Pressure, Vacuum and Ultrasonic Metrology Section

Objective: Pressure, vacuum and ultrasonic metrology are the key metrological fields for industry, research and society because of their extremely wide range of applications in industrial processing, manufacturing, testing, medical science, environment monitoring, aviation, aerospace, road transport, fundamental research, semiconductors, coatings, displays production, fusion experiments, biotechnologies, autofrettage, engine development, water jet cutting machines, food production and sterilisation, development of automated systems require traceable measurement of extremely low or extremely high pressures, or measurements under dynamic conditions.

The main aim of the Pressure, Vacuum and Ultrasonic Metrology Section is to realize, maintain and disseminate the derived SI unit of pressure and vacuum – the pascal (Pa). The Group has been providing apex level calibrations in pressure, vacuum and ultrasonic measurements and maintains traceability of pressure and vacuum measurements at international level. The main objective and activities of the group are to establish, maintain and upgrade national primary and secondary standards of pressure, vacuum and ultrasonic measurements equivalent to international standards through continuous research and development. Over the years the group has achieved the global status of compatible measurement standards and calibration facilities.



1. Calibration facilities Available

  • Vacuum standards:

    Calibration of different types of vacuum gauges, air and vacuum piston gauges /dead weight testers / pressure balances and various types of gauges such as Quartz Bourdon, Pirani, thermocouple, Penning, dial type, ionization, spinning rotor, capacitance diaphragm, inductive diaphragm, blood pressure measuring instruments in static conditions etc.

  • Pressure Standards:

    Calibration of piston gauges / dead weight testers / pressure balances, dial gauges, transducers, pressure transmitters (in absolute, gauge and differential modes), etc.

  • Ultrasonic Standards:

    Calibration and Testing of ultrasonicpower, equipments such as, ultrasonic transducers (angle, normal, focused beam, therapeutic), UFD, ultrasonic reference blocks (V1, V2 and step wedge), thickness gauge and reference rails. Also available are the facilities for ultrasonic velocity, impedance and attenuation measurements

2. Consultancy services

  • Characterization of vacuum / air / pneumatic / hydraulic piston gauges/dead weight tester/pressure balances.
  • Setting up of calibration laboratories for pressure, vacuum and ultrasonic measurements.
  • Reference standards for calibration of blood pressure measuring instruments in static conditions.
  • Characterization of ultrasonic transducers, ultrasonic power and NDT.
  • Development of customized systems/ instruments with improved parameters.

3. Training Services

Training programs in pressure, vacuum and ultrasonic metrology for various Indian industries, legal metrology officers, other users and international institutions.

4. International Acceptance

CSIR-NPL is a signatory to Mutual Recognition Arrangement (MRA) of International Committee of Weights and Measure (CIPM), France [1}. The CIPM MRA is the framework through which National Metrology Institutes demonstrate the international equivalence of their measurement standards and the calibration and measurement certificates they issue [2]. The outcomes of the Arrangement are the internationally recognized (peer-reviewed and approved) Calibration and Measurement Capabilities (CMCs) of the participating institutes. Approved CMCs and supporting technical data are publicly available from the CIPM MRA database (the KCDB) [2-3]. Therefore, most of the calibration services provided by Pressure, Vacuum and Ultrasonic Metrology Section of CSIR-NPL, are globally compatible, acceptable and available at very competitive rates [4]. We ensure timely, effective and customers’ friendly services.

5. References

Table – 1: List of Measurement Standards and Facilities Available
Instruments Range
Vacuum Standards - Barometric Region Ultrasonic Interferometer Manometer (UIM) – Primary Standard

1 Pa to 130 kPa

Air Piston Gauge – Primary Standard

6.5 KPa to 350 kPa

Forced Balanced Piston Gauge

1 Pa to 15 kPa

DPI – 145 – Secondary Standard

100 kPa, 130 kPa, and 400 kPa

Capacitance Diaphragm Gauge – Secondary Standards

13 kPa and 0.13 kPa

Static Expansion - Primary Standard

1000 Pa to 10-4 Pa

Orifice Flow Standard - Primary Standard

0.1 Pa to 10-6 Pa

SRG - Transfer Standard

1 Pa to 10-4 Pa

Spinning Rotor Gauge - Transfer Standard

10-3 Pa to 10-5 Pa

Ionization gauge - Transfer standard

0.1 Pa to 10-6 Pa

Extractor gauge - Transfer Standard

10-2 Pa to 10-6 Pa

Pressure standards - Pneumatic Region

Large Diameter Piston Gauge – Primary Standards

0.1 MPa to 1 MPa
1.0 MPa to 10 MPa

Ruska (USA) model # 2465 - Secondary Standards

1.4kPa to105 kPa
10 kPa to 4 MPa

Ruska (USA) model # 2470 - Secondary Standards

10 kPa to 12 MPa

Desgranges Et Huot (France) model # 5502- Secondary Standards
Differential Dual Piston Gauge

0.4MPa to 8MPa
0.8 MPa to 20MPa
0.8MPa to 40 MPa

Digital Pressure Transducers

0.1 MPa to 4 MPa
0.2 MPa to 10MPa

Pressure standards - Hydraulic Region

Controlled Clearance Piston Gauges – Primary Standards

  1. NPLH1
  2. NPLH2
  3. NPLH3

20 MPa to 1 GPa
10 MPa to 200MPa
5 MPa to 500 MPa

Ruska (USA) model # 2450 - Secondary Standards

0.07 MPa to 28 MPa
0.24 MPa to 140 MPa
0.48 MPa to 280 MPa

Desgranges Et Huot (France) model # 5306 - Secondary Standards
Differential Dual Piston Gauge

0.1 MPa to 10 MPa
0.04 MPa to 20 MPa
0.1 MPa to 50 MPa
0.2 MPa to 100 MPa
0.2 MPa to 100 MPa
0.4 MPa to 200 MPa
1.0 MPa to 500 MPa
1.0 MPa to 500 MPa
0.1 to 50 MPa
(For both as line and static pressures)

Digital Pressure Standards

0 MPa to 100 MPa
0MPa to 200 MPa

Ultrasonic standards

Radiation Force Balance based primary standard for ultrasonic
power measurements

1mW to 20 W
1 MHz to 20 MHz

EMAT based non-contact NDT Testing of conducting materials

4 MHz

C-Scan system for immersion NDT

Flow, cracks and internal defects detection

Ultrasonic facilities for measurement of propagation velocity,
impedance and attenuation

For solids and liquids

Contact Details

Dr. Sanjay Yadav,
Senior Principal Scientist and Head,
Pressure Vacuum and Ultrasonic Metrology Section
CSIR-National Physical Laboratory (CSIR-NPL)
Dr. K. S. Krishnan Marg, New Delhi – 110012, INDIA.
Phone : +91-11-47091206
Fax : 91-11-45609310