Exposure to too loud sounds for too long at work, when doing leisure activities or when listening to music can harm your hearing and cause permanent hearing loss and tinnitus.
Therefore, an initiative of The World Health Organization (WHO), the “Make Listening Safe workgroup” is committed to creating a world where nobody’s hearing is put in danger due to unsafe listening.
Today, there is a clear consensus that 85 dBA average exposure for eight hours per day leads to irreversible noise induced hearing loss.
For the availability of hearing protection at work, for personal music players and personal amplifiers, the maximum exposure should be under the average of 80 dBA for 40 hours.
Personal sound amplifiers that don’t have the capacity to measure the weekly dose of sound exposure need to be permanently limited to 95 dBA. Setting a maximum output level is however not advisable since this can result in higher compression in the source music file or in the amplification.
The population is at risk
Standards for safe listening in the industry, for personal music players and for personal amplifiers are very important to avoid hearing loss and other hearing damages. For each of the three areas the World Health Organization, estimates that the population is at risk:
- Worldwide, 16% of the disabling hearing loss in adults is attributed to occupational noise.
- Worldwide 1.1 billion teenagers and young adults are at risk of hearing loss due to the unsafe use of personal audio devices and exposure to damaging levels of sound at noisy entertainment venues.
- Worldwide, there are 466 million persons with disabling hearing loss (6.1% of the world's population).
The “Make Listening Safe workgroup” is an initiative of The World Health Organization in the framework of the World Hearing Forum. The initiative is committed to creating a world where nobody’s hearing is put in danger due to unsafe listening.
Overview of standards
From 1971 onwards, many standards have been published on noise exposure in the industry:
- In 1971 the International Standards Organisation published the ISO 1999 - Standard on “Acoustics — Assessment of occupational noise exposure for hearing conservation purposes”: (the risk of noise induced hearing loss significantly increases from an exposure of 85 dBA Lex8h/day and higher.)
- In 1972, the first American NIOSH (National Institute for Occupational Safety and Health) guidelines were published. (no worker exposure shall equal or exceed” is displayed, exposure level 85dBA – 8 hours)
- In 2003, the European Commission publishes the EU Noise at Work Regulations (Directive 2003/10/EC) with 3 exposure action values 80 dB(A), where hearing protectors need to be available, 85 dB(A), where individual hearing protection shall be used, and 87 dB(A), which is the absolute exposure limit.
After the standards for noise exposure at work, from 2010 onwards new standards has also developed to ensure safe listening with personal audio systems.
- In 2010 the International Technical Commission (ITC) published the first standard IEC 62368-1 on Audio/video. (The output level of the personal music player, for an output that stays under or equal to 85 dBA, is considered safe and the LAeq,T acoustic output shall be lower or equal to a sound output value of 100 dBA).
- In 2018 the new ITU and WHO standard H.870 “Guidelines for safe listening devices/systems”, was published. (The weekly sound dose, of headphones and earphones associated with personal music players, should be limited to the equivalent of 75 or 80 dBA for 80 hours/week).
- Since October 2019, you can find this feature, the weekly dose of sound exposure, in the health app on iPhone. We hope that many smartphone and headphone manufacturers will follow soon.
The most recent standards on Safe Listening are related to Personal Sound Amplifiers.
In 2017 the Consumer Technology Association, published the ANSI/CTA standard 2051 on “Personal Sound Amplification Performance Criteria”. (The maximum OSPL90 output level shall not exceed 120 dB SPL measured in a 2cc coupler)
In 2019 ITU published ITU-T H.871, which describes safety requirements for personal sound amplifiers (PSA) :
- For PSA’s with the capacity to measure weekly dose it is required that weekly maximum sound dose needs to be less than 80 dBA for 40 hours.
- When PSA’s do not have the capacity to measure weekly sound dose, the maximum output of the device needs to be permanently limited to 95 dBA
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