Noise is unavoidable in various workplaces, especially in industries such as construction, manufacturing, and entertainment. However, loud noise at work can damage hearing, and every employer has a responsibility to ensure employee safety. The law also expects different companies to minimise noise to a level that can’t affect people in the neighbouring environments.
This safety measure makes it necessary for most workplaces to have a sound measuring device, whether to protect employees or simply avoid nuisance from neighbours. Today, we’ll look at the different classes of these devices to help you decide the best fit for your needs.
What is a Sound Level Meter?
A sound level meter is a device that measures sound pressure levels, typically expressed in decibels (dB). The device does this by capturing sound through a sensitive microphone and then translating this into numerical levels that show the intensity of the noise.
These devices come in handy when assessing and managing noise in various settings, whether at workplaces or near schools. They can help you quantify the noise levels your equipment produces to ensure compliance, and they can also help take protective measures from noisy environments such as busy streets.
Depending on the type of meter you use, you can measure basic noise levels or carry out detailed frequency analysis for more complex work environments.
The Major Classes of Sound Level Meters
International standards (IEC 61672) categorise sound level meters into Class 1 (or Type 1) and Class 2 (or Type 2). Generally, these classes depend on the level of accuracy and the environments they’re designed to operate in.
Class 1 Sound Level Meters
Class 1 includes the most accurate sound level meters. These are designed for professional and scientific applications and minimal accuracy variations (about ±1 dB) and a wide frequency range. This ensures they can be used across various environments, providing reliability and precision even when the noise levels are low (like in laboratories). They can also give accurate figures in environments where the noise levels fluctuate, such as when you are assessing traffic noise.
In terms of numbers, Class 1 sound level meters can work with a frequency range of 10 Hz to 20k Hz, with a measurement range of 20 dB to 140 dB.
Due to their precision and wide frequency range, these sound level meters are mostly used in lab testing, product development, audiology, occupational noise exposure assessment, and industries that need to ensure noise compliance.
Class 2 Sound Level Meters
Class 2 sound level meters are more practical and versatile than their Class 1 counterparts. They are more general-purpose with a wide range of applications, so they are suitable for routine noise monitoring tasks. However, they don’t have the accuracy (a variation of about ±1 dB) or wide frequency range of Type 1 sound level meters. In most cases, they range between 20 Hz to 8 kHz, with a decibel range of 30 dB to 130 dB.
Class 2 sound level meters are suitable for tasks such as workplace noise assessments, community noise checks, or simple sound level evaluations. They can also be used to ensure health compliance, and their affordability makes them more suitable for businesses and landlords.
How Should You Select the Right One?
Choosing between the two types generally depends on the environment in which you’ll be using the sound meter level. If it’s quiet environments like labs or situations where you need accurate measures such as product testing, Class 1 sound level meters are more suitable. They are also often required for legal noise assessments and professional sound work.
However, they come with a heavier budget. Class 2 meters are much cheaper, and they offer reliable results. They are more suitable for environments such as offices and schools.
Generally, if it’s professional work or regulatory compliance, go for Class 1. If it’s general-purpose sound measuring, Class 2 sound meter levels will do the job well.
