Oxygen Depletion in Enclosed MV Switchgear: O₂ and SF₆ Monitoring at CHP Substations
SF₆ leaks in enclosed switchgear displace oxygen below safe levels with no smell or visible warning. How to combine SF₆ and O₂ monitoring with Rapidox at combined heat and power substations.
⚠️ EN version — draft. Ready to publish once kk/en routing (i18n) is implemented across the site.
SF₆ is heavier than air. When it leaks from a gas-insulated switchgear (GIS) cell or enclosed MV cubicle at a CHP substation, it displaces oxygen at floor level — an invisible asphyxiation risk before the cell pressure alarm trips.
A complete safety programme needs two loops: gas quality inside the breaker (Rapidox SF6 6100) and atmosphere monitoring in the room (Rapidox SF6 Fixed Detection System). Portable multi-gas units (6100 QUAD, Clean Air Pumpback) support walk-downs of mixed SF₆ and SF₆-free bays.
O₂ limits: ≥19.5% safe; 16–19.5% restricted entry; <16% no entry until forced ventilation. Sensors belong at floor level, integrated to plant SCADA where possible.
Pair gas checks with partial discharge ultrasound and auxiliary equipment vibration on the same CHP inspection round. Scope: power generation — CHP, thermal and hydro plants; not oil & gas facilities.
Request a consultation for Rapidox fixed and portable configurations.
Equipment in this article
Rapidox SF6 Fixed Detection System - Fixed Monitoring System
Fixed continuous monitoring system for detecting SF6 insulating gas leaks in ele...
Rapidox 6100 Clean Air Pumpback - Dry Air and SF6 Analyzer
Gas analyzer for dry air and SF6 insulating gas analysis with gas return functio...
Rapidox SF6 6100 - Portable SF6 Gas Analyzer
Portable gas analyzer for measuring moisture, purity and decomposition products ...
Rapidox 6100 QU4D Multi-Gas - Multi-Gas Analyzer
Multi-gas analyzer with gas return function for comprehensive analysis of electr...
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