Work area noise levels

Where employees are likely to be exposed to noise levels at or above the lower exposure action value, the employer must ensure that a noise survey is carried out by a competent person (reg. 4). Records of this assessment must be kept (reg. 5). In some cases the level of noise to which an employee is exposed varies considerably over the duration of a shift making it difficult to assess the exposme from a single or a few spot measurements. The use of a dosimeter will enable a single figure to be derived for a shift. The dosimeter is worn with the microphone close to the ear for the period of the shift and the results either read directly from the instrument or downloaded to a computer. When using the dosimeter it is important that the wearer works to his or her normal pattern and does not spend longer than normal periods in a noisy environment. Where a noise risk has been identified there is a requirement on the employer to reduce the emission to the lowest reasonably practicable level (reg. 6). 

If it is not reasonably practicable to reduce noise exposure levels to below the lower exposure action value of 80dBALEPd then the employer is 

All hearing protection equipment must be kept in good order (reg. 8) and employees are required to use properly and look after any personal protective equipment issued to them. Considerable emphasis is placed on keeping employees informed (reg. 10) of  

This is a very brief summary of some of the provisions of the legislation and it is strongly recommended that the actual regulations are studied. There are also a number of very useful advisory publications available from HSE Books (see Further References and Reading). 

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Environmentally Responsive Work-stations (ERWs). Workers in open-office areas have direct, individual control over both the temperature and air-flow. Radiant heaters and vents are built directly into their furniture and are controlled by a panel on their desks, which also provides direct control of task lighting and of white noise levels (to mask out nearby noises). A motion sensor in each ERW turns it off when the worker leaves the space, and brings it back on when he or she returns. 

Fermenters can be located outdoors in most countries ofthe world. The working platforms usually are enclosed and heated in temperate zones, and only shaded in more tropical zones. In more populated areas, open fermenter buildings make too much noise for local residents. The environmental awareness, or the tolerance of the public, could preclude open fermenter buildings in the friture. Odor is also offensive to the public. The environmental authorities are demanding that equipment be installed to eliminate the offensive odor ofthe off-gases. (Noise levels inside a fermenter building will be greater than 90 dBA if no preventive measures are taken.)... 

Noise levels are very difficult to reduce to Federal standards. Hearing protection for employees is essential. The move towards greater automation has resulted in operators having less exposure to noisy work areas. 

A major advantage of computer technology over the typewriter is less noise at the workstation. However, it is not unusual for computer users to complain of bothersome office noise, particularly from office conversation. Noise levels commonly encountered in offices are below established limits that could cause damage to hearing (i.e., below 85 dBA). The JES (1996) proposed that the noise level should not exceed 55 dBA. The expectations of office employees are for quiet work areas because their tasks often require concentration. Annoying noise can disrupt their ability to concentrate and may produce stress. 

Construction employees who engage in abrasive blasting are at an increased risk of exposure to toxic dusts, high noise levels, and a range of other safety and health hazards. See the handout for a list of hazards. Co-workers may also be at risk if they work in the vicinity of areas where abrasive blasting is conducted. 

Place the compressor as far as possible from the work area to reduce the level of noise. 

Do employees move between separate work areas with different noise levels ... 

Are the size or shape of rooms and proposed layout of equipment, work stations, and break areas to be evaluated for noise levels ... 

Noise hazard area Any area where noise levels are equal to or exceed 85 dBA. OSHA requires employers to designate such work areas as such, post warning signs, and warn employees when work practices exceed 90 dBA. Hearing protection must be worn whenever a level of 90 dBA is reached or exceeded. 

Have work areas where noise levels make voice communication between employees difficult been... 

Noise levels not only change over time, they also vary in different areas of the facility — often so widely that different hearing protection is required for various work areas or, occasionally, various tasks in the same work area. Recognize noisy spots and periodically take readings in these problem areas. Repeat monitoring whenever a change in production, process, equipment or controls increases noise exposures to the extent that additional employees may be exposed or hearing protection device attenuation is inadequate. At a minimum, conduct annual assessments — or even more frequent assessments in previously identified noisy spots. ... 

If the noise level in your work area is too high, your employer must take additional action to reduce that noise. Steps to reduce noise might include ... 

In general, the emitted noise level of vertical machines is much lower than horizontal machines due to less vibrating surface exposed to the work area. 

Orientation and location - moving the noise source away from the work area, or turning the machine around. Much can be done to reduce site perimeter noise levels by careful positioning of noisy fixed plant, and by screening plant using sound baffles and earth banks. 

Isolation of workers in acoustically-quiet booths or control areas properly enclosed, coupled with scheduling of work periods to reduce dose. This will only be effective where there is little or no need for constant movement into or out of areas with high noise levels even a short duration exposure to high sound pressure levels will exceed the permitted daily dose. Nevertheless, improved design of vehicle and plant cabs and (for example) batch plant and lifting equipment operating positions can do much to improve the health of operators. 

Machine layout should be planned to provide safe access and clear working area for machinists. COSHH assessments must be available for all hazardous materials used, including wood dusts. Noise assessments should be available for all machines and processes where action levels are exceeded. 

The impact of high noise levels drops off quickly the further a person is from the noise source. Therefore, when making decisions about the control of noise, it is important to determine where the workers are likely to be located. One company states that a work area is any position in which a person may be present and which is no less than 1 meter from equipment surfaces, or any position where a worker s ear may be exposed to noise in the normal course of his duty. It includes platforms, walkways, and ladders. 

Noise Level in Work Area (dBA) Maximum Distance/Required Voice Effort (m) ... 

A combination of ear plugs and ear muffs offers greater noise protection and may be appropriate for employees such as turbine mechanics who work at high-noise-level areas for long periods of time. 

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