Acoustic Calibration Centre

A HOKLAS-accredited Acoustics Laboratory in HK

       The Acoustic Calibration Centre (ACC302) has been accredited by Hong Kong Accreditation Service (HKAS) under the Hong Kong Laboratory Accreditation Scheme (HOKLAS) since 2021. The ACC is the only laboratory HOKLAS-accredited to conduct real-time one-third octave band analyser test. We provide calibration services for sound level meterscalibrators and real-time one third octave band analyzer with HOKLAS Certificate of CalibrationSee HOKLAS 302 here for Scope of Accreditation.

Accredited Calibration Services

Sound Level Meter

       Verification of sound level meter in accordance with IEC 61672-3:2013 Cl. 11.2, 13, 14, 15, 16, 17, 18, 19, 20 and 21 for parameters against the relevant requirements as specified in IEC 61672-1:2013.

  • Self-generated noise with microphone replaced by the electrical input signal device
  • Electrical signal tests of frequency weightings
  • Frequency and time weightings at 1 kHz
  • Long-term Stability
  • Level linearity on the reference level range
  • Level linearity including the level range control
  • Toneburst response
  • C-weighted peak sound level
  • Overload indication
  • High-level stability

Sound Calibrator

Calibration of the sound pressure level, frequency accuracy, total distortion at 94dB or 114dB.

Real-time one third octave band analyzer

Verification of real-time one third octave band analyzer for parameters against the relevant requirements as specified in IEC 61260:1995.

  • Attenuation in the pass-band
  • Attenuation outside the pass-band

Contact us for details on prices and delivery times. We recommend that you contact us before sending equipment to us to keep the time you’re without your equipment at a minimum. 

Global Acoustic Calibration Alliance (GACA)


       The Norsonic Calibration Laboratory (NCL) is an accredited laboratory (Norwegian Accreditation No. CAL 022) in accordance to NS-EN ISO/IEC 17025 for calibration of sound and vibration measuring instruments and sensors such as measuring microphones, sound calibratorssound level metersaccelerometerstapping machines and reference sound sources.

       The calibration laboratory works on many makes and models of equipment, offering a swift turn around without compromising on accuracy.

Norwegian Accreditation is one of the signatories to the EA Multilateral Agreement for mutual recognition of calibration certificates (European Co-operation for Accreditation). The accreditation states that the laboratory meets the requirements concerning competence and calibration system for all the calibrations contained in the accreditation.

Further details about our accreditation scope and the accreditation certificate is found here.


       Acoustic Laboratory Thailand cooperated with the accredited Norsonic Calibration Laboratory in Norway and set up the ‘Norsonic Calibration Laboratory Asia’ in 2014 in cooperation with Geonoise Thailand.

  • You can send any brand of microphones, sound calibrators, sound measuring instruments, and accelerometers to us for calibration whenever needed. 
  • Calibration contracts to ensure calibration on regular basis are also available.
  • Material testing is done with the impedance tube (Kundt’s tube).
  • If you need a verifiable STC values we will measure it in our 2 decoupled reverberation rooms. Sound power measurements will be performed in the anechoic room.
  • In the reverberation rooms, we can also perform sound absorption measurements complying with ISO 354.

Hong Kong

Acoustic Calibration Centre (ACC) has been accredited by Hong Kong Accreditation Service (HKAS) under the Hong Kong Laboratory Accreditation Scheme (HOKLAS) since 2021.