Overview
IEC 61672-2:2013 is an internationally recognized standard published by the International Electrotechnical Commission (IEC) that defines the pattern evaluation tests for sound level meters used in electroacoustics. As Part 2 of the IEC 61672 series, this standard specifies the necessary tests to ensure sound level meters comply with the mandatory performance specifications outlined in IEC 61672-1. It applies to time-weighting, integrating-averaging, and integrating sound level meters, including both Class 1 and Class 2 categories.
This standard focuses on harmonizing laboratory testing procedures globally to guarantee consistent and reliable acoustic measurements. The 2013 revision, with 2017 amendments, updated test criteria to incorporate measurement uncertainty limits with a 95% coverage probability, improving confidence in conformity assessments. The standard covers multi-channel meter evaluation and various environmental and electroacoustic performance factors.
Key Topics
- Conformance Testing: Verification that sound level meters meet design goals within specific acceptance limits, with measurement uncertainty accounted for.
- Pattern Evaluation Tests: Includes directional response, frequency weighting accuracy, level linearity, self-generated noise, and overload indication for each channel of multi-channel meters.
- Environmental Testing: Assessing meter performance under varying conditions such as air temperature, relative humidity, static pressure, electrostatic discharges, and radio-frequency interference.
- Calibration and Marking: Requirements for sound level meter marking and instruction manuals to facilitate compliance and traceability.
- Measurement Uncertainty: Emphasizes the importance of uncertainty analysis in all tests to ensure a high confidence level of 95%.
- Electroacoustic Performance: Detailed methods for testing frequency weightings using acoustic and electrical signals, toneburst response, and corrections for environmental influences.
- Electrical and Radio-Frequency Tests: Evaluates susceptibility to power-frequency fields, radio-frequency emissions, and the effect of public power supply disturbances.
- Reporting: Standardized format for presenting pattern evaluation test results to support certification and quality assurance.
Applications
IEC 61672-2:2013 is critical for manufacturers, testing laboratories, and regulatory bodies involved in the development, certification, and deployment of sound level meters. Its practical applications include:
- Product Certification: Ensuring new sound level meters comply with international specifications before market release.
- Quality Control: Enabling manufacturers to verify the acoustic performance and environmental robustness of their devices.
- Legal Metrology: Supporting regulatory agencies in confirming that sound measurement instruments meet legal requirements for environmental noise monitoring and occupational health.
- Acoustic Research and Development: Providing a standardized testing framework to develop precise and reliable sound measurement instruments.
- Multi-Channel System Validation: Testing sound level meters designed for complex applications requiring simultaneous multi-channel measurements.
- Maintenance and Calibration Labs: Assisting in routine verification of sound level meters to maintain measurement accuracy over time.
Related Standards
- IEC 61672-1: Defines the specifications for sound level meters including performance requirements and measurement methods.
- IEC 61672-3: Addresses periodic testing procedures to maintain compliance after initial certification.
- OIML R 16: International recommendation for sound level meter performance, harmonized with IEC standards.
- IEC 60651 / IEC 60804: Earlier standards for sound level meter specifications, referenced for historical context.
- ISO 1996 Series: Standards for describing and measuring environmental noise, often used alongside IEC 61672.
- IEC 61000 Series: Standards on electromagnetic compatibility (EMC) relevant to radio-frequency and power disturbance tests mentioned in IEC 61672-2.
IEC 61672-2:2013 is essential for ensuring consistent, accurate, and reliable sound measurement worldwide. By standardizing pattern evaluation tests, it promotes high-quality acoustic instrumentation for noise control, health, safety, and environmental monitoring applications. Manufacturers and test laboratories benefit from clarity in testing protocols and robust criteria for performance, helping safeguard sound level meter integrity in diverse conditions.
