Test Weight Traceability
Did you know that all Weighing Scales Ltd’s test weights are calibrated and ultimately traceable to one physical object?
This object is a Kilogram K unit of mass, it is a cylinder of platinum – iridium alloy which is stored at the International Bureau of Weights and Measures in France. Ostensibly this Kilogram has the same mass (weight) as one litre of water at freezing point. In 1889, 40 copies of the Kilogram K were distributed to the National Standards laboratories throughout the world.
The United Kingdom received Kilogram number 18. This is stored at the National Physical Laboratory and is known as the UK primary standard. The National Physical Laboratory in Middlesex ensures that the measurement of mass, force, pressure and density can be made traceable to internationally agreed standards.
The National Physical Laboratory calibrates weights by comparison to the primary standard for Trading Standards Departments. These weights are known as Local Standards and are held be Trading Standards Departments. Weighing Scales Ltd.’s reference weights are tested by Lancashire County Councils’ Trading Standards Department in Preston.
Traceability of test weights is maintained through a series of comparisons to a superior standard. Weighing Scales Ltd.’s UKAS calibrated reference weights are calibrated by comparison to local standards by Trading Standards. Weighing Scales Ltd internally calibrate all working weights against UKAS calibrated reference weights. Weighing Scales Ltd.’s reference test weights are accurate to Class F1 and Weighing Scales Ltd.’s working test weights are accurate to Class M1.
Overall, Weighing Scales Ltd test customer scales and weights using test weights which are traceable to national and international standards and ultimately the platinum – iridium alloy cylinder located in France!
Weighing Scales Ltd not only deal with weights but also scales, & microscopes or temperature & humidity testing. Check out our sister company – Temperature Test – for more information on all things temperature & humidity related.
Call us on 01282 691602 to discuss your calibration needs.