This article provided the rigorously compiled hydrocarbon release database (HCRD) data set developed by the U.K. Health and Safety Executive (HSE) in cooperation with the U.K. North Sea oil and gas industry.

This data set includes leaks of all sizes recorded in a standardized way and normalized by an equipment count to allow data to be reported as leaks per year for process equipment or leaks per meter-year for pipework.

Equipment Type Frequency of Full Leaks ≥1 mm Diameter Frequency of Full Leaks ≥50mm Diameter
Steel pipes (2") 1-m length 5.70E-05 0.00E+00
Steel pipes (6") 1-m length 2.00E-05 7.70E-08
Steel pipes (18") 1-m length 1.10E-05 4.20E-08
Flanged joints (2") 3.20E-05 0.00E+00
Flanged joints (6") 4.30E-05 3.60E-07
Flanged joints (18") 1.20E-04 1.10E-06
Manual valves (2") 1.40E-05 0.00E+00
Manual valves (6") 4.80E-05 4.90E-07
Manual valves (18") 2.20E-04 2.30E-06
Actuated valves (6") (non-pipeline) 2.60E-04 1.90E-06
Instrument (0.5") 2.30E-04 0.00E+00
Process vessel 5.00E-04 1.10E-04
Centrifugal Pump 1.80E-03 2.40E-05
Reciprocating Pump 3.70E-03 5.20E-04
Centrifugal Compressor 2.00E-03 2.00E-06
Reciprocating Compressor 2.70E-02 1.10E-05
Heat Exchanger (Hydrocarbon in shell) 1.40E-03 1.30E-04
Heat Exchanger (Hydrocarbon in tube) 1.00E-03 4.90E-05
Heat exchanger (plate) 6.00E-03 3.60E-04
Heat exchanger (air cooled) 1.20E-03 6.90E-05
Filter 8.90E-04 6.40E-06