​The Physical and Electrical Metrology Division plays an important role in the South African economy by developing and maintaining National Measurement Standards and Reference Standards for a vast number of measurement parameters. We aim to deliver world-class measurement products and client services.

Our goal is to continually improve our measurement standards and techniques. We are driven by advances in science and technology and an ever-greater industrial demand for measurement accuracy. With our calibration and measurement services we support industry and research by providing reliable and accurate measurements and measurement solutions.

Correct measurements are vital for reliable and efficient manufacturing of products, as well as for safety, health and fair trade. With our advanced measurement systems and techniques, we ensure the traceability of all the measurement parameters we maintain to the International System of Units (the SI). In order to keep up with the ever-increasing pace of development we are constantly developing and refining our measurement capabilities, and to this end conduct various research and development projects. Divisional staff includes experts in a range of measurement parameters and is committed to maximizing impact by collaborations with industry, government, and university stakeholders.

National Measurement Standards (NMS) and Reference Standards

The SI system is founded on seven (7) SI base quantities assumed to be mutually independent as shown in the table below. All other quantities are derived quantities, which may be written in terms of the base quantities by the equations of physics.

The Physical and Electrical Metrology Division maintains measurement parameters that address six (6) of the seven (7) SI base units, namely;

• the metre,

• the kilogram,

• the second,

• the candela,

• the ampere and

• the kelvin.

Of these six (6) SI base units, the Division realises five (5) of the SI base units, namely;

• the metre,

• the kilogram,

• the second,

• the candela and

• the kelvin.

NMISA derives traceability of the ampere (A) from voltage (V) and resistance (Ω). Voltage is realised using a Josephson Voltage Standard, while traceability of resistance is imported from a selected NMI with the appropriate Calibration Measurement Capabilities (CMCs) in the BIPM key comparison database. The international equivalence of all National Measurement Standards and reference standards is maintained by regular participation in key and regional comparisons and the maintenance of CMCs in the BIPM key comparison database.