top of page

EN 352 - Hearing protectors, general requirements

Standard DIN EN 352 regulates general requirements for hearing protection as part of protective workwear.

Selection of appropriate hearing protection in accordance with DIN EN 352 depends on the specific working conditions and the type of noise occurring at the workplace.

Requirements for hearing protection are regulated accordingly and classified into the following types:

  • Earplugs

  • Earmuffs

  • Hearing protection helmets

In addition to the general requirements in accordance with DIN EN 352, product-specific features and requirements are regulated in the following special standards.

In accordance with DIN EN 352, all hearing protectors must be marked with:

  • Manufacturer's name or trademark and model name

  • EN number

  • Instructions on insertion, application and wearing (as necessary)

  • Nominal size

  • CE marking

  • Indication of reusability or single use (relevant for earplugs)

  • Left or right marking (for otoplastics)

DIN EN 352-1

Moldex-M5-6120-High Quality Earmuffs

27 dB

Earmuffs in accordance with standard DIN EN 352-1 are defined as hearing protectors that enclose each of the wearer's external ears with a functional capsule. As it is often desirable to frequently put on and take off ear protection in areas with variable noise exposure, earmuffs are recommended for such environments.

DIN EN 352-2

Moldex-Twisters Trio-6451-Flanged Reusable Earplugs

33 dB

DIN EN 352-2 defines earplugs as all hearing protectors that are worn directly in the auditory canal or ear cavity.
According to the regulations, use of earplugs is recommended:

  • for continuous noise (lower frequencies)

  • when earmuffs tend to cause strong sweating

  • when also wearing safety spectacles

  • when wearing other protective equipment such as head protection or face protection

  • together with earmuffs for brief periods of extreme noise

While the general requirements for earplugs are regulated in DIN EN 352-2, part 7 describes the safety requirements and tests for level-dependent earplugs.

DIN EN 352-3
Earmuffs Attached to Industrial Safety Helmets

Moldex-MX 7-6140-Helmet Mounted Earmuffs

31 dB

Standard DIN EN 352-3 describes all earmuffs that are directly attached to industrial safety helmets.


SNR stands for or Simplified Noise Reduction or Single Number Rating. Simply put, it means how much noise the ear plugs or other

hearing protection attenuate.

The SNR score is calculated based on the average attenuation of different frequencies. It is a weighted average of all the high to low frequencies. For example, a grinding disc primarily makes noise at high frequencies. The rumble of a generator is primarily at low frequencies.

The higher the number, the more sound the hearing protection blocks. For example, hearing protection with an SNR score of 32 attenuates the sound by 32 decibels (dB). By using this hearing protection, the sound that reaches your ears is therefore 32 dB quieter.

What Is dB (A)?

dB(A) is the unit for the sound pressure level attuned to the sensitivity of the human ear.

The sensitivity of the human ear is not the same for all sound frequencies. That is why dB(A) is used for noise measurements instead of ordinary dB.

This table shows the maximum length of time you can be exposed to a certain sound pressure level without suffering damage.

Noise Level in dB (A)

Maximum Exposure

80 dB (A)
83 dB (A)
90 dB (A)
100 dB (A)

8 Hour
4 Hour
48 Minute
5 Minute


Be sure to check that your hearing protection meets the EN 352 standard. Choose the right SNR score that fits with the specific task.

Always protect yourself as well as possible. Choose the appropriate personal protective equipment. This way you will not only work safely, but also better and more comfortably.

  • Always choose hearing protection that meets the EN 352 standard

  • Earplugs must also be EN 352 certified

  • Choose the SNR score with adequate attenuation

  • Take the possible risks into account and use maximum protection

  • Always work comfortably and safely

bottom of page