Blog 2: The Hidden Dangers of Oxygen Deficiency in Confined Spaces
One of the most dangerous confined space hazards is oxygen deficiency. Normal air contains about 20.9% oxygen. When this drops below 19.5%, it’s considered unsafe for workers — and at 12% or less, unconsciousness and death can occur within minutes.
Causes of Oxygen Deficiency in Confined Spaces
- Gas displacement – Nitrogen, carbon dioxide, or other gases push oxygen out.
- Oxygen consumption – Rusting metal, burning fuel, or decaying organic matter use up oxygen.
- Chemical reactions – Certain processes reduce oxygen levels unexpectedly.
Why It’s Hard to Detect
You can’t smell, taste, or see oxygen deficiency. Early symptoms — dizziness, confusion, rapid breathing — often come too late to act.
How to Prevent Oxygen-Related Accidents?
- Always conduct confined space gas testing before entry.
- Monitor air continuously while work is ongoing.
- Use PPE for confined space work, such as supplied-air respirators or SCBA, when oxygen is low.
- Ventilate the space thoroughly before and during entry.
Safety Reminder: Guessing air quality can cost lives. Only proper testing ensures a confined space is safe to enter.
