minimizing exposure to loud noises and taking breaks in quieter areas whenever possible.

Do You Know How Loud is Too Loud? 

Here's a quick reference to gauge how loud everyday sounds can be and how they stack up against safe listening levels:

  • 30 dB: Whisper
  • 60 dB: Normal conversation
  • 80 dB: City traffic
  • 85 dB: Hair dryer, food processor
  • 90 dB: Subway train, motorcycle engine
  • 95 dB: Lawnmower, noisy restaurant
  • 100 dB: Power tools, chainsaw
  • 110 dB: Rock concert, car horn
  • 120 dB: Threshold of pain, fireworks
  • 140 dB: Threshold of discomfort, gunshot

Sounds exceeding 120 dB can cause immediate damage to your ears, including temporary or even permanent hearing loss.

Common Dangerous Workplace Noises

Many workplace noises can inflict hearing damage if left unchecked. Here are some of the most common offenders:

  • Construction equipment: Hammers, drills, saws, and other machinery can generate noise levels exceeding 100 dB.
  • Manufacturing machinery: Factories often house equipment that produces sustained loud noises, putting workers at risk.
  • Generators: The constant hum of generators can contribute to hearing loss over time.
  • Power tools: Drills, sanders, and other power tools can reach decibel levels exceeding 90 dB.
  • Loud music: In restaurants, bars, or entertainment venues, exposure to amplified music can be particularly damaging.

The Three Pillars of Hearing Conservation

The severity of hearing loss depends on three main factors:

  1. Decibel level: As discussed earlier, louder noises cause more damage.
  2. Duration of exposure: The longer you're exposed to loud noises, the greater the risk of hearing loss.
  3. Frequency of exposure: Repeated exposure to loud noises, even for short periods, can be more detrimental than a single long exposure. Imagine repeatedly draining your hearing battery versus one long drain – both eventually deplete your safe listening time.

Got more questions about hearing protection? We've got a free white paper for you!