Oxygen Deficiency Monitoring – A Primer on the Problem of Oxygen Depletion
The air you breathe is not infinitely available. There are instances and places where oxygen levels go down to dangerous levels as to create a health hazard for those in the immediate vicinity. This happens to both the home environment as well as the work environment.
At normal atmospheric pressure (found at sea level), normal oxygen concentration level is pegged at 20.9%. The Occupational Safety and Health Administration (OSHA) define oxygen deficiency to be oxygen concentration that goes below 19.5%. Hence, a drop of oxygen content by a measly 1 to 1.5 percentage points is considered by the authorities as a human safety hazard.
Instances when this can happen is not an impossibility as it is a known hazard in many workers environment in the chemical industries, refineries and many others. If personnel are required to work in areas where there is limited or no natural ventilation, then there is the possibility that they could get exposed to a situation where the oxygen concentration in the air is depleted.
This can happen inside storage tanks, vats, underground vaults, sewers, manholes, silos and boilers when oxygen is displaced by other types of gases that may be leaking out of gas lines, process valves, or leaks from storage tanks. An example would be leaking liquid nitrogen which is known to evaporate and turn to nitrogen gas very quickly. Nitrogen expands quite rapidly and displaces other gases such as the live-supporting oxygen.
Protection from such occurrences come in the form of oxygen deficiency monitoring devices which are electronic devices equipped with electro-chemical sensors that detects oxygen in the air and determines its concentration. It sounds off an alert whenever the concentration level goes below a certain threshold level so persons affected can take immediate action.
Installation of such devices in areas where such hazards are deemed to be probable is mandated by the government agencies like the Occupational Safety and Health Administration (OSHA) and companies have the option of installing permanent monitoring devices as fixtures in those areas. Another type of monitors is the portable oxygen monitoring devices that personnel can take with them all the time. They give continuous protection wherever the workers go and so it is a good complement to fixed monitoring systems. When it comes to worker safety, redundancy is highly advised.
For more information about oxygen monitoring as well as safety policies covering working environments, please visit the author’s online oxygen monitors guide.
