Acoustic Calibrators

What is an acoustic calibrator?

An acoustic calibrator is a precision instrument that is used to verify the accuracy of sound level meters, microphones, and other sound-measuring devices. It provides a reference sound level, usually at a specific frequency, which can be used to calibrate and validate the accuracy of the measurement equipment. An acoustic calibrator is an indispensable tool for anyone working in the field of sound and vibration measurement, providing a reference for calibrating the equipment and ensuring accurate and consistent measurements.

These devices are a critical component in ensuring accurate and reliable sound measurements, which can have a significant impact on workplace health and safety. To ensure that sound measurement is accurate, it is crucial to use an acoustic calibrator that is traceable to national and international standards, has a high degree of accuracy and stability, and is regularly calibrated.

How do acoustic calibrators work?

Acoustic calibrators work by providing a known reference sound level for calibrating sound level meters, personal noise dosimeters, microphones, and other acoustic measurement equipment. They emit a precisely calibrated sound wave, typically at a specific frequency and sound pressure level, which is used as a reference for the equipment being calibrated. The acoustic measurement equipment is placed in close proximity to the acoustic calibrator and its readings are compared to the reference sound level emitted by the calibrator. This comparison allows the user to determine if the equipment is functioning correctly and if any adjustments are needed to ensure accurate measurements.

Acoustic calibrators typically come in the form of hand-held devices or as built-in calibrators in larger measurement systems. They play an essential role in ensuring the accuracy and consistency of sound measurements in various industries, including occupational health and safety, environmental noise monitoring, and more.

What are the types of acoustic calibrators?

There are several types of acoustic calibrators, each designed for specific measurement applications and requirements. Some of the most common types include:

Pistonphone calibrators: These are handheld devices that generate a known sound pressure level using a piston-driven mechanism. They are commonly used for calibrating microphones and other sound level meters.
Sound level meter calibrators: These are specifically designed to calibrate sound level meters and are typically used in conjunction with a pistonphone calibrator.

Electro-acoustic calibrators: These devices generate a known sound pressure level using an electrical signal, and are commonly used to calibrate microphones, sound level meters, and other acoustic measurement equipment.

Electro-dynamic calibrators: These are similar to electro-acoustic calibrators, but use a speaker-like mechanism to generate the known sound pressure level. They are commonly used to calibrate microphones and other sound level meters.

Combination calibrators: These devices combine several types of calibrators into one unit, making it easier to calibrate multiple types of acoustic measurement equipment.

Each type of acoustic calibrator has its own set of advantages and disadvantages, and the choice of calibrator will depend on the specific needs of the user and the application for which it is being used.

The type of acoustic calibrator you need will depend on your specific measurement requirements, such as frequency range, accuracy, and measurement environment. It is important to choose a calibrator that is designed for your specific measurement application to ensure accurate and reliable results.

What is the IEC classification for acoustic calibrators and what do the different classes represent?

The International Electrotechnical Commission (IEC) has established a classification system for acoustic calibrators to ensure the accuracy and reliability of sound measurement equipment. This classification system ranges from Class 0 to Class 4, with Class 0 being the highest level of accuracy and Class 4 being the lowest.

Class 0 calibrators are highly accurate and are used for laboratory calibrations and other applications requiring the highest level of accuracy. Class 1 calibrators are suitable for field calibrations and applications that require a high level of accuracy, but not as high as Class 0. Class 2 calibrators are used for routine field calibrations and for general-purpose sound level meter calibrations.

Class 3 calibrators are used for rough checking of sound level meter performance and for basic maintenance purposes. Class 4 calibrators are used for rough checks of sound level meter performance and are not recommended for use in applications where accurate sound measurements are required.

It is important to choose an acoustic calibrator that meets the accuracy requirements of your specific application, as using a calibrator that is not appropriate for your needs can result in inaccurate sound measurements.
What is the purpose of using an acoustic calibrator in occupational health?
The purpose of using an acoustic calibrator in occupational health is to ensure that sound level meters and other acoustic measurement equipment are accurately calibrated and provide consistent and reliable readings. This is important in occupational health settings because workers are often exposed to hazardous noise levels in their work environment, and accurate measurement of these levels is critical for determining the need for hearing protection and other preventive measures. Using an acoustic calibrator helps to verify the accuracy of the measurement equipment, providing confidence that the readings are correct and that workers are properly protected from hazardous noise levels. In addition, regular calibration with an acoustic calibrator helps to maintain the accuracy of the measurement equipment over time, reducing the risk of measurement errors and ensuring the validity of the data collected.

How do I know if my acoustic calibrator is accurate?

To determine the accuracy of an acoustic calibrator, it is necessary to calibrate it using a known standard. This can be done by comparing the output of the calibrator to a reference standard, such as a primary standard or transfer standard. The calibrator should be checked against the reference standard over a range of frequencies and sound pressure levels to determine if it is accurate within the desired tolerance.

That’s why it is recommended to use a calibrator from a reputable manufacturer and to purchase calibrators that meet relevant standards, such as those from the National Institute of Standards and Technology (NIST) or the International Organization for Standardization (ISO). These standards ensure that the calibrators are manufactured to a certain level of accuracy and quality

How often should an acoustic calibrator be calibrated?

The frequency of calibrating an acoustic calibrator depends on several factors, including the manufacturer’s recommendations, the intended use, and the environment in which it will be used. Typically, it is recommended to calibrate acoustic calibrators at least once a year, or more frequently if they are used frequently or in harsh environments. Additionally, if an acoustic calibrator shows any signs of being damaged or if its readings seem to be inaccurate, it should be calibrated as soon as possible. It is important to follow the manufacturer’s recommendations and guidelines for calibrating your acoustic calibrator to ensure its accuracy and reliability over time.

Which acoustic calibrator should I buy?

When selecting an acoustic calibrator for occupational health applications, there are several key factors to consider to ensure that the device meets your specific needs and requirements.

Accuracy: Ensure that the calibrator provides accurate and reliable sound level measurements and that it is calibrated to the appropriate standards.

Frequency range: Consider the frequency range that you need to calibrate for your specific applications. Some calibrators may only cover a limited range of frequencies, while others may cover a wider range.

Calibration procedures: Verify that the calibrator includes an easy-to-use calibration procedure and that it provides a clear and accurate reference sound level.

Durability: Consider the durability of the calibrator and ensure that it can withstand the demands of the occupational health environment.

Ease of use: Ensure that the calibrator is easy to use and that it provides clear and concise instructions for calibration and operation.
Size and weight: Consider the size and weight of the calibrator, especially if you need to transport it frequently.

Reputation: Look for a well-established brand with a good reputation for quality and customer support.

Technical support: Ensure that the manufacturer provides local technical support and that they can answer any questions you may have about the calibrator.

By considering these key factors, you can select the best acoustic calibrator for your occupational health applications and ensure that you have the necessary tools to accurately measure sound levels and protect workers’ hearing health.

Svantek Models

Svantek offers a range of acoustic calibrators for Class 1 and Class 2 sound level meters and dosimeters with 1/2 microphones. These calibrators provide a defined acoustic pressure at a specified frequency, ensuring accurate and consistent sound level measurements. The SV 33B, SV 34B and SV 36 calibrators all feature robust housing, microprocessor-controlled signal sources, digital static pressure and temperature compensation, and automatic adjustment for varying ambient conditions. They meet IEC 60942: 2017 standards, have a specified tolerance and are powered by AAA batteries. Each calibrator comes with a statement of calibration to ensure the user can have confidence in their accurate measurements.

SV 33A

The SV 33A Class 1 Acoustic Calibrator is a top-of-the-line device designed to provide precise and accurate calibrations for Class 1 and Class 2 sound level meters and dosimeters with 1/2 microphones. This calibrator produces a defined acoustic pressure of 114 dB at 1 kHz, ensuring that sound level measurements are accurate and consistent.

The SV 33A features robust housing for a comfortable and secure grip, as well as a microprocessor-controlled signal source with digital static pressure and temperature compensation for excellent stability in a wide range of ambient temperatures and humidity levels. This calibrator operates with AAA batteries and does not require any adjustments by the user. Each calibrator is also provided with a statement of calibration for added confidence in accurate measurements. With a tolerance of +/- 0.3 dB SPL and +/- 0.2% in frequency, the SV 33A Class 1 Acoustic Calibrator is a reliable and trusted tool for professionals in the field of occupational health and metrology.

SV 34A

The SV 34A Class 2 Acoustic Calibrator is a reliable and accurate tool for calibrating Class 2 sound level meters and noise dosimeters with 1/2 microphones. The calibrator generates a reference signal of 114 dB at 1 kHz and is designed with robust housing for a secure grip. The calibrator also compensates automatically for temperature and humidity changes, making it an ideal choice for a variety of applications. Additionally, the use of MEMS technology provides the best price-performance ratio in the current noise market. The SV 34A meets IEC 60942: 2003 standards and has a tolerance of +/- 0.5 dB SPL and +/- 0.2% in frequency. The built-in static pressure and temperature compensator ensure accurate readings, even in varying conditions. The calibrator operates using AAA batteries and is suitable for use within a temperature range of 0°C to +40°C

SV 36A

The SV 36 Acoustic Calibrator is a compact and highly portable Class 1 sound source device. This device is powered by two LR03/AAA batteries and features a loudspeaker that produces an acoustic pressure of either 94 dB or 114 dB at a frequency of 1 kHz.

The calibrator is equipped with a reference piezoresistive sensor for monitoring the generated level, pressure and temperature sensors for measuring atmospheric conditions, and a microprocessor system that controls the operation of the calibrator. The 1 kHz frequency sinusoidal waveform is digitally generated and fed to the loudspeaker. The reference piezoresistive sensor samples the signal to indicate the current level of the generated signal in a feedback loop. The microprocessor system adjusts the amplification of the loudspeaker signal based on the level of the signal, actual pressure, and temperature values to ensure the correct sound pressure level in the calibrator’s chamber.

In accordance with IEC 60942: 2003, the SV 36 is a Class 1 Acoustic Calibrator that generates 114/94 dB signals at 1000 Hz. It has a tolerance of +/- 0.3 dB SPL and +/- 0.2% in frequency and is equipped with a built-in static pressure and temperature compensator. With a temperature range of -10°C to +50°C, the calibrator features automatic microphone detection and an automatic on/off function. It operates using AAA batteries.