Calibration Services
The Acoustic Test Facility provides a unique range of calibration and measurement services to meet the individual measurement needs of the user. ATF, NIOT currently provides the following underwater acoustic calibration and testing services as per IEC 60565-1,2020
- Free-field calibration of hydrophones by the reciprocity method from1 kHz to 500 kHz.
- Free-field calibration of underwater acoustic transducers and hydrophones by comparison method from 1 kHz to 500 kHz.
- Calibration of hydrophones by the vibrating water column method from100 Hz to 1 kHz
- Directional response measurement of hydrophones and transducers in the frequency range up to 500 kHz over 360 degrees of rotation with 1 degree resolution.
- Transducer electrical impedance in the frequency range 100Hz to 1MHz.
- Power and source level linearity measurement of transducers.
- Sound pressure level measurement and frequency analysis.
Accreditation Details
This facility is accredited for calibration and testing of underwater acoustic transducers in the year 2005 by National Accreditation Board for Testing and Calibration Laboratories (NABL) and the accreditation is continued by periodical surveillance and re-certification as per ISO/IEC 17025:2017. Measurements are performed in accordance with IEC 60565-1, 2020 in the frequency range from 100Hz to 500 kHz.
ATF QUALITY POLICY"Acoustic Test Facility (ATF) of National Institute of Ocean Technology (NIOT) is committed to maintain good professional practice to provide accurate and consistent results to the customer for testing / calibration of underwater acoustic transducers/ parameters in accordance with the International Standards.
All the laboratory personnel shall be well trained and familiar with the documentation to implement the policies and procedures. Each member of the staff shall be responsible for providing timely and reliable services to the customer's requirement.
ATF is committed to fulfil the requirements of quality management system and continually improve its effectiveness in line with the ISO/IEC 17025:2017."
Inter-Laboratory Comparison
Inter-Laboratory Comparison of hydrophone calibration has been successfully completed for the frequency range for the frequency range from 3kHz to 500kHz with the following International institutes and it is observed that the results of DOE (Degrees of Equivalence) are in very good agreement for entire frequency band.
- Bundeswehr Technical Centre for Ships and Naval Weapons, Naval Technology and Research, WTD 71, Germany.
- Federal State Unitary Enterprise "Russian Metrological Institute of Technical Physics and Radio Engineering" (FSUE "VNIIFTRI"), Russia.
The ILC results establish that the hydrophone calibration at NIOT conforms with the International standards and on par with the internationally acclaimed laboratories.