SPL Meter

When doing some research on a SPL meter, you will sooner or later come across one or some of the SPL meter terms and abbreviations defined below:

SPL meter frequency weighting
In the specifications of nearly any SPL meter, you will find the term “frequency weighting”. Your SPL meter will either measure sounds with an A, C or Z frequency weighting. An A weighting applies when the sound measured by the SPL meter is audible by humans without any technical amplification, e. g. on a construction site or near an airport. When your SPL meter measures sounds with a C weighting, you can expect the SPL meter to measure sounds audible by the human ear, not naturally, but after an increase of the volume with technical help. The Z weighting includes sounds of a flat frequency response between 10Hz and 20 kHz ±1.5dB. Most international standards will require companies to use an SPL meter capable of measuring A-weighted noises. PCE Instruments offer a wide range of SPL meters with A frequency weighting.

SPL meter Leq

Some SPL meters from PCE Instruments can also calculate the Leq. One example is the PCE-322A SPL meter with a special software. The equivalent continuous sound level, which is the time-averaged sound level value measured by a SPL meter, is commonly abbreviated Leq.

SPL meter TWA

In connection with an SPL meter, TWA stands for the time-weighted average which describes the amount of noise a worker, for example on a construction site or in an industrial setting, is exposed to on a daily basis, assuming that he or she works 8 hours per day. The parameters a SPL meter needs to calculate the TWA are the average level of noise in a certain area and the time the worker spends there. This might be important for someone who is looking for a SPL meter for occupational safety. Some SPL meters show the noise dose throughout an 8-hour exposure in %.

SPL meter with octave band filter / third octave band filter

These terms can be helpful when trying to compare sounds coming from different sources, measured by a SPL meter. Noises measured by the SPL meter are broken down into their components, expressed in Hz, a unit of frequency. These values are very important when it comes to finding the right ear protection which often depends on the frequencies. An octave band is a frequency band where the lowest frequency is half of the highest one whereas a third octave band is 1/3 as wide as the octave band. This concept might not be easy to understand straightaway but is definitely worth considering when looking for a SPL meter to protect your workers from noise pollution.

A few questions to consider when looking for a SPL meter

- What material should my SPL meter be made of (depends on application / environment)?
- Am I looking for a hand-held SPL meter or for a SPL meter for fixed installation?
- Who will use my SPL meter (ease of use / large keys if protective gloves are worn)?
- Should my SPL meter have a large display (readability from a distance)?
- Does my SPL meter need to fulfil any standards (ISO, …)?
- How frequently will my SPL meter be used?
- Will my SPL meter be used continuously (battery life)?
- What additional parameters should my SPL meter measure (temperature, …)?
- What additional parameters should my SPL calculate (TWA, Leq, …)?
- What additional parameters should my SPL meter show (time, date, …)?
- Does my SPL meter need to have a memory?
- Would it be helpful if the SPL came with an evaluation software?
- Will I need technical support on my SPL meter?
- How many people will need to use the SPL meter at the same time (several SPL meters might be an option)?
- What requirements does my SPL meter need to fulfil to fit my existing pool of equipment?

Nowadays it is near to impossible to find a place in a town or city where there would be an absolute and total silence. Too much traffic, too many people, factories, plants, railway stations, airports and so on – from the one side, life is unimaginable without all these things, from the other – life may turn into torture, if they get out of control and do not meet any requirements. Outdoor noise or sound – is one of the stress causing factors and that is why the permissible level of the sound emission is under permanent control by a spl meter. Any equipment used outside (vehicles, devices, machinery) should meet the requirements of the EU directive concerning noise and outdoor equipment. Especially when it goes about living districts, there are particular time periods when the works by means of the drills and other noisy equipment, can be carried out. Even though these sounds are transient and do not last permanently, their level is extremely high for a normal unprotected human ear and that is why is strictly regulated and must measured by a spl meter. Problems with noise level are also experienced by those who live in the proximity to the railway stations, airports, noisy streets or even hospitals and police stations. Excessive and long-term exposure to high-level noise may have dramatic negative impacts on the human health (hearing damage, raised nervousness and irritability, unstable phycological condition), and in some areas noise monitoring and control by use a spl meter is an essential task! Thus, noise level of 120-150 dB /decibel (airport noise, planes taking off and landing, road drills) is absolutely dangerous to the human beings and that is why continuous presence or living very close to the sources of such kinds of noise may have consequences. The perfect level of 30-50 decibels, which is quite a favorable atmosphere with the sounds of a more quire and pleasant character, is sometimes not reachable any more.

To understand how bad the noise really is just by description of your physical perception is impossible - You have to use a spl meter. Different people percept noise in different ways, and what is perfect for some people, is unbearable for the others. Therefore, the limits of noise exposure have been set based not on individual opinions, but on scientific conclusions concerning healthcare. It applies to all people who are exposed to noise, not depending on their personal preferences: workers operating drilling equipment and similar should wear protective clothes, airports should mostly be built outside the living areas, the sirens should be adjusted to an acceptable level and many other similar points.

That is why a special spl meter has been created: ……… allows not only measuring and, thus, monitoring the environment “noise pollution” permanently, but enables to carry out the necessary changes, either in planning, or in already existing processes, for improving the surrounding atmosphere.This spl meter is weather proof, which means that is can be used even under harsh environmental weather conditions and the measuring process will not be interrupted. Since the measurements are to be carried out outside, near the airports or construction sites, a long-lasting battery pack is provided and there is no need to search for a power source when measuring on site. The possibility of mounting the spl meter on a tripod provided makes the measuring process easy and convenient and there is no necessity to hold the spl meter. The readings collected after a certain period of time may be processed and an absolutely clear picture of the noise level in a particular area / region is received.

It is necessary to remember that there are noise limits, for both, its level, as well as for its duration. The measurements received with the help of the spl meter show discrepancy between the desirable and real values and thus, any problem connected with the noise emission can be solved in a correct way, so that all the requirements were met and the working process (construction, airport, vehicles with sirens) was not stopped anyways.