​​​​​​​​​​About

NMISA's Temperature & Humidity Section has internationally recognised expertise and facilities aimed at improving the practical measurement of temperature and humidity. We help establish and maintain the International Temperature Scale of 1990, ITS-90. For the safe and effective operation of industrial processes, accurate measurement of temperature and Humidity is crucial. We support industrial measurements through a wide range of activities including research, industrial partnerships, consultation, and training.

We support industrial measurements through a wide range of activities including research, industrial partnerships, consultation, and training. We offer calibrations against the South African National Standards that are validated through international co​mparisons. We provide cost-effective, impartial, quality assured solutions: from everyday measurements to those at the extremes of sensing technology, such as temperatures above 2000 °C, or humidity in an extreme range. We work with a variety of sectors including aerospace, manufacturing, space, medical and pharmaceutical​

Key Fac​​ts

The kelvin, unit of thermodynamic temperature, ​is defined by fixing the numerical value of the Boltzmann constant k to 1.380 649×10−23 J⋅K−1. This unit is equal to kg⋅m2⋅s−2⋅K−1

Relative humidity (RH) is a ratio, expressed in percent, of the amount of atmospheric moisture present relative to the amount that would be present if the air were saturated at the same temperature.​​

How we can help y​​ou

The Section offers measurement, calibration, training ​​and consultation services as listed below:

• Calibration of contact thermometers from -196 °C to 1555 °C:

• ​​platinum resistance thermometers (PRTs) can be calibrated from -196 °C to 660 °C.

• thermistors from 0 °C to 60 °C.

• thermocouples from -80 °C to 1555 °C and

• liquid-in-glass thermometers from -25 °C to 280 °C.

• ​​Calibration of infrared radiation thermometers from 0 °C to 1600 °C and blackbody radiation sources from 0 °C to 2000 °C.

• Traceability for contact thermometry is obtained from thermometric fixed point cells from the triple point of argon (Ar) (-189.344 2 °C) to the freezing p​oint of copper (1084.62 °C). (Pt-Rh thermocouples are calibrated at the melting point of palladium (1553.5 °C) using the wire-bridge method.

• Development of calibration methods and transfer traceability to industry and African NMIs.

• Dissemination of temperature scales by calibration of temperature sensors. 

• Provide a link between the African region and the rest of the world's NMIs through comparison measurements in temperature and humidity.
  

• Fixed points calibration of standard platinum resistance thermometers from Ar to Al points.
  

• Calibration of other contact thermometers in the temperature range from -80 °C to 1600 °C.
  

• Fixed point calibration of thermocouples in the temperature range from Sn to Pd points.
  

• Calibration of surface thermometers in the temperature range from 0 °C to 450 °C.
  

• Calibration of radiation thermometers and blackbody radiation sources from 0 °C to 2000 °C.
  

• Calibration of hygrometers, saturated salt solution and humidity related measuring equipment from 5 %rh to 95 %rh.
  

• Calibration of dewpoint meters from -75 °C to +70 °C.
  

• Calibration of water activity meters from 0,05 aw to 0,95 aw.
  

• Traceability for radiation thermometry is obtained from contact thermometers up to 500 °C and from a spectrally characterised monochromatic radiation thermometer calibrated at the freezing point of silver (961.78 °C) or copper (1084.62 °C) from 600 °C.
  

• Temperature and Humidity metrology practical training to industry and African national metrology institutes.
  

• Provide training through internships and bursary programmes.
  

• Supports fair trade, by underpinning an internationally respected measurement infrastructure in South Africa.​
  

• Primar​​​y traceability for contact thermometry

• The national measurement traceability for ear radiation thermometers

• Radiation​ thermometry and black body source measurement in the sub-zero temperature range

• The national measurement traceability for Thermal imager
  

The T​​eam

• S​​ANAS Specialised Technical Committee (STC) meetings every year

• AFRIMETS Technical committee meeting every year

• APMP Technical committee meeting every year

• CCT Technical committee meeting every two years​
  

Co​​ntact

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