RS Korea — FIX800 Five-Gas and O₂ Detector Addition with Online IoT Monitoring, Pohang Water Reclamation Center

RS Korea returned to the Pohang Water Reclamation Center — a site first serviced over two years ago in October 2023, where a CO detector had been installed for fire detection in the sludge storage warehouse and a three-gas (O2/H2S/EX) detector for confined-space asphyxiation prevention at the sludge unloading dock — to add three new fixed detectors and build an integrated IoT monitoring system. Regarding "confined space" classification: although the unloading dock appears open, its shutter remains closed except during unloading operations. Under Appendix 18 of Article 618 of Korea's Occupational Safety and Health Standards, a space qualifies as confined not only by its physical enclosure but also by whether hazardous gas is present or likely to accumulate faster than ventilation can clear it — meaning even an apparently open space can be legally classified as confined. This project covered two objectives: (1) adding a FIX800 five-gas detector at two locations and a FIX800 single-gas (O2) detector at one additional location, and (2) integrating both new and existing detectors into a unified web-based monitoring system via IoT. Three new installation points, based on regulatory requirements: - Basement level 1 sludge treatment area - Basement level 2 sludge treatment area - Level 3 fire-suppression agent room The two basement sludge areas fall under Item 11 of the confined-space regulation, while the level 3 fire-suppression room falls under Article 628-2, Clause 6, which requires oxygen or carbon dioxide detection and alarm equipment in any CO2 fire-suppression protected zone where the distance to the nearest exit exceeds 10 meters, or where 100 or more 45 kg CO2 extinguishing cylinders are stored. Equipment installed: The two basement sludge dock areas received the legally required five-gas detector (accounting for CO2 and CH4 generated during extended sludge dwell time), while the level 3 CO2 agent room received a single O2 detector per regulation. A 10-channel FIX-DS display board was custom-built to simultaneously show readings from both new basement locations. The centerpiece of this project was FIX-AP, RS Korea's IoT hardware module enabling both new and existing detectors across all locations to be monitored remotely from an office PC via the web — made possible by growing demand for online monitoring and a newly developed 2-channel RS485 slave terminal supporting simultaneous field and office monitoring (see RS Korea's earlier post on FIX-AP-based multi-point monitoring for further detail). Installation work: Elevated work using a rented lift was required to run cabling cleanly across all four points. RS Korea's on-site manager periodically checked gas concentrations throughout the work — a gas-measurement specialist experiencing a gas incident on its own job site would be the ultimate irony. Multiple technicians worked in parallel on detector mounting, display board installation, and cable routing. The O2 detector for the CO2 fire-suppression room was wired to a 2-way RS485 board feeding both the FIX-DS display and FIX-AP module, using 6-core shielded cable for power and dual communication lines. After powering each detector, readings were cross-checked against a portable reference detector, while LAN cabling was run to connect FIX-AP to the server — a hardwired connection was chosen over WiFi/router setup due to the difficulty of installing routers across multiple separated site locations. Internet connectivity and server communication were both confirmed working correctly. The full installation, including cable runs, rewiring, and elevated communication line work across multiple sites, took three days to complete. The project concluded with a live demonstration of server access via web browser from the control room PC. The client specifically noted the convenience of no longer needing to log safety readings manually on a time-by-time basis at the site. RS Korea continues to develop WANDI products that combine the intuitive on-site displays workers prefer with the remote monitoring convenience site managers need.