In view of globalization and international competitiveness in trade and commerce and the introduction of ISO 9000, the quality of products and services has emerged as the forerunner of all activities in industries. Measurement and calibration play an important role in fulfilling the requirements of industries to produce quality products. Measurement is the technical basis for development of the economy and trade. Uniform and internationally compatible measurements are beneficial in eliminating technical barriers to trade and promoting international cooperation.The validity of precise and accurate pressure measurements is essential in trade, efficiency, quality and safety. The role of pressure measurements is now well established in many industries. These applications are found in industries as diverse as nuclear, power, gas, fertilizer, pesticide, chemical, petrochemical, biological, hot and cold forging of steel, pharmaceutical and drugs, synthesis of super hard materials like diamond, optimization of domestic appliances like pressure cookers and filling cooking gas cylinders, assessment of health like blood pressure monitors, optical, aerospatial, defense, meteorological, automotive, semiconductor, environmental, ventilation, filtration and process control in general.The introduction of quality systems stipulates that all the critical instruments and apparatus being employed for calibration and testing activities should be periodically checked, calibrated and inter-compared against each other to establish and build up mutual confidence and to estimate the uncertainty associated with the measurements. In order to achieve the goals defined above, the new industrial pressure calibration laboratory should be established, keeping in view the following technical requirements.

Most of the industrial pressure calibration requirements are up to 200MPa in the hydraulic pressure region and up to 10MPA in the pneumatic pressure region. In the first phase, a calibration laboratory may be established at up to 140MPa, the most critical range, in the hydraulic, and 10MPa in the pneumatic range . The hydraulic range may be further extended up to 200MPa in the second phase. The national metrology laboratory should be equipped with primary pressure standards. However, the laboratory can be established using high precision dead weight secondary pressure balances in the first phase and the controlled clearance type pressure balances in the second phase. The following instruments are proposed to be procured as laboratory standards.

The proposal covers the measurement of pressure and calibration of pressure measuring devices.

Procurement of these instruments would enable the pressure calibration laboratory to provide the industries of the country with national traceability and apex level pressure calibration in the specified pressure range and also to take part in the future international/ national and bilateral inter-comparisons.

It should also be noted that there are some modern pressure controllers/calibrators available for both hydraulic and pneumatic systems. These controllers allow the operator to "dial up" the pressure required through an electronic controller and display unit. This makes day-to-day calibrations much simpler at accuracies very similar or better than the traditional working standards.

The approximate space or area required for the pressure calibration laboratory is estimated to be about 90 sq meters, including laboratory space, storage and handling of instruments received for calibration, and office space.

The room temperature and humidity in the calibration laboratory should be controlled within 23 ± 2° C and relative humidity within 50 ± 10 %, using air conditioners and de/humidifiers. The barometric pressure in the laboratory should be recorded. The value of local acceleration due to gravity (g) local should be measured/ known to the best possible measurement uncertainty.

The laboratory requires adequate managerial and technical personnel and resources to maintain and upgrade national standards and provide calibration services to industry. All the personnel involved in the calibration and testing work should be professionally qualified and trained and experienced in the use and application of the instruments and standards and the latest technology and measurement techniques in pressure metrology. They should also be trained in evaluating the errors and measurement uncertainty. The suggested qualifications are given below: