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Oxygen (O2)

Last updated: November 30, 2021

What Does Oxygen (O2) Mean?

Oxygen (O2) is a gas, an essential component of air, and a necessary element for the sustenance of all living things. It is colorless, odorless, and tasteless and makes up 21% of the Earth’s atmosphere.

In workplace settings, the air must contain an oxygen concentration between 19.5% and 23.5% to be considered safe, according to OSHA.

Oxygen is also an important industrial gas used for various processes, such as the production of acids, steel, iron, polyester, polymers, and antifreeze, as well as cutting, welding, and melting metals. Additionally, oxygen can have a combustile reaction with certain materials, creating a fire and explosion hazard.

Safeopedia Explains Oxygen (O2)

Oxygen is the 8th element in the periodic table, with an atomic weight of 15.9994 and a density of 0.001429 grams per cubic centimeter. The melting point of oxygen is -361.82° Fahrenheit and the boiling point is -297.31° Fahrenheit. It is the third most abundant element in the universe and accounts for nearly half the mass of the Earth’s crust.

The Importance of Oxygen

Without oxygen supply to the lungs, humans can die within minutes. However, too much oxygen can also impede the normal functioning of the body. Workplaces must, therefore, have adequate ventilation and other measures in place to ensure that employees have sufficient oxygen without being exposed to excessive concentrations of it.

Humans inhale air that contains about 21% oxygen. A few percentage points below that can make functioning laborious. At 10 to 12% oxygen levels, breathing becomes difficult and judgment can be impaired. 8 to 10% can result in fainting and unconsciousness. Oxygen levels of 6 to 8% can cause death wtihin eight minutes.

Oxygen Levels in Confined Spaces

Many jobs in oil and gas, mining, construction, and utilities require workers to enter confined spaces. These spaces often contain oxygen deficient atmospheres and must be continuously monitored and anyone working inside them may need to be equipped with oxygen supplying respirator, such as an SCBA.

Confined spaces like manholes, storage tanks, silos, and tunnels can be easy to recognize. However, some confined spaces are not quite so obvious, including degreaser tanks, open pits, and enclosures with bottom access. While these may be open to some extent, they prevent natural ventilation from taking place, which can result in a lower concentration of oxygen.

Preventing Oxygen Depletion Incidents

Several measures can be taken to help prevent incidents caused by low oxygen:

  • Use personal protective equipment (PPE) and appropriate breathing apparatus where necessary
  • Before entering a confined space, ensure that a supervisor has been notified and is aware that the entry is taking place
  • Be aware of the symptoms associated with oxygen depletion
  • Be up to date with emergency procedures in case of an incident
  • Carry a personal mointoring device, especially when working alone in a confined space

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Process SafetyEmergency ServicesEHS ProgramsIndustrial HygieneConfined SpaceRespiratory ProtectionRemediation

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