Salient Features Of SRI Calibration Laboratory
- Wide Range Of Facilities In Different Disciplines Viz.
» Pressure/ Vacuum
» Rheology (viscosity)
» Electrical Devices
» Analytical Instruments
» On-line/ On-site
» National And International Traceability
Calibration! What is it ?
A set of operations, performed in accordance with a definite procedure,
that compares the measurements performed by an instrument to those made by a
more accurate instrument or a standard for the purpose of detecting and
reporting, or by adjustment, errors met in the instrument tested.
Purpose of Calibration
To ensure readings from an instrument are consistent with other instruments
and to determine the accuracy of the instrument i.e. that it can be trusted
for its observed/displayed measured value.
The value of calibration for industry
- To ensure that products are manufactured to specifications.
- To demonstrate that the industry operates a quality system and
technically competent and are able to generate technically valid
- To increase quality & value of product.
- The calibrated measuring instruments (working standards) have
the assurance of an unbroken chain of national/international
What is Traceability ?
Property of the result of a measurement or related to stated references,
usually national or international standards, through an unbroken chain of
comparisons all having stated uncertainties.
Why measurements must be Traceable ?
- Traceable measurements ensure the uniformity of manufactured
goods and industrial processes.
- To support equity in trade as well as compliance to regulatory
laws & standards.
- Essential to the development of technology.
- To provide traceable calibration of test and measurement
equipment is an ISO-9000 requirement(Purpose: With an eye to provide
safety and fitness for use) to ensure that the products manufactured
in one country will be acceptable in another on the basis of agreed
to measurement standards, methods & practices)
- Provides users with assurance of the confidentiality, validity
and accuracy of the data provided while testing.
Uncertainty- How accurate are your
It is a measure of the quality of a measurement & provides the means to
assess & minimize the risks and possible consequences of poor decision.
(A measurement with a stated uncertainty can be compared to others)
(Measurements are traceable when they can be related to recognised
measurement system through an unbroken chain of comparisons each with stated
Calibration Interval-Validity Period.
Validation is usually nominal maximum period between two successive
calibrations. The validity period is generally considered to be maximum
- The equipment is of good quality and is of proven adequate
- If any suspicion or indication of overloading or mishandling
arises, the equipment will be checked immediately and thereafter at
frequent intervals until it can be shown that stability has not been
- The extension of validity period is based on factors such as
history of stability, frequency of use, accuracy required, ability
of staff to perform regular checks and successful participation in
proficiency testing programs. It is the responsibility of the
testing authority to provide evidence that its calibration system
ensures that confidence in the equipment can be maintained.
Adequate records of the test data must be maintained
over a period of time to draw support for extension of validity period.
Calibration Measurement! How ?
- Verifying the performance of the test instrument which involves
applying a standard value to the instrument and observing how it
- Adjust the response of the instrument, wherever possible(After
verifying response, reset, adjust/correct the instrument via
internal control which in normal course is not accessible)
- Obtain correction factor for the test instrument.(Accordingly
correction factors/calibration constants are calculated &
incorporated in measurements)
SRI Calibration Laboratory provides valid and accurate
measurements using updated standards having unbroken chain of traceability
to National and International Standards.
SRI- CALIBRATION SERVICES (NABL Accredited)
- Glass Thermometer
- Dry & Wet Thermometer
- Digital Temperature Indicators/Controllers
- Temperature Recorders
- PRT/ RTD (Resistance Temperature Detectors)
- Thermocouples/ Pyrometers
- Oven, Furnace, Bath, Heating Chamber, Autoclave
- Deep Freezer, Incubators, Refrigerators
- - Analytical Balances