KEBS National/ Primary Mass Laboratory
Tasks
- Maintain and assure the traceability of the National Measurement Standards of Mass
- Dissemination of the unit of mass by calibration of weights and mass standards in the range of 1mg to 2000kg.
- Calibration of a highly accurate and reliable equipments related to these national unit
- Conduct technical consultancy, training, and advice in Mass and Weight related fields
- Participate in national and international comparison measurement
Traceability:Since the 1st General Conference of Weights and Measures in 1889, the unit of mass has been defined as follows: The kilogram is the unit of mass; it is equal to the mass of the international prototype of the kilogram.
The international prototype of the kilogram is a cylinder 39 mm in height and 39 mm in diameter. It consists of an alloy of 90% platinum and 10% iridium (Pt-Ir) and has a density of approximately 21500 kg/m3.
It is maintained at the International Bureau of Weights and Measures (BIPM) in Sèvres near Paris.
Highest National standards related to KEBS mass laboratory are two sets of class E1 mass standards that range from 1mg to 10kg. These standards are stainless steel and are traceable to the National Prototype kilogram of the Federal Republic of Germany No. 52 which is linked up with the international prototype kilogram.
Calibration Services
Calibration of mass standards:
Mass pieces are calibrated using a variety of mass comparators. The laboratory is equipped with the both automated and manual electronic mass comparators with the capability of attaining the uncertainty requirements of OIML class E.
Computational software developed at KEBS enables accurate, traceable calibration of weights. The computations take into account important environmental influences, particularly air density. The most significant determinations are the estimates of variances and their propagation through the mass chain.
The laboratory has the capacity to check and ascertain the magnetic properties of mass standards through use of the susceptibility meter. The accuracy of mass measurement can be greatly affected by the magnetic susceptibility of weights. For high accuracy and conformance to a class (E1 to E2 and some ASTM classes), it is important to verify that magnetic susceptibility is sufficiently small.
Currently the laboratory is accredited by DKD of Germany to OIML class F1 based on ISO/IEC 17025 and is in the process of upgrading this accreditation to class E2 by the close of the year 2009.
Visit
www.dkd.eu laboratory number DKD-K-20001 for details.
Capabilities:The laboratory has capability of calibration of mass standards in the range of 1mg to 20kg OIML class E2, F1, F2, M1, M2 & M3 as detailed below:
Measurement |
Range |
Best Measurement
Uncertainty |
OIML Class E2 |
1mg – 10kg |
1/5th of OIML tolerance |
OIML Class F1 & F2 |
1mg – 10kg |
1/3rd of OIML tolerance (DKD accredited) |
OIML Class M1 |
1mg – 10kg |
1/3rd of OIML tolerance (DKD accredited) |
OIML Class M2 |
100mg – 20kg |
1/3rd of OIML tolerance |
