Most confined-space incidents are atmospheric: too little oxygen, a flammable build-up, or a toxic gas. A four-gas monitor is the baseline tool — but the details decide whether it protects your team.
The standard four
- Oxygen (O2) — both deficiency and enrichment are dangerous
- Flammable gas (LEL) — alarms well below the explosive limit
- Carbon monoxide (CO)
- Hydrogen sulphide (H2S)
What to check before you buy
- Pump vs diffusion: a pump lets you pre-test the space from outside before entry
- Bump test and calibration: how easy is daily bump testing? Is a docking station available?
- Additional sensors: some jobs need CO2, VOCs (PID), SO2 or NH3
- Alarm clarity: loud, bright and with vibration for noisy plants
- Data logging: an exposure record for incident review and hygiene
Procedure still matters
The best detector cannot replace a permit system, ventilation, and trained attendants. Pre-entry testing should check from top to bottom of the space, because gases stratify.
EnviraH supplies Senko and other gas-detection instruments with bump-test gas, docking stations and calibration support. Browse detectors.
