WAC 296-304-020
Confined and enclosed spaces and other
dangerous atmospheres in shipyard employment. Scope,
application and definitions applicable to this subsection:
(1) Scope and application. This section applies to work
in confined and enclosed spaces and other dangerous
atmospheres in shipyard employment, including vessels, vessel
sections, and on land-side operations regardless of geographic
location.
(2) Definitions applicable to this section:
Adjacent spaces means those spaces bordering a subject
space in all directions, including all points of contact,
corners, diagonals, decks, tank tops, and bulkheads.
Certified industrial hygienist (CIH) means an industrial
hygienist who is certified by the American Board of Industrial
Hygiene.
Coast Guard authorized person means an individual who
meets the requirement of WAC 296-304-02015, Appendix C, for
tank vessels, for passenger vessels, and for cargo and
miscellaneous vessels.
Dangerous atmosphere means an atmosphere that may expose
employees to the risk of death, incapacitation, impairment of
ability to self-rescue (i.e., escape unaided from a confined
or enclosed space), injury, or acute illness.
Director means the director of the department of labor
and industries or his/her designated representative.
Enter with restrictions denotes a space where entry for
work is permitted only if engineering controls, personal
protective equipment, clothing, and time limitations are as
specified by the marine chemist, certified industrial
hygienist, or the shipyard competent person.
Entry means the action by which a person passes through
an opening into a space. Entry includes ensuing work
activities in that space and is considered to have occurred as
soon as any part of the entrant's body breaks the plane of an
opening into the space.
Hot work means any activity involving riveting, welding,
burning, the use of powder-actuated tools or similar
fire-producing operations. Grinding, drilling, abrasive
blasting, or similar spark-producing operations are also
considered hot work except when such operations are isolated
physically from any atmosphere containing more than 10 percent
of the lower explosive limit of a flammable or combustible
substance.
Immediately dangerous to life or health (IDLH) means an
atmosphere that poses an immediate threat to life or that is
likely to result in acute or immediate severe health effects.
Inert or inerted atmosphere means an atmospheric
condition where:
(a) The oxygen content of the atmosphere in the space is
maintained at a level equal to or less than 8.0 percent by
volume or at a level at or below 50 percent of the amount
required to support combustion, whichever is less; or
(b) The space is flooded with water and the vapor
concentration of flammable or combustible materials in the
free space atmosphere above the water line is less than 10
percent of the lower explosive limit for the flammable or
combustible material.
Labeled means identified with a sign, placard, or other
form of written communication, including pictograms, that
provides information on the status or condition of the work
space to which it is attached.
Lower explosive limit (LEL) means the minimum
concentration of vapor in air below which propagation of a
flame does not occur in the presence of an ignition source.
Marine chemist means an individual who possesses a
current marine chemist certificate issued by the National Fire
Protection Association (NFPA).
NFPA means National Fire Protection Association.
Nationally Recognized Testing Laboratory (NRTL) means an
organization recognized by OSHA, in accordance with Appendix A
of 29 CFR 1910.7, which tests for safety and lists or labels
or accepts equipment and materials that meet all the criteria
found in Section 1910.7 (b)(1) through (b)(4)(ii).
Not safe for hot work denotes a space where hot work may
not be performed because the conditions do not meet the
criteria for "safe for hot work."
Not safe for workers denotes a space where an employee
may not enter because the conditions do not meet the criteria
for "safe for workers."
Oxygen-deficient atmosphere means an atmosphere having an
oxygen concentration of less than 19.5 percent by volume.
Oxygen-enriched atmosphere means an atmosphere that
contains 22.0 percent or more oxygen by volume.
Safe for hot work denotes a space that meets all of the
following criteria:
(a) The oxygen content of the atmosphere does not exceed
22.0 percent by volume;
(b) The concentration of flammable vapors in the
atmosphere is less than 10 percent of the lower explosive
limit;
(c) The residues or materials in the space are not
capable of producing a higher concentration than permitted in
(a) or (b) of the above, under existing atmospheric conditions
in the presence of hot work and while maintained as directed
by the marine chemist or competent person; and
(d) All adjacent spaces have been cleaned, or inerted, or
treated sufficiently to prevent the spread of fire.
Safe for workers denotes a space that meets the following
criteria:
(a) The oxygen content of the atmosphere is at least 19.5
percent and below 22.0 percent by volume;
(b) The concentration of flammable vapors is below 10
percent of the lower explosive limit (LEL);
(c) Any toxic materials in the atmosphere associated with
cargo, fuel, tank coatings, or inerting media are within
permissible concentrations at the time of the inspection; and
(d) Any residues or materials associated with the work
authorized by the marine chemist, certified industrial
hygienist, or competent person will not produce uncontrolled
release of toxic materials under existing atmospheric
conditions while maintained as directed.
Space means an area on a vessel or vessel section or
within a shipyard such as, but not limited to: Cargo tanks or
holds; pump or engine rooms; storage lockers; tanks containing
flammable or combustible liquids, gases, or solids; rooms
within buildings; crawl spaces; tunnels; or accessways. The
atmosphere within a space is the entire area within its
bounds.
Upper explosive limit (UEL) means the maximum
concentration of flammable vapor in air above which
propagation of flame does not occur on contact with a source
of ignition.
Vessel section means a subassembly, module, or other
component of a vessel being built, repaired, or broken.
Visual inspection means the physical survey of the space,
its surroundings and contents to identify hazards such as, but
not limited to, restricted accessibility, residues, unguarded
machinery, and piping or electrical systems.
[Statutory Authority: RCW 49.17.010, 49.17.040, 49.17.050,
49.17.060. 07-17-034, § 296-304-020, filed 8/7/07, effective
12/1/07. Statutory Authority: Chapter 49.17 RCW. 95-04-006,
§ 296-304-020, filed 1/18/95, effective 3/10/95; 93-04-111
(Order 92-15), § 296-304-020, filed 2/3/93, effective 3/15/93;
Order 74-25, § 296-304-020, filed 5/7/74.]