DASM is currently recognized as the leading organization in Vietnam for ASTM C423 sound absorption coefficient testing according to the international standard. It is also the first and only unit in Vietnam with an acoustics laboratory accredited with VILAS certification in the field of acoustics.
The importance of sound absorption coefficient testing in acoustics
In the field of acoustics and soundproofing materials, accurately determining the sound absorption coefficient is crucial. It plays a key role in acoustic design, assessing the performance of materials, and ensuring compliance with technical requirements in construction projects. Among the various international standards available, ASTM C423 is the most reputable and widely used for measuring sound absorption in reverberation rooms.
What is ASTM C423?
This is a standard developed by ASTM International (American Society for Testing and Materials), specifying the method for measuring sound absorption in a reverberation room. This method allows the determination of critical parameters such as:
- Octave Band Absorption Coefficients
- Noise Reduction Coefficient (NRC)
- Sound Absorption Average (SAA)
The ASTM C423 standard is commonly applied in:
- Acoustic design of theaters, conference halls, and factories
- Inspection and certification of sound-absorbing and sound-insulating material performance
- Documentation for bidding in construction projects
- Supporting export procedures for materials requiring sound absorption performance reports
What are the requirements to perform ASTM C423 testing?
To conduct a sound absorption test that meets the reverberation room testing standards, the following are essential:
🔹 An ISO 354-compliant reverberation chamber: A controlled environment that accurately simulates standard reverberation without interference from external noise or thermal fluctuations.
🔹 Multi-channel sound measurement equipment compliant with ANSI/IEC: Devices capable of precisely capturing and presenting acoustic data across the full frequency range.
🔹 Trained and experienced acoustic experts: Operators must understand the principles of sound measurement and know how to interpret acoustic data correctly.
🔹 Accredited laboratory: Only results from a facility certified under ISO/IEC 17025 are internationally recognized.
ASTM C423 sound absorption testing procedure
Sample preparation
▪ The material sample must meet the minimum surface area requirement (typically at least 6 m²)
▪ Installation must follow the standard method (either flat mount or random mount)
Initial room measurement
▪ Measure the background reverberation time in the empty room
First measurement (without sample)
▪ Record reverberation time in the unoccupied room
Second measurement (with sample)
▪ Record reverberation time with the material sample placed inside
Data analysis
▪ Calculate sound absorption coefficients at each frequency band according to the standard formula
▪ Determine the NRC and SAA as defined in ASTM C423
Why choose DASM for sound absorption testing?
🔥 VILAS-Certified acoustic laboratory
▪ DASM is the only organization in Vietnam accredited by VILAS (Vietnam Laboratory Accreditation Scheme) for materials acoustic testing in compliance with ISO/IEC 17025
🔥 State-of-the-art equipment
▪ Reverberation room built to ISO 354 standards, equipped with internationally certified measuring instruments
🔥 Experienced acoustic engineers
▪ Our expert team has conducted hundreds of acoustic material tests with professional precision
🔥 Internationally recognized results
▪ Our test data is valid for project acceptance, tender documentation, and export requirements
🔥 Trusted by major clients
▪ DASM has been trusted by leading manufacturers and construction firms including Remak, Vĩnh Hưng, and many acoustic material factories across Hanoi, Ho Chi Minh City, and other regions.
DASM is ready to provide consultation and testing services for clients interested in ASTM C423 sound absorption coefficient testing. With a strict testing process, modern equipment, and a team of experienced experts, we ensure accurate and internationally recognized results.
Contact DASM’s hotline today for expert consultation and a fast quotation.
