Noise action and limit values

Noise does not affect just the hearing organs, but also many physiological functions of the body, such as heart rate, blood pressure and respiratory rate. Noise can also be generally disruptive and affect concentration and sleep. In the so-called “noise regulation” laid down in the Finnish law, action limit values have been set for different levels of even noise and impulse noise occurring at work. The evaluation of noise exposure is mainly based on a daily dose.

Lower exposure action value

•  80 dB(A), assessed without hearing protection
• peak value for the sound pressure level of impulse noise is 135 dB(C)

The employer must provide the worker with personal hearing protection. The employee is also entitled to take a hearing test.

Upper exposure action value

• 85 dB(A), assessed without hearing protection
• peak value for the sound pressure level of impulse noise is 137 dB(C)

The worker must wear hearing protection. Dangerous areas for noise must be marked, and access to these areas must be restricted when necessary. The employer must also draw up a noise prevention programme.

Limit value

• 87 dB(A), assessed with hearing protection
• peak value for the sound pressure level of impulse noise is 140 dB(C)

The employer must take measures to reduce the exposure below the limit value.

Noise prevention in the workplace 

Noise exposure in the workplace can be reduced by encasing machines, sing partition screens and silencing devices, and adding sound- absorbing material to the walls and ceilings. In noise protection, it is important to pay attention to the noise level of the equipment already when purchasing them.

Noise exposure in the workplace can be reduced by encasing machines, using partition screens and silencing devices, and adding sound- absorbing material to the walls and ceilings. In noise protection, it is important to pay attention to the noise level of the equipment already when purchasing them.

Hearing protection

During an 8-hour working day, the noise level inside the hearing protectors should be from 75 to 79 dB. Hearing protectors that dampen
the noise too effectively may cause problems in oral communication.

Noise prevention programme

• find out why the limit values are exceeded
• set targets for reducing noise exposure
• examine the technical prevention measures that are related to the
  organization of work and are targeted towards the source of the noise.

The noise prevention programme can be a part of the of the occupational safety and health policy.

Disturbing noise

The annoyance of the sound environment depends more on situational factors than the physical properties of the noise. Situational factors include the level of concentration required by the work, mood, fatigue and external pressure. Individual characteristics also affect the annoyance of the noise, such as sensitivity to noise, hearing loss or tension. Noises that people find the most distracting are speech, phone ringtones and walking in the hallways. Machine and traffic noise are perceived as being less annoying.

Good acoustics for open spaces

• sound absorption in ceilings and walls
• tall screens (170cm) with glass tops
• textile carpets
• soundproofing and location of passageways and break rooms
• soundproofed retreat rooms and phone booths
• a large open space is better than several small ones
• office etiquette.

Etiquette for common open spaces

• use of the spaces in different situations (work tasks, breaks)
• keeping workstations tidy and organized
• communication in the work community
• use of the radio, telephone and vocal media
• movement in the workspace
• communications regarding work duties that require concentration.

Vibration action and limit values

Occupational diseases caused by vibration have decreased significantly thanks to automation and machinery product development. Typical symptoms of hand-arm vibration include white finger, numbness of the fingers and reduced grip strength. Whole-body vibration can cause symptoms in the lower back. In the so-called “vibration regulation” laid down in the Finnish law, the action value for hand-arm vibration is defined as 2.5 m/s², and the action value for whole-body vibration is 0.5 m/s². The limit value is 5 m/s² for hand-arm vibration and 1.15 m/s² for whole-body vibration. If the exposure exceeds the action value, the employer must draw up a vibration prevention programme, which is essentially similar to the noise prevention program. If the exposure exceeds the limit value, immediate action must be taken to reduce the exposure below the limit value. The limit value can be temporarily exceeded if the exposure varies considerably between different work phases.

Source: The center for occupational safety; Helsinki, Finland

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There are five major elements to sound reduction. One of the most effective one’s being Absorption. We will talk about the other four approaches to soundproofing in next blogs to come. It common for people to confuse “Absorption” concept of soundproofing and acoustic treatment with Sound Absorbing Panels. “Absorption” is installation of insulation between walls, ceilings or floors which reduces the resonating frequency in the cavity. 

Acoustic treatment by installation of Sound Absorbing Panels also involves installation of sound absorbing materials, but is a quite different process. Instead of hitting a hard surface, therefore creating noise and echo, the sound is being absorbed by the panel. Our acoustic panel is made of high-quality materials: wooden frame, high noise absorbing insulation and a fabric of your choice. Mind, that the less hard surfaces there are in the specific place the less sound will be absorbed.

Two major soundproofing problems have to be taken into consideration when designing acoustic treatments. First one is to improve the sound quality inside the room. Secondly to reduce the sound leakage between adjacent rooms or outdoors. Acoustic quieting and noise control are two ways limit unwanted noise. The goal is to suppress intrusive indirect sound waves such as reflections that cause echoes and resonances. 

Whatever the issue is We recommend You call us and request our Sound Consultation Service. During the consultation, we will be able to assess most of the sources for unwanted sound waves, sound leakage and reflections that bounce from point to point generating echo. Soundproofing can be made very simple, but needs differ from client’s needs. Contact now to find out yours.

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Noise is intense, disturbing and unpleasant sound. Excessive noise can cause hearing impairment. Noise that contains sudden, powerful impact sounds, so-called impulse noise, is particularly harmful. Noise is the most common cause for occupational diseases. People can find even low noise levels disturbing when e.g. doing work that requires concentration in open-plan offices. What a person experiences as noise is up to the individual. Harmful vibrations are body vibrations transferred from a tool to one’s hand, or whole-body vibrations transferred from a platform, for example a working machine’s seat, to the person.

Noise action and limit values

Noise does not affect just the hearing organs, but also many physiological functions of the body, such as heart rate, blood pressure and respiratory rate. Noise can also be generally disruptive and affect concentration and sleep. In the so-called “noise regulation” laid down in the Finnish law, action limit values have been set for different levels of even noise and impulse noise occurring at work. The evaluation of noise exposure is mainly based on a daily dose.

Lower exposure action value

•  80 dB(A), assessed without hearing protection
• peak value for the sound pressure level of impulse noise is 135 dB(C)

The employer must provide the worker with personal hearing protection. The employee is also entitled to take a hearing test.

Upper exposure action value

• 85 dB(A), assessed without hearing protection
• peak value for the sound pressure level of impulse noise is 137 dB(C)

The worker must wear hearing protection. Dangerous areas for noise must be marked, and access to these areas must be restricted when necessary. The employer must also draw up a noise prevention programme.

Limit value

• 87 dB(A), assessed with hearing protection
• peak value for the sound pressure level of impulse noise is 140 dB(C)

The employer must take measures to reduce the exposure below the limit value.

Noise prevention in the workplace 

Noise exposure in the workplace can be reduced by encasing machines, sing partition screens and silencing devices, and adding sound- absorbing material to the walls and ceilings. In noise protection, it is important to pay attention to the noise level of the equipment already when purchasing them.

Noise exposure in the workplace can be reduced by encasing machines, using partition screens and silencing devices, and adding sound- absorbing material to the walls and ceilings. In noise protection, it is important to pay attention to the noise level of the equipment already when purchasing them.

Hearing protection

During an 8-hour working day, the noise level inside the hearing protectors should be from 75 to 79 dB. Hearing protectors that dampen
the noise too effectively may cause problems in oral communication.

Noise prevention programme

• find out why the limit values are exceeded
• set targets for reducing noise exposure
• examine the technical prevention measures that are related to the
  organization of work and are targeted towards the source of the noise.

The noise prevention programme can be a part of the of the occupational safety and health policy.

Disturbing noise

The annoyance of the sound environment depends more on situational factors than the physical properties of the noise. Situational factors include the level of concentration required by the work, mood, fatigue and external pressure. Individual characteristics also affect the annoyance of the noise, such as sensitivity to noise, hearing loss or tension. Noises that people find the most distracting are speech, phone ringtones and walking in the hallways. Machine and traffic noise are perceived as being less annoying.

Good acoustics for open spaces

• sound absorption in ceilings and walls
• tall screens (170cm) with glass tops
• textile carpets
• soundproofing and location of passageways and break rooms
• soundproofed retreat rooms and phone booths
• a large open space is better than several small ones
• office etiquette.

Etiquette for common open spaces

• use of the spaces in different situations (work tasks, breaks)
• keeping workstations tidy and organized
• communication in the work community
• use of the radio, telephone and vocal media
• movement in the workspace
• communications regarding work duties that require concentration.

Vibration action and limit values

Occupational diseases caused by vibration have decreased significantly thanks to automation and machinery product development. Typical symptoms of hand-arm vibration include white finger, numbness of the fingers and reduced grip strength. Whole-body vibration can cause symptoms in the lower back. In the so-called “vibration regulation” laid down in the Finnish law, the action value for hand-arm vibration is defined as 2.5 m/s², and the action value for whole-body vibration is 0.5 m/s². The limit value is 5 m/s² for hand-arm vibration and 1.15 m/s² for whole-body vibration. If the exposure exceeds the action value, the employer must draw up a vibration prevention programme, which is essentially similar to the noise prevention program. If the exposure exceeds the limit value, immediate action must be taken to reduce the exposure below the limit value. The limit value can be temporarily exceeded if the exposure varies considerably between different work phases.

Source: The center for occupational safety; Helsinki, Finland

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