Lesson Review: Confined Space Entry
Confined spaces can be generally categorized as a space with open tops, a depth
that will restrict the natural movement of air and enclosed areas with very limited
openings for entry.
Hazardous situations within confined spaces can be classified into three areas:
• The material stored or used in the confined space; for example, damp activated
carbon in a filtration tank will absorb oxygen, and then create an oxygen
deficient atmosphere
• The activity carried out; for example, the fermentation of molasses that creates
ethyl alcohol vapors and decreases the oxygen content of the atmosphere
• The external environment; as in the case of sewer systems that may be affected
by high tides, heavier than air gases or flash floods.
Note the following key points in this lesson:
• Types of hazards can be classified into two categories: inherent and induced.
• Irritant or corrosive atmospheres can be divided into two groups: primary
and secondary.
• All employees required to enter into a confined or enclosed spaces should
be instructed as to the nature of the hazards involved, the necessary
precautions to be taken and in the use of protective and emergency
equipment required.
• Asphyxiating atmospheres involve the reduction of oxygen in a confined
space and may be the result of either consumption or displacement.
• When sufficient ventilation cannot be obtained without blocking the means
of access, employees in the confined space should be protected by air line
respirators in accordance with the requirements of Subpart E of OSHA
regulations.
It is essential that the
employer comply with
any specific regulations
that apply to work in
dangerous or potentially
dangerous areas.