Sound power testing - ISO 3741 - iso 3744

Sound power and sound pressure are different ways to quantify sound. Sound power is a measure of sound energy from a source, regardless of the location or surroundings. It is a function of the device, not the environment or distance. Sound pressure results from a noise source's power and the effect of its environment, including the distance from the source to the receiver. 

WHICH DO I NEED?

Sound Power

Generally speaking, if you are quantifying the noise of a device for regulatory conformity, labeling, or engineering purposes, you will probably want to determine the sound power. Consultants and engineers can use sound power data to calculate the resulting sound pressure from sources in different locations and under various conditions. For instance, an HVAC engineer or consultant can calculate the mechanical noise criteria in a room from the power ratings at the HVAC unit's inlet, discharge, and case. The sound power - along with details of the duct system and room properties - is used to calculate sound pressure under certain conditions. 

Sound Pressure

If you are quantifying the amount of noise present in a space or in an environment, you are looking for a sound pressure measurement. Community noise and architectural noise criteria or NC, are based on sound pressure measurements.

Clear as mud? If you're unsure, call us (612) 355-1277; we'll help you determine your needs. North Orbit can measure each of these and more in our laboratory or on location.

You provide the testing goals and we devise an efficient test plan and cost proposal. Your goals may be to comply with a regulatory standard, find a marketing advantage over a competitor, or investigate a product based on customer inquiries. You are encouraged to witness the testing of your products so that you can enjoy the added benefit of consulting directly with our seasoned acoustical experts. The results are shared in real-time as we complete tests, providing insight into your products and allowing for R&D adjustments on subsequent tests. You will receive a test summary detailing all the results of the test. Data is further analyzed, and if requested, a formal test report is generated. 

TESTING METHODS

NOAL can determine sound power and pressure levels under a wide range of conditions and circumstances to satisfy many purposes. The following list is just a sampling. Let us know what you’re looking for and odds are that we can do it!

ISO 3741: Determination of sound power levels and sound energy levels of noise sources using sound pressure — Precision methods for reverberation test rooms

ISO 3741 (ANSI/ASA S12.51) is a standard developed by the International Organization for Standardization (ISO) for measuring and evaluating the sound power level of sources in a specific environment: A specially qualified reverberation test chamber. ISO 3741 is a way to measure and assess the strength of sound emitted from a source, such as a machine, computer, medical device, component, or consumer product. The standard provides guidelines for precisely conducting laboratory tests. Users can compare the results to specified limits or label their devices for regulatory purposes. Acousticians can use the data in models to make decisions about controlling or reducing unwanted noise indoors. outdoors, or in specific acoustical environments.

ISO 3744 (ANSI/ASA S12.54) Determination of sound power levels and sound energy levels of noise sources using sound pressure – Engineering methods for an essentially free field over a

reflecting plane

ISO 3744 is a standard developed by the International Organization for Standardization (ISO) for measuring and evaluating the sound power level of sources in a specific environment: An essentially free field, typically our hemi-anechoic test chamber. ISO 3744 is a way to measure and assess the strength of sound emitted from a source, such as a machine, computer, medical device, component, or consumer product. The standard provides guidelines for precisely conducting laboratory tests. Users can compare the results to specified limits or label their devices for regulatory purposes. Acousticians can use the data in models to make decisions about controlling or reducing unwanted noise indoors, outdoors, or in specific acoustical environments.

ISO 9614 (ANSI/ASA S12.54) Determination of sound power levels using sound intensity

AHRI 230 Sound Intensity Testing Procedures for Determining Sound Power of HVAC Equipment

ISO 9614 is a standard developed by the International Organization for Standardization (ISO) for measuring and evaluating the sound power level of sources in any typical environment. ISO 9614 is a way to measure and assess the strength of sound emitted from a source, such as a machine, computer, medical device, component, or consumer product. The standard provides guidelines for precisely conducting tests using very specialized sound intensity measuring instruments and software and can be done in the laboratory or in situ. The ability to do tests in-situ is unique to this engineering grade method. Users can compare the results to specified limits or label their devices for regulatory purposes. Acousticians can use the data in models to make decisions about controlling or reducing unwanted noise indoors, outdoors, or in specific acoustical environments.

ISO 60601-1-8 Meaurement of alarm systems in medical equipment

ANSI S1.13 Measurement of sound pressure levels in air

ANSI S12.2 Criteria for evaluating room noise (Noise Criteria / NC)

ISO 11200 Noise emitted by machinery and equipment — Guidelines for the use of basic standards for the determination of emission sound pressure levels at a work station and at other specified positions

ISO 11201 Noise emitted by machinery and equipment — Determination of emission sound pressure levels at a work station and at other specified positions in an essentially free field over a reflecting plane with negligible environmental corrections

ISO 11202 Noise emitted by machinery and equipment — Determination of emission sound pressure levels at a work station and at other specified positions applying approximate environmental corrections

ISO 11203 Noise emitted by machinery and equipment - Determination of emission sound pressure levels at a work station and at other specified positions from the sound power level

ISO 11204 Determination of emission sound pressure levels at a work station and at other specified positions applying accurate environmental corrections

MIL-STD-1474 Department of defense design criteria standard noise limits 

MIL-STD-740 Airborne and structure-borne noise measurements and acceptance criteria of shipboard equipment