Optical gas cameras
Optical Gas Imaging (OGI) cameras use spectral wavelength filtering and sterling cooler cold filtering technology to visualize the infrared absorption of VOC/ Hydrocarbon, SF6, refrigerants, carbon monoxide and other gases whose spectral absorption matches the response of the camera.
By using OGI technology, companies can incorporate a ‘Smart LDAR’ (leak detection and repair) program that allows operators to safely and efficiently visualize gas leaks. OGI has allowed companies to reduce industrial emissions and operators to conform to future regulations.
In addition, OGI saves money, as part of a much more efficient process, but most importantly it improves the safety of their assets and their personnel.
To get the most out of OGI equipment, you should consider the following tips.
1. Understand the application and needs
Different applications require different cameras. In other words: one camera may not see all the gases, so you need to understand which type of gas you are dealing with. For example, a VOC/ Hydrocarbon OGI camera will not see SF6 and a CO camera will not see refrigerants.
2. Environmental conditions
The success of passive optical gas imaging depends on environmental conditions. The greater the background energy differential, the easier the camera will be able to visualize the gas leak and pinpoint its source.
Active optical gas imaging (i.e. using a laser based backscattering technique) relies on a reflective surface in the background. This presents a significant challenge when you are looking at components high up and pointing the camera at the sky.
Also, rain and strong winds need to be taken into account. Rain can make detection very difficult, but wind can actually help visualize the gas because it makes the gas move.
3. Optical gas imaging is qualitative
Due to the environmental variants, background energy differential and variations, an OGI camera will not be able to tell what amount of gas is leaking or which gas it is. An OGI camera will however pinpoint the source of the leak in the most efficient and effective way.
4. Use a sniffer probe
Use an OGI camera to visualize the leak and trace its source. Then, use a sniffer probe – a toxic vapour analyser (TVA) or organic vapour analyser (OVA) to quantify the leak. Combining an OGI camera with a sniffer probe is referred to as Smart LDAR.
5. Use all the features and functions
Certain OGI cameras – including all of FLIR’s GF-series cameras - are dualuse systems. They can also be used for industrial maintenance inspections, including high- and low-voltage electrical installations, mechanical installations, pipework and insulation, ovens and many more.
The thermographic function on your OGI camera will also help you determine the background temperature/ energy the gas is absorbing. Unlike with other thermographic applications, your object of detection (gas) has no visual representation and it is moving constantly. Therefore, a continuous focus is most important and so is the thermographic capability to determine the temperature range settings. An OGI camera also allows you to record a movie to capture the movement and pinpoint the leak. It is always advised to take a visual image.
6. Keep it safe
A gas imaging camera is a quick, noncontact measuring instrument that can also be used in hard to access locations. It can detect small leaks from several metres away and big leaks from hundreds of meters away.
It can even show leaks on moving transport vehicles, greatly improving the safety of both the inspector and the plant. Thanks to their sensitivity and, with some cameras, the high sensitivity mode (HSM), you can scan for leaks from a safe zone or even from a greater distance, compared to traditional gas detection methods.
7. Consider future emissions regulations
FLIR Optical Gas Imaging cameras detect dozens of volatile organic compounds, including the greenhouse gas Sulphur Hexafluoride (SF6), hereby efficiently contributing to a better environment. Optical gas imaging cameras also allow you to comply with new industrial emissions regulations & procedures.