Sierra-Olympia Technologies has confirmed that its cameras comply with OOOOa, OOOOb, OOOOc, and Appendix K regulation standards.
These standards set the minimum requirements for detection and visualization capabilities for optical gas imaging (OGI) cameras. Below is an outline of the testing process used to demonstrate that the company’s OGI cameras meet these regulations.
OOOa was the initial regulation, setting the threshold at 60 grams per hour for a mixture of 50% methane and 50% propane, equivalent to about 10,000 parts per million (PPM).
However, the updated EPA regulations now focus on three specific control gases: methane, propane, and butane. For the new oil and gas regulations, the visualization requirements are 19 grams per hour for methane, 22 grams per hour for propane, and 29 grams per hour for butane.
Ventus OGI
The Ventus OGI can detect all three gases, and 19 Other Hydrocarbon Gases. While the Ventus OGI can visualize these gases, it does not distinguish between them; all gases will appear the same in the camera view.
Typically, customers k
now which gases are flowing through their systems and pipelines. If a leak occurs, they can identify the leaking gas with a high degree of certainty.
For a complete list of gases, visit the Ventus OGI product page >>
Appendix K Now Mandates an Operating Envelope
Appendix K now requires that an operating index and envelope be established by either the end user, operators, manufacturers like Sierra-Olympia Technologies, or service companies.
When using an OGI camera, particularly as an alternative to Method 21 sniffers, it is essential to validate the collected data and test results. During the latest testing for Appendix K validation, Sierra-Olympia followed the EPA’s approach to provide a model for others. Sierra-Olympia is reportedly the first company in the United States to implement this process.
Key parameters for OGI performance, audits, necessary equipment, facility inspections, record keeping, and field conditions were defined.
Operating envelope
OGI performance summary
Document proof that the OGI camera performs as specified in the Operating Enveloper definition.
Field condition validation
Establish the required environmental data for validation.
Performance audits
Provide evidence that the Operating Envelope was not exceeded.
Record keeping
Maintain records proving the inspection adhered to the Operating Envelope.
Necessary supplies
List essential items needed for inspections.
Site/facility inspection requirements, monitoring plan, training plan
Outline the core components of the monitoring plan.
These test parameters and the operating envelope were set to verify that the camera can meet leak detection and repair (LDAR) inspection requirements. Many companies do not test to this level of detail, focusing only on finding and fixing leaks rather than quantifying their size. If an auditor identifies a leak before the operator, fines can be issued retroactively to the last inspection, potentially accumulating substantial penalties.
In the Appendix K validation testing, the following conditions were used: wind speeds ranging from 0 to 10 m/s (0-22 mph), distances from 2 to 25 meters (6 to 82 feet), and Delta T values from 1 to 15°C. Two different lenses—25mm and 50mm—were employed, and three camera operating modes were tested: AGC (Standard), CLAHE (Contrast Limited Adaptive Histogram Equalization), and GEM (Gas Enhancement Mode).
Additionally, three digital zoom levels were used: 2X, 4X, and 8X. These tests determined the conditions under which the Ventus OGI could detect a 22 g/hr methane leak.
Testing parameters
Wind speed
0 – 10 m/s
Digital zoom
2X, 4X, 8X
Distance
0 – 25 m
Camera modes
AGC (Standard), CLAHE, GEM
Delta-T
1°C – 15°C
Lenses
25mm and 50mm
These factors can all affect detection capabilities. Monitoring from greater distances impacts the detection of leaks. In some tests, gas leaks were detected at distances of up to 1,000 feet, but these were measured in kilograms per hour, not grams per hour.
One of the quickest and easiest ways to validate the Ventus OGI camera has been to use Porta Gas bottles with a 50/50 methane-propane mix or propane cylinders typically used for grills or camping. Calibrated regulators set to 60 grams per hour or 6 grams per hour are employed for testing.
Operators can position the bottle at 6 to 10 feet from the camera and gradually increase the distance until the gas leak is no longer visible. This process helps establish the camera’s operating envelope under current weather conditions, including wind, sun, overcast skies, or light rain.
Both the EPA and air quality boards require facilities or manufacturers to define these criteria to ensure that operators are aware of their equipment’s limitations when conducting LDAR inspections, whether using aerial, handheld, fixed, or continuous monitoring OGI systems.
The findings revealed that as temperature differentials increase, observability improves. However, as wind speed increases, gas disperses, reducing observability. Similarly, observability decreases with distance. By using telephoto or longer, narrower field-of-view optics, some of these challenges were mitigated. For example, with a 25mm lens, these rules generally apply, but switching camera modes can enhance performance.
General observations
- Higher temperature differential reduces observability.
- Increased wind speed reduces observability.
- Greater distances reduce observability.
Examples of images taken in AGC, CLAHE, and GEM modes show how CLAHE enhances contrast and edge clarity compared to Standard mode. GEM mode, which colorizes gas, further improves visibility, allowing detection of the same leak from twice the distance in some cases.
Standard Mode
CLAHE Mode
GEM Mode
