(1) Prior to permitting employees to start demolition operations, an
engineering survey shall be made, by a competent person, of the structure
to determine structural integrity and the possibility of unplanned collapse
of any portion of the structure. Any adjacent structure where employees
may be exposed shall also be similarly checked. The employer shall have
in writing, evidence that such a survey has been performed.
(2) A copy of the survey report and of the plans and/or methods of operations
shall be maintained at the job site for the duration of the demolition
operation.
(3) Any device or equipment such as scaffolds, ladders, derricks, hoists,
etc., used in connection with demolition work shall be constructed, installed,
inspected, maintained and operated in accordance with the regulations
governing the construction, installation, inspection, maintenance and
operation of such device or equipment as specified in other parts of this
chapter.
(4) Federal and state codes, safety standards, rules, regulations, and
ordinances governing any and all phases of demolition work shall be observed
at all times.
(5) Demolition of all buildings and structures shall be conducted under
competent supervision, and safe working conditions shall be afforded the
employees.
(6) When employees are required to work within a structure to be demolished
which has been damaged by fire, flood, explosion, or other cause, the
walls or floor shall be shored or braced.
(7) All electric, gas, water, steam, sewer, and other service lines shall
be shut off, capped, or otherwise controlled, outside the building line
before demolition work is started. In each case, any utility company which
is involved shall be notified in advance.
(8) If it is necessary to maintain any power, water or other utilities
during demolition, such lines shall be temporarily relocated, as necessary,
and protected.
(9) It shall be determined whether asbestos, hazardous materials,
hazardous chemicals, gases, explosives, flammable materials, or
similarly dangerous substances are present at the work site. When
the presence of any such substance is apparent or suspected, testing
and removal or purging shall be performed and the hazard eliminated
before demolition is started. Removal of such substances shall
be in accordance with the requirements of chapters
296-62 and 296-65
WAC.
(10) Where a hazard exists from fragmentation of glass, such hazards
shall be removed.
(11) Where a hazard exists to employees falling through wall openings,
the opening shall be protected to a height of between thirty-six and forty-two
inches.
(12) When debris is dropped without the use of chutes, the area onto
which the material is dropped shall be completely enclosed with barricades
not less than forty-two inches high and not less than twenty feet back
from the projected edge of the opening above. Signs, warning of the hazard
of falling materials, shall be posted at each level. Removal shall not
be permitted in this lower area until debris handling ceases above.
(13) All floor openings, not used as material drops, shall be covered
over with material substantial enough to support the weight of any load
which may be imposed. Such material shall be properly secured to prevent
its accidental movement.
(14) Except for the cutting of holes in floors for chutes, holes through
which to drop materials, preparation of storage space, and similar necessary
preparatory work, the demolition of exterior walls and floor construction
shall begin at the top of the structure and proceed downward. Each story
of exterior wall and floor construction shall be removed and dropped into
the storage space before commencing the removal of exterior walls and
floors in the story next below.
(15) Workers shall not be permitted to carry on a demolition operation
which will expose persons working on a lower level to danger.
(16) Employee entrances to multistory structures being demolished shall
be completely protected by sidewalk sheds or canopies, or both, providing
protection from the face of the building for a minimum of eight feet.
All such canopies shall be at least two feet wider than the building entrances
or openings (one foot wider on each side thereof), and shall be capable
of sustaining a load of one hundred fifty pounds per square foot.
(17) Protruding nails in boards, planks and timber shall be withdrawn,
driven in or bent over as soon as the same is removed from the structure
being demolished.
(18) Any material to be removed which will cause dust to be formed, shall
be sprinkled with water to lay the dust incidental to its removal.
(1) Only those stairways, passageways, and ladders, designated as means
of access to the structure of building, shall be used. Other access ways
shall be entirely closed off at all times.
(2) All stairs, passageways, ladders and incidental equipment thereto,
which are covered by this section, shall be periodically inspected and
maintained in a clean safe condition.
(3) All ladders shall be secured in position.
(4) In a multistory building, when a stairwell is being used, it shall
be properly illuminated by either natural or artificial means, and completely
and substantially covered over at a point not less than two floors below
the floor on which work is being performed. Access to the floor where
the work is in progress shall be through a properly lighted, protected,
and separate passageway.
(1) No material shall be dropped to any point lying outside the exterior
walls of the structure unless the area is effectively protected.
(2) All materials chutes, or sections thereof, at an angle of more than
45° from the horizontal, shall be entirely enclosed, except for openings
equipped with closures at or about floor level for the insertion of materials.
The openings shall not exceed 48 inches in height measured along the wall
of the chute. At all stories below the top floor, such openings shall
be kept closed when not in use.
(3) A substantial gate shall be installed in each chute at or near the
discharge end. A competent employee shall be assigned to control the operation
of the gate, and the backing and loading of trucks.
(4) When operations are not in progress, the area surrounding the discharge
end of a chute shall be securely closed off.
(5) Any chute opening, into which workers dump debris, shall be protected
by a substantial guardrail between 36 and 42 inches above the floor or
other surface on which the employees stand to dump the material. Any space
between the chute and the edge of openings in the floors through which
it passes shall be solidly covered over.
(6) Where the material is dumped from mechanical equipment or wheelbarrows,
a securely attached toeboard or bumper, not less than 4 inches thick and
6 inches high, shall be provided at each chute opening.
(7) Chutes shall be designed and constructed of such strength as to eliminate
failure due to impact of materials or debris loaded therein.
WAC 296-155-790 Removal
of materials through floor openings.
Any openings cut in a floor for the disposal of materials shall be no
larger in size than 25 percent of the aggregate of the total floor area,
unless the lateral supports of the removed flooring remain in place. Floors
weakened or otherwise made unsafe by demolition operations shall be shored
to carry safely the intended imposed load from demolition operations.
WAC 296-155-795
Removal of walls, masonry sections, and chimneys.
(1) Masonry walls, or other sections of masonry, shall not be permitted
to fall upon the floors of the building in such masses as to exceed the
safe carrying capacities of the floors.
(2) No wall section, which is more than one story in height, shall be
permitted to stand alone without lateral bracing, unless such wall was
originally designed and constructed to stand without such lateral support,
and is in a condition safe enough to be self-supporting. All walls shall
be left in a stable condition at the end of each shift.
(3) Employees shall not be permitted to work on the top of a wall when
weather conditions constitute a hazard.
(4) Structural or load-supporting members on any floor shall
not be cut or removed until all stories above such a floor have
been demolished and removed. This provision shall not prohibit
the cutting of floor beams for the disposal of materials or for
the installation of equipment, provided that the requirements
of WAC
296-155-790 and 296-155-800
are met.
(5) Floor openings within 10 feet of any wall being demolished shall
be planked solid, except when employees are kept out of the area below.
(6) In buildings of “skeleton-steel” construction, the steel framing
may be left in place during the demolition of masonry. Where this is done,
all steel beams, girders, and similar structural supports shall be cleared
of all loose material as the masonry demolition progresses downward.
(7) Walkways or ladders shall be provided to enable employees to safely
reach or leave any scaffold or wall.
(8) Walls, which serve as retaining walls to support earth or adjoining
structures, shall not be demolished until such earth has been properly
braced or adjoining structures have been properly underpinned.
(9) Walls, which are to serve as retaining walls against which debris
will be piled, shall not be so used unless capable of safely supporting
the imposed load.
(1) Openings cut in a floor shall extend the full span of the arch between
supports.
(2) Before demolishing any floor arch, debris and other material shall
be removed from such arch and other adjacent floor area. Planks not less
than 2 inches by 10 inches in cross section, full size undressed, shall
be provided for, and shall be used by employees to stand on while breaking
down floor arches between beams. Such planks shall be so located as to
provide a safe support for the workers should the arch between the beams
collapse. The open space between planks shall not exceed 16 inches.
(3) Safe walkways, not less than 18 inches wide, formed of planks not
less than 2 inches thick if wood, or of equivalent strength if metal,
shall be provided and used by workers when necessary to enable them to
reach any point without walking upon exposed beams.
(4) Stringers of ample strength shall be installed to support the flooring
planks, and the ends of such stringers shall be supported by floor beams
or girders, and not by floor arches alone.
(5) Planks shall be laid together over solid bearings with the ends overlapping
at least 1 foot.
(6) When floor arches are being removed, employees shall not be allowed
in the area directly underneath, and such an area shall be barricaded
to prevent access to it.
(7) Demolition of floor arches shall not be started until they, and the
surrounding floor area for a distance of 20 feet, have been cleared of
debris and any other unnecessary materials.
WAC 296-155-805 Removal
of walls, floors, and material with equipment.
(1) Mechanical equipment shall not be used on floors or working surfaces
unless such floors or surfaces are of sufficient strength to support the
imposed load.
(2) Floor openings shall have curbs or stop-logs to prevent equipment
from running over the edge.
(3) Mechanical equipment used shall meet the requirements specified in
parts L and M of this chapter.
(1) During the demolition of the exterior walls of a structure originally
more than seventy feet high, catch platforms shall be erected along the
exterior faces of such walls where necessary to prevent injury to persons
working below.
(2) Such catch platforms shall be constructed and maintained not more
than three stories below the story from which the exterior walls are being
removed, until the demolition has progressed to within three stories of
the ground level.
(3) Catch platforms shall not be less than five feet in width measured
in a horizontal distance from the face of the structure and constructed
of outriggers and planks. Planks shall be laid tight together and without
openings between the planks and the wall.
Note: Catch platforms may be constructed of other
approved materials of equal strength and security against falling material.
(4) Catch platforms shall be capable of sustaining a uniform live load
of not less than one hundred and twenty-five pounds per square foot.
(1) The storage of waste material and debris on any floor shall not exceed
the allowable floor loads.
(2) In buildings having wooden floor construction, the flooring boards
may be removed from not more than one floor above grade to provide storage
space for debris, provided falling material is not permitted to endanger
the stability of the structure.
(3) When wood floor beams serve to brace interior walls or free-standing
exterior walls, such beams shall be left in place until other equivalent
support can be installed to replace them.
(4) Floor arches, to an elevation of not more than 25 feet above grade,
may be removed to provide storage area for debris: Provided, That such
removal does not endanger the stability of the structure.
(5) Storage space into which material is dumped shall be blocked off,
except for openings necessary for the removal of material. Such openings
shall be kept closed at all times when material is not being removed.
(1) When floor arches have been removed, planking in accordance with
WAC
296-155-800(2) shall be provided for the workers engaged in
razing the steel framing.
(2) Cranes, derricks, and other hoisting equipment used shall meet the
requirements specified in part
L of this chapter.
(3) Steel construction shall be dismantled column length by column length,
and tier by tier (columns may be in two-story lengths).
(4) Any structural member being dismembered shall not be overstressed.
(1) No workers shall be permitted in any area, which can be adversely
affected by demolition operations, when balling or clamming is being performed.
Only those workers necessary for the performance of the operations shall
be permitted in this area at any other time.
(2) The weight of the demolition ball shall not exceed 50 percent of
the crane's rated load, based on the length of the boom and the maximum
angle of operation at which the demolition ball will be used, or it shall
not exceed 25 percent of the nominal breaking strength of the line by
which it is suspended, whichever results in a lesser value.
(3) The crane boom and loadline shall be as short as possible.
(4) The ball shall be attached to the loadline with a swivel-type connection
to prevent twisting of the loadline, and shall be attached by positive
means in such manner that the weight cannot become accidentally disconnected.
(5) When pulling over walls or portions thereof, all steel members affected
shall have been previously cut free.
(6) All roof cornices or other such ornamental stonework shall be removed
prior to pulling walls over.
(7) During demolition, continuing inspections by a competent person shall
be made as the work progresses to detect hazards resulting from weakened
or deteriorated floors, or walls, or loosened material. No employee shall
be permitted to work where such hazards exist until they are corrected
by shoring, bracing, or other effective means.
For
printing