Toxic Gas Detection in Ammonia Plants for Shelter-In-Place

Multiple gas detection mechanisms are available in the process industry, with applications ranging from modeling gas releases, to detecting an accidental release in a process facility, which may trigger a shutdown or mitigation function. Many of those technologies are used for gas detection in ammonia plants, in order to protect personnel and equipment. Toxic Shelter-In-Place (SIP) or Toxic Safe Havens are vital for deployment of gas detection as part of a strategy to manage risks from Toxic releases, as they can help shelter or safely evacuate personnel based on the ammonia gas concentration during a release scenario. Toxic SIPs depend on reliable, timely toxic gas detection in order to allow the ventilation system configuration to be aligned to the specific sheltering mode and to alert personnel that toxic emergency procedures must be implemented. This paper discusses the application of various gas detection technologies to strengthen the SIP by providing much-needed data in the form of gas concentrations at various locations within the plant and also within the SIP to prevent personnel from evacuating when it is safer inside the SIP, or to ensure that occupants evacuate when necessary. This paper also compares different technologies in terms of response times, power requirements and measurement ranges.