What is an LDSN?

A Leak Detection Sensor Network (LDSN) is an alternative means of providing Leak Detection and Repair (LDAR) compliance. When placed in a process unit or facility, a Leak Detection Sensor Network utilizes real-time sensors to monitor for in-facility leaks 24 hours per day, seven days per week.

If a leak is detected by the LDSN, an alert is sent, which prompts an LDAR technician to identify the leaking component for repair. The LDSN has the potential to provide the following advantages over traditional LDAR:

• • Reduced emissions through faster identification of leaks
• • Enhanced process safety with 24/7 monitoring of low- and high-level leaks
• • Reduced manpower on site
• • Potential cost reductions

The Detection Response Framework

An important extension of the Leak Detection Sensor Network (LDSN) is the Detection Response Framework (DRF). The Detection Response Framework represents the procedures used to respond to information delivered by the LDSN and to provide important information to the LDSN to ensure ongoing performance.

The LDSN system automatically detects and approximates the location of the emission source in the monitored process unit based on the VOC concentration, wind speed and wind direction. The LDSN then notifies the LDAR team of the detected emissions, who will then take appropriate action under the DRF.

A high-level detected emission that may represent a potential safety concern is communicated immediately through an alert and/or alarm. These alerts require immediate attention and can serve as an augmentation of existing facility safety systems. Other, more routine emissions are detected and communicated over time (hours to days), with repeating detected concentration peaks under varying wind directions building confidence in the assignment of an emission event.

Once a notification threshold is reached, a Potential Source Location (PSL) window is assigned. The LDAR personnel respond, per the DRF, to investigate the PSL and identify the source of the emission. The identified source is then measured with calibrated Method 21 equipment (or Optical Gas Imaging) to document the leak’s peak concentration value and initiate repair procedures. All information regarding the leak is efficiently entered into a mobile device and recorded for regulatory, operational, and quality assurance purposes. Other information, such as maintenance activities, are entered into the system to facilitate the operation of the LDSN.