BS ISO 4266-2:2002

1 Scope
2 Normative references
3 Terms and definitions
4 Precautions
  4.1 Safety precautions
      4.1.1 General
      4.1.2 Equipment precautions
  4.2 General precautions
      4.2.1 Accuracy and performance
      4.2.2 Speed of response
      4.2.3 Protection from mechanical damage
      4.2.4 Manual gauging
      4.2.5 Minimum measurable level
      4.2.6 Trim and list
      4.2.7 Product temperatures
      4.2.8 Compatibility
      4.2.9 Entrained air and vapour
      4.2.10 Vessel motion
  4.3 Use of marine ALGs in fiscal/custody transfer
5 Accuracy
  5.1 Intrinsic error of ALGs
  5.2 Calibration prior to installation
  5.3 Initial shipyard adjustment
  5.4 Error caused by operating conditions
  5.5 Overall accuracy
      5.5.1 General
      5.5.2 Use of ALGs for fiscal/custody transfer purposes
6 Installation of marine ALGs
  6.1 General
  6.2 Location of ALG
  6.3 Location of manual calibration check point
  6.4 Gauging of inerted tanks
7 Onboard verification of marine ALGs
  7.1 General precautions
      7.1.1 Check for smooth operation of level-sensing
             elements - at the shipyard
      7.1.2 ALG technology-specific considerations
  7.2 Verification by innage gauging or ullage gauging
  7.3 Initial verification
  7.4 Subsequent verification
      7.4.1 General
      7.4.2 Agreement between ALG reading and manual
             gauge reading
      7.4.3 Use of average gauge readings
      7.4.4 Adjustment of the ALG
  7.5 Verification by alternate methods
  7.6 Schedule for regular ALG verification
  7.7 Record keeping
8 Data communication and receiving
  8.1 Introduction
  8.2 Use of remote readout in fiscal/custody transfer
  8.3 Telemetry and readout equipment
Annexes
A - Accuracy limitations of marine level measurement
B - Accuracy limitations of marine volume measurement
Bibliography

Provides guidance on the accuracy, installation, calibration and verification of automatic level gauges (ALGs), both intrusive and non-intrusive, for measuring the level of petroleum and liquid petroleum products having a Reid vapour pressure less than 100 KPa, transported aboard marine vessels (i.e. tankers and barges).

This part of ISO4266 gives guidance on the accuracy, installation, calibration and verification of automatic level gauges (ALGs), both intrusive and non-intrusive, for measuring the level of petroleum and liquid petroleum products having a Reid vapour pressure less than 100kPa, transported aboard marine vessels (i.e. tankers and barges).

This part of ISO4266 gives guidance for buyers and sellers who mutually agree to use marine ALGs for either fiscal and/or custody transfer applications.

This part of ISO4266 is not applicable to the measurement of level in refrigerated cargo tanks.