Atmospheric Vent Gas Monitoring
Accurate vent gas monitoring helps operators control emissions, maintain safety and meet environmental compliance requirements.
Over 45 Years in Operation
1000's of UK Installations
Supporting 100's of UK Sites
Introduction
Atmospheric vent gas monitoring is used to detect and measure gases released from industrial systems, including tanks, process lines, analyser vents and safety relief systems.
These emissions can include methane, carbon dioxide, volatile organic compounds (VOCs), hydrogen sulphide and other hazardous gases. Monitoring ensures that releases are controlled, understood and kept within safe and compliant limits.
In many industrial environments, vent gas monitoring is not just about compliance, it provides valuable insight into system performance, leaks and process inefficiencies.
The Problem
Vent gas systems are often overlooked because they are not part of the main process, but they present significant safety, environmental and operational risks if not properly monitored.
Common challenges include:
- Low flow and intermittent gas release that is difficult to detect
- Corrosive or contaminated gases affecting traditional sensors
- Lack of visibility of emissions to atmosphere
- Difficulty detecting leaks before they become safety risks
- Compliance requirements for VOC and methane emissions
- Traditional detection methods requiring frequent maintenance or calibration
In many cases, operators rely on periodic checks or basic instrumentation, which can lead to undetected emissions and incomplete reporting.
The Solution
Laser-based gas detection systems provide a highly reliable solution for atmospheric vent gas monitoring, offering continuous, real-time measurement with minimal maintenance.
Using Tunable Diode Laser (TDL) technology, these systems deliver precise gas concentration measurement without drift, making them well suited to long-term monitoring applications such as Flare Gas Metering and Biogas Flare Gas Monitoring, where emissions data is critical.
They are also commonly used for Fugitive Emissions Monitoring or within systems used for Nitrogen Blanketing, where understanding gas movement and system behaviour supports safe operation.
Open path and point detection systems can be deployed depending on the application, allowing operators to monitor either specific vent points or larger areas for leaks and emissions.
Technical Insight
Atmospheric vent gas monitoring presents unique challenges that require careful selection of measurement technology.
Low flow and dilution effects
Vent gases are often released at very low flow rates and may be diluted in air, making detection more difficult. High-sensitivity detection methods are required.
Wide range of gases
Typical gases include methane (CH₄), carbon dioxide (CO₂), hydrogen sulphide (H₂S), oxygen (O₂), carbon monoxide (CO) and VOCs such as benzene, toluene and xylene (BTX).
Harsh and variable environments
Vent systems may be exposed to temperature changes, weather conditions and corrosive gases, requiring robust and stable instrumentation.
Continuous monitoring vs spot checks
Fixed systems provide continuous monitoring and data logging, while portable systems are often used for inspections and confined space checks. Fixed systems are preferred for compliance and reporting.
Area vs point detection
- Point detection measures gas concentration at a specific location
- Open path detection measures gas concentration across a distance, making it ideal for leak detection and perimeter monitoring
Data and compliance
Modern systems provide continuous data logging, remote access and integration into control systems, supporting environmental reporting and audit requirements.
Recommended Products
TDL Gas Detector
High-accuracy laser-based analyser for continuous monitoring of specific vent points and process emissions.
Open Path Laser Gas Detector
Designed for area-wide leak detection and perimeter monitoring, providing early warning of gas releases across larger spaces.
Find out more about gas detectors here
Key Benefits
- Early detection of gas leaks and emissions
- Improved safety for personnel and plant
- Supports environmental compliance and reporting
- Reliable long-term monitoring with minimal maintenance
- Suitable for low flow and diluted gas conditions
- Provides real-time visibility of venting behaviour
Need information or advice?
Speak with our friendly, expert team to discuss your requirements and find out how we can help you.
Atmospheric Vent Gas Monitoring FAQs
Explore common questions about vent gas monitoring, including how systems work, what gases are measured and how to select the right solution.
What is atmospheric vent gas monitoring?
Atmospheric vent gas monitoring involves detecting and measuring gases released to atmosphere from industrial systems such as tanks, process lines and vents. It helps operators understand emissions, maintain safety and comply with environmental regulations.
Why is vent gas monitoring important?
From experience across industrial sites, vent points are often where issues first appear - whether that’s a small leak, process upset or equipment fault. Monitoring provides early warning, improves safety and ensures emissions are properly reported and controlled.
What gases are typically monitored?
Common gases include methane (CH₄), carbon dioxide (CO₂), hydrogen sulphide (H₂S), oxygen (O₂), carbon monoxide (CO) and VOCs such as benzene, toluene and xylene. The specific gases depend on the process and application.
What is the best technology for vent gas monitoring?
Laser-based systems using TDL technology are widely used because they provide accurate, drift-free measurement with minimal maintenance. Open path systems are ideal for detecting leaks over large areas, while point detectors are used for specific vent locations.
Can low-level emissions be detected reliably?
Yes, but it depends on the technology used. Laser-based systems are particularly effective for detecting low concentrations and diluted gases, which are common in atmospheric venting applications.
Do vent gas systems need continuous monitoring?
In most industrial and regulated environments, continuous monitoring is preferred as it provides a complete record of emissions and allows operators to detect issues as they occur rather than relying on periodic checks.
How do I choose the right vent gas monitoring system?
Selection depends on gas type, detection range, site layout and whether point or area monitoring is required. In practice, many systems combine both approaches to provide full coverage and reliable detection.
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