Pressure Calibration

This standard specifies the tolerances and limits for simple forms of pressure gauges such as:

• Bourdon tube pressure gauges
• Indicating pressure gauges
• Vacuum gauges
• Combined vacuum and pressure gauges (compound gauges)

Care and use

1. Always select the pressure gauge that best fits the application
2. Care should be taken while using pressure gauges.  Should you drop a pressure gauge, it should be re-calibrated/repaired before reusing it
3. Always clean pressure gauges after use with a cloth
4. Do not use excessive force when connecting the pressure gauge to the test rig otherwise damage may occur to the connector
5. Never use a pressure gauge that has not been calibrated, if in doubt consult an appropriate authority

It is highly recommended that an appropriate authority such as a UKAS approved laboratory carries out a full calibration on pressure gauges at least once a year.  In between UKAS calibrations at a frequency based on usage, pressure gauges coulld be calibrated in-house. A typical in-house calibration would include a written procedure and an associated calibration record sheet, which would contain as a minimum, the following listed information:

Pressure Gauge

(a) Serial number

(b) Location

(c) Procedure number

(d) Accuracy class

(e) Results

(g) Measurement uncertainty

(h) Sentence if appropriate

(i) Date and calibrators signature

(j) Traceability to National Standards

It is necessary that any person carrying out such calibration work should have received appropriate training and have shown the ability to be confident via a suitable training authority. Training records should be held and maintained.

Following are layouts for typical in-house calibrations for pressure gauges:

Calibration to be carried out in accordance with in-house procedure number …………………..

Serial Number:

Make:

Calibration Date:

Sizes:

FEATURE EXAMINED                      SPEC.                      MEASURED RESULTS

Applied Pressure

The pressure gauges were visually inspected for damage and the following faults were noted:

MEASUREMENT UNCERTAINTY +/- 0.017% of reading, Range 550 kPa to 110 MPa – (Applicable for UKAS calibrations only)

Source: UKAS schedule of accreditation, Calibration and measurement capability (CMC)

Calibrators Signature: ………………………………….

A traceability statement in this section would be required for all items and their relevant certification utilised for the calibration of plain limit gap gauges.