A noise study involves taking measurements of noise across the entire facility or a particular area to determine areas that are noisy. The purpose of a survey is to determine whether employees are exposed to noise levels in the workplace that exceed the limits for exposure set under the laws (in the UK The Control of Noise at Work Regulations 2005) or the limits that are set by the business. It is important to note that the UK is not the only country to do this regard and that many nations have developed standards for workplaces for ensuring that the standard degree at which employees are exposed over the course of an eight-hour day is not more than 85dB(A).
Why should you conduct the noise survey?
The noise survey can provide valuable data that allows a safety professional to determine:
Locations where employees are most at risk of being exposed hazardous levels of noise
Equipment and machines that produce dangerous levels of noise
Operatives who may be exposed to unacceptably loud levels
The survey is best carried out in an area where noise is likely cause harm, such as the example of shops or assembly lines. Most of the time the survey will require taking measurements of noise levels using the aid of a sound level gauge. The readings of noise levels are taken at a favourable range of locations within the noise zone. A noise map may be constructed using lines drawn on a sketch of points with the same sound level These maps can provide valuable information, allowing you to clearly identify zones that pose risks from noise.
What is involved in an investigation of noise?
Noise can be measured with an instrument for measuring sound levels that measures SPLs (SPLs) at dB(A) as well as the maximum noise level attained, also known as the sound pressure at its peak measured in Pascal (Pa).
There are two main kinds of sound meter: directly and in-built reading meters. Meters that combine the readings offer an average over a specific amount of time. This is an important method to use when there are significant variations in the levels of sound. This is referred to in the form of the constant equivalent noise, or Leq, which is usually determined or normalized over an 8-hour period.
The sound level gauge, or in fact any noise measurement device, has to be calibrated prior to and following every measurement session. To measure the sound level meter must be placed at arm’s length from the height of your ear for those who are exposed to loudness. Make sure you take measurements for each ear!
In assessing the possibility of hearing loss, the microphone’s position must have the closest distance it is close to the ears of the person to benefit from the data on noise exposure is being collected. If a worker is stationary the microphone must be placed over the shoulders, or at least as close as it is feasible. If the worker is in a standing posture the microphone must be placed at least 1.5 meters over the ground. If the employee is sitting the microphone must be set at least 1 centimetres higher than the floor.
In workplaces with high or intermittent noise levels (but even in the cases when workers’ movements aren’t monitored or accompanied) The noise level meter was not intended to measure an individual’s exposure to noise throughout the whole or even a part of their shift. One option is to utilize a noise dosemeter , also referred to by the name of a Personal Sound Exposure Meter (PSEM) that is worn on the shoulders of the person being monitored and record the noise exposure and then, statistically, determines the noise exposure over similar exposure levels. The noise dosemeter can be used for a short period of time or over a couple of days, depending on the consistency of jobs performed every day. In this scenario it is not necessary to have the person who is responsible for measuring the noise to be present. Noise data is gathered and downloaded to be analysed at the conclusion of the measurement time.
