A confined space is defined as a
space that are not necessarily designed for people, but they are large enough
for workers to enter and perform certain jobs. Confined and enclosed space
operations have a greater likelihood of causing fatalities, severe injuries,
and illnesses than any other type of shipyard work. Some examples include:
tanks, vessels, silos, storage bins, hoppers, vaults, pits, manholes, or pipelines.
OSHA labels these areas as “permit-required confined space,” it is labelled
these when they contain a material that has potential to contain a hazardous
atmosphere, has walls that converge inward or floors that slope downward and
taper into a smaller area which could trap or asphyxiate an entrant.
Some more general terms to know
about confined spaces are as follows. "Acceptable entry conditions"
means the conditions that must exist in a permit space to allow entry and to
ensure that employees involved with a permit-required confined space entry can
safely enter into and work within the space. "Attendant" means an
individual stationed outside one or more permit spaces who monitors the authorized
entrants and who performs all attendant's duties assigned in the employer's
permit space program. "Authorized entrant" means an employee who is
authorized by the employer to enter a permit space. "Blanking or
blinding" means the absolute closure of a pipe, line, or duct by the
fastening of a solid plate (such as a spectacle blind or a skillet blind) that
completely covers the bore and that is capable of withstanding the maximum
pressure of the pipe, line, or duct with no leakage beyond the plate. "Entry permit (permit)" means the
written or printed document that is provided by the employer to allow and
control entry into a permit space and that contains the information specified
in paragraph (f) of this section. "Entry
supervisor" means the person (such as the employer, foreman, or crew
chief) responsible for determining if acceptable entry conditions are present
at a permit space where entry is planned, for authorizing entry and overseeing
entry operations, and for terminating entry as required by this section.
To
enter a permit-required confined space you first must be properly trained and
have the proper permit. You must know the proper procedures before entering and
know how and when to exit. Before you can enter the space you must identify any
physical hazards, test and monitor for oxygen content, flammability, toxicity
or explosive hazards as necessary. If there are such hazards, the employer then
would classify the space according to the physical and atmospheric hazards
found in it. The four classifications are: Isolated-Hazard Confined Space,
Controlled-Atmosphere Confined Space, Permit-Required Confined Space, and
Continuous System-Permit-Required Confined Space. The proposed requirements for
each type of confined space are tailored to control the different types of
hazards. The worker must be wearing the proper fall protection, rescue,
air-monitoring, ventilation, and lighting and communication equipment according
to entry procedures. While the worker is in the confined space they must be in
constant contact at all times with a trained attendant either visually, via
phone, or by two-way radio. This enables a quick rescue if anything were to go
wrong, or for the attendant to order the worker in the confined space to
evacuate and to alert appropriately trainer rescue personnel to rescue entrants
when needed.