Can I identify a flare with a performance issue: Helicopter Optical Gas Imaging

Can I identify a flare with a performance issue? > Can I identify a flare with a performance issue: Helicopter Optical Gas Imaging

The use of helicopter mounted optical gas imaging (OGI) technology to identify unlit flares through the thermal signature of gas being emitted from the flare.  The use of helicopters means that large areas, and large numbers of flares, can be inspected in a short period of time without the need for extended travel time between sites of interest

How it works 

Gas emitted from an unlit flare reads to a localised drop in air temperature. This can be seen by Infrared thermography as a black plume, allowing unlit flares to be distinguished from non-operational flare stacks.


  • Can be conducted concurrently with leak detection and repair (LDAR) surveys
  • Can be used in conjunction with wide area methods (e.g. satellites) to identify and locate specific methane anomalies
  • Can cover large areas rapidly, allowing multiple flares to be inspected


  • Cannot measure methane directly or distinguish between gases
  • Requires a stable platform, such as a helicopter to provide sufficient observation time for the plume to be identified
  • Non quantitative

Case study

Permian Map Project

  • Five surveys of over 1000 flares in 2020 –2021
  • Preliminary results indicate ~7% of flares are unlit and venting and another ~5% have combustion issues.

The Permian Methane Analysis Project (PermianMAP) is an initiative that combines established data collection methods with state-of-the-art technologies to pinpoint, measure and report on oil and gas methane emissions in the Permian Basin. The results are made publicly available. it includes identification and analysis of methane from a variety of sources including flares. The use of helicopter mounted OGI cameras has identified methane plumes from different locations and sources, as shown in the images below.

Images courtesy of the Environmental Defense Fund.

OilandGasMethane (2) OilandGasMethane (1)

OGI - Optical Gas Imaging

OGI detects the distinct thermal signature of methane gas as it is emitted in to the atmosphere. It is widely used for activities such as leak detection and repair, but can also be used to identify a flare that is poorly combusting or extinguished.   The majority of observations are qualitative rather than a quantitative assessment of flow.

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