Application Note All Rights Reserved, Copyright © December 2015, NEO Monitors AS A gas leak of HF (Hydrogen Fluoride) gas is dangerous to both humans and the environment. It is critical to detect an HF gas leak as early as possible to protect human health, warn of equipment or plant failure and to execute a process shutdown. The NEO Monitors OP (open path) HF detector is an excellent tool for early warning, because of its low detection limit of HF gas and short response time. NEO Monitors detectors can provide a detection barrier at the borderline of any area that contains HF gas. Therefore, it is well suited for fence line monitoring of an industrial plant, process or storage area. PROCESS: Fence line monitoring by OP HF detectors is well suited as a safety measure and detection barrier around a production facility at alkylation plants. Detectors are normally installed around and above the areas with potential HF leakage. It is recommended to place detectors above and in close proximity to equipment that poses a real risk of a gas leak: e.g. pump sets, pressure reducers, valves and pipe flanges. Detector placement is critical, as HF gas is lighter than air and will rise up into the air or into the facility’s roof/ upper levels. TYPICAL FENCE-LINE MONITORING INSTALLATION: 4 or more LaserGasTM III HF OP detectors. Detect ppm level of HF Path Lengths up to 100 meter Note: Shorter Optical path lengths helps identifying actual leakage points. Fig 1: Typical fence line monitoring with additional detectors, above and in close proximity to equipment that poses a risk of HF gas leak. NEO Monitors as • A subsidiary of Norsk Elektro Optikk • Prost Stabels vei 22 • N-2019 Skedsmokorset, Norway Phone +47 67 97 47 00 • www.neomoni

BENEFITS: • High sensitivity (detects low concentrations) for early detection of any leakage MOTIVATION: HF gas leak detection is critical to: • Achieve early warning of HF gas leaks • Protect human health and environment • All detectors operate independently and have their own laser and signal processor • Protect equipment and plant failure • No single point of fault failure • Low maintenance cost SOLUTION: The LaserGasTM III HF OP detector can detect very low concentrations of HF gas. The detector’s short response time ensures fast detection of an HF gas leak, and thus provides an early warning...