Sound level meters are handheld electronic devices that take acoustic measurements. They provide readings on the noise level in an environment and usually return a measurement in decibels (dB). Sound level meters are also called decibel meters or noise meters.Most meters feature an integrated digital display and some have an inbuilt datalogging memory to store readings. Many models can be attached to a smartphone or tablet and the data easily shared. Some models need connecting to a computer to export data.What is the difference between Class 1 and Class 2?There are two classes of sound meter; Class 1 and Class 2 (also referred to as Type 1 or Type 2). Sound level meters are given a classification of I or II depending on which international standard they meet. Type 1 or Class 1 sound meters are used for incredibly precise noise measurements (such as in laboratories) as they are able to measure the smallest sound levels. Class 2 sound level meters are usually used in workplaces for assessing and measuring noise.What is weighting?Weighting refers to the frequency range that is measured. Some sound meters will only measure one frequency range, while other models are able to measure all.A frequency covers a 20 Hz to 20 kHZ range. However, the sound is cut from the lower and higher ends of the spectrum in order to approximate the frequency that is audible to the human ear.C frequency can measure much higher noise levels, but still covers the frequency heard by the human ear.Z frequency covers the whole frequency range between 10Hz to 20 kHZ, ±1.5dB.Should I calibrate my sound level meter?Considering a calibration service your sound level meter will ensure that it always returns the most accurate measurements. It provides you with absolute confidence that your instrument works as expected with the highest accuracy.What is a dosimeter?Sound level meters measure the noise within a whole environment whereas dosimeters measure personal exposure to noise. Dosimeters (or dosemeters) are typically attached to an individual at work to monitor noise levels.Why would I use a sound level meter?Sound level meters will give you measurements on the level of noise within an environment. High noise levels can damage hearing, cause hearing loss and can have a detrimental effect on health. With a reading from a sound meter, you can make sure that you have the correct measures in place (such as slowing down machinery to minimise excess noise) and appropriate PPE (Personal Protective Equipment) to minimise risk.