WAC
296-155-675 Scope, application, and definitions applicable
to this part.
(1) Scope and application. This part sets forth requirements
to protect all construction employees from the hazards associated
with concrete and masonry construction operations performed in
workplaces covered under chapter
296-155 WAC.
(2) Definitions applicable to this part.
(a) “Bull float” means a tool used to spread
out and smooth the concrete.
(b) “Formwork” means the total system of
support for freshly placed or partially cured concrete, including
the mold or sheeting (form) that is in contact with the concrete
as well as all supporting members including shores, reshores,
hardware, braces, and related hardware.
(c) “Jacking operation” means the task
of lifting a slab (or group of slabs) vertically from one location
to another (e.g., from the casting location to a temporary (parked)
location, or from a temporary location to another temporary
location, or to its final location in the structure), during
the construction of a building/structure where the lift-slab
process is being used.
(d) “Lift slab” means a method of concrete
construction in which floor and roof slabs are cast on or at
ground level and, using jacks, lifted into position.
(e) “Limited access zone” means an area
alongside a masonry wall, which is under construction, and which
is clearly demarcated to limit access by employees.
(f) “Precast concrete” means concrete members
(such as walls, panels, slabs, columns, and beams) which have
been formed, cast, and cured prior to final placement in a structure.
(g) “Reshoring” means the construction
operation in which shoring equipment (also called reshores or
reshoring equipment) is placed, as the original forms and shores
are removed, in order to support partially cured concrete and
construction loads.
(h) “Shore” means a supporting member
that resists a compressive force imposed by a load.
(i) “Vertical slip forms” means forms which
are jacked vertically during the placement of concrete.
(j) “Guy” means a line that steadies a
high piece or structure by pulling against an off-center load.
(1) General. All equipment, material and construction techniques
used in concrete construction and masonry work shall meet the
applicable requirements for design, construction, inspection,
testing, maintenance and operations as prescribed in ANSI A10.9-1970,
Safety Requirements for Concrete Construction and Masonry Work.
(2) Construction loads. No construction loads shall be placed
on a concrete structure or portion of a concrete structure unless
the employer determines, based on information received from a
person who is qualified in structural design, that the structure
or portion of the structure is capable of supporting the loads.
(3) Vertical loads. Vertical loads consist of a dead load plus
an allowance for live load. The weight of formwork together with
the weight of freshly placed concrete is dead load. The live load
consists of the weight of workers, equipment, runways and impact,
and shall be computed in pounds per square foot (psf) of horizontal
projection.
(4) Lateral loads. Braces and shores shall be designed to resist
all foreseeable lateral loads such as wind, cable tensions, inclined
supports, impact of placement, and starting and stopping of equipment.
The assumed value of load due to wind, impact of concrete, and
equipment acting in any direction at each floor line shall not
be less than one hundred pounds per lineal foot of floor edge
or two percent of total dead load of the floor, whichever is greater.
Wall forms shall be designed for a minimum wind load of ten psf,
and bracing for wall forms should be designed for a lateral load
of at least one hundred pounds per lineal foot of wall, applied
at the top. Walls of unusual height require special consideration.
(5) Special loads. Formwork shall be designed for all special
conditions of construction likely to occur, such as unsymmetrical
placement of concrete, impact of machine-delivered concrete, uplift,
and concentrated loads.
(6) Form supports and wedges shall be checked during concrete
placement to prevent distortion or failure.
(7) Reinforcing steel.
(a) All protruding reinforcing steel, onto and into which employees
could fall, shall be guarded to eliminate the hazard of impalement.
(b) Wire mesh rolls: Wire mesh rolls shall be secured at each
end to prevent dangerous recoiling action.
(c) Guying: Reinforcing steel for walls, piers, columns, and
similar vertical structures shall be guyed and supported to
prevent overturning and to prevent collapse.
(8) Post-tensioning operations.
(a) No employee (except those essential to the post-tensioning
operations) shall be permitted to be behind the jack during
tensioning operations.
(b) Signs and barriers shall be erected to limit employee access
to the post-tensioning area during tensioning operations.
(9) Working under loads.
(a) No employee shall be permitted to work under concrete buckets
while buckets are being elevated or lowered into position.
(b) To the extent practical, elevated concrete buckets shall
be routed so that no employee, or the fewest number of employees,
are exposed to the hazards associated with falling concrete
buckets.
(10) Personal protective equipment.
(a) No employee shall be permitted to apply a cement, sand,
and water mixture through a pneumatic hose unless the employee
is wearing protective head and face equipment.
(b) No employee shall be permitted to place or tie reinforcing
steel more than six feet (1.8 m) above any adjacent working
surface unless the employee is protected by personal fall arrest
systems, safety net systems, or positioning device systems meeting
the criteria of chapter
296-155 WAC, Part C-1.
(c) Each employee on the face of formwork or reinforcing steel
shall be protected from falling 6 feet (1.8m) or more to lower
levels by personal fall arrest systems, safety net systems,
or positioning device systems meeting the criteria of chapter
296-155 WAC, Part C-1.
WAC
296-155-681 Safe walking surfaces on concrete structural members.
Structural members with studs, dowels, or shear connectors installed
on the top side shall not be used as a walkway and/or means of
access unless such studs, dowels, or shear connectors are covered
with suitable material and in such a manner as to provide a walking
surface at least as stable and free of hazards as the top surface
of the member would provide without attachments installed.
Note: For the purpose of this section,
“stud” means all protruding metal attachments
to structural members.
(1) Bulk cement storage. Bulk storage bins, containers, and silos
shall be equipped with the following:
(a) Conical or tapered bottoms; and
(b) Mechanical or pneumatic means of starting the flow of material.
(2) No employee shall be permitted to enter storage facilities
unless the ejection system has been shut down and locked out in
accordance with WAC
296-155-429.
(3) Safety belts, harnesses, lanyards, lifelines or droplines,
independently attached or attended, shall be used as prescribed
in chapter
296-155 WAC, Part C-1.
(4) Concrete mixers. Concrete mixers with one cubic yard (.8
m3) or larger loading skips shall be equipped with the following:
(a) A mechanical device to clear the skip of materials; and
(b) Guardrails installed on each side of the skip.
(5) Power concrete trowels. Powered and rotating type concrete
troweling machines that are manually guided shall be equipped
with a control switch that will automatically shut off the power
whenever the hands of the operator are removed from the equipment
handles.
(6) Concrete buggies. Concrete buggy handles shall not extend
beyond the wheels on either side of the buggy.
Note: Installation of knuckle guards on
buggy handles is recommended.
(7) Runways.
(a) Runways shall be constructed to carry the maximum contemplated
load with a safety factor of four, have a smooth running surface,
and be of sufficient width for two buggies to pass. Single runs
to have a minimum width of forty-two inches with turnouts. Runways
to have standard railings. Where motor driven concrete buggies
are used, a minimum four-inches by four-inches wheel guard shall
be securely fastened to outside edge of runways.
(b) All concrete buggy runways which are 12 inches or more
above a work surface or floor, or ramps with more than 4 percent
incline shall be considered “elevated” runways.
Exception: Small jobs utilizing only one
concrete buggy, or larger jobs utilizing a “one-way traffic
pattern” may be exempt from the requirements for “turnouts”
or for” sufficient width for two buggies to pass.”
Exemption: Runways less than 12 inches above
the floor or ground which are utilized by hard-powered buggies
only, may be exempt from the requirements for guardrails and wheelguards.
(8) Concrete pumps and placing booms.
(a) Definitions.
“Concrete delivery hose” means a flexible
concrete delivery hose which has two end couplings.
“Concrete pump” means a construction machine
that pumps concrete.
“Controls” means the devices used to operate
a machine.
“Delivery systems” means the pipe, hoses and
components, through which the concrete is pumped.
“Grooved end” means a pipe clamp pipe connection
where a groove is machined or rolled directly into the outside
of the pipe wall (for example: Victualic).
“Material pressure” means the pressure exerted
on the concrete inside the delivery system.
“Placing boom and placing unit” means a manual
or power driven, slewable working device which:
Consists of one or more extendable or folding parts for
supporting the concrete delivery system, and directs the discharge
into the desired location; and
May be mounted on trucks, trailers, or special vehicles.
“Qualified person” means someone who:
Possesses a recognized degree or certificate of professional
standing; or
Has extensive knowledge, training, and experience; or
Successfully demonstrated the ability to resolve problems
relating to the work.
“Restraining devices” means a sling, cable,
or equivalent device used to minimize excess movement of a delivery
system in case of separation.
“Whip hoses” means a suspended hose that has
only one coupling and is used to direct the delivery of concrete.
(b) Equipment requirements.
(i) Equipment identification tag.
The employer must ensure the following identification is
furnished if originally identified by the manufacturer and
on all pumps manufactured after January 1, 1998:
The manufacturer's name;
The year of manufacture;
The model and serial number;
The maximum material pressure;
The maximum allowable pressure in the hydraulic system;
and
The maximum weight per foot of delivery system including
concrete.
(ii) Manufacturer's manual.
The employer must have the manufacturer's operation/safety
manual or equivalent available for each concrete pump or placing
boom.
(iii) Unsafe condition of equipment.
If during an equipment inspection a condition is revealed
that might endanger workers, the equipment must not be returned
to service until the condition is corrected.
(iv) Controls.
Controls must have their function clearly marked.
(v) Hydraulic systems.
(A) Concrete pumps and placing booms hydraulic systems
must have pressure relief valves to prevent cylinder and
boom damage.
(B) Hydraulic systems must have hydraulic holding valves
if hose or coupling failure could result in uncontrolled
vertical movement
(iv) Certification.
In the event of failure of a structural member, overloading,
or contact with energized electric power lines and before
return to service, the equipment must be certified safe by:
The manufacturer; or
An agent of the manufacturer; or
A professional engineer.
(vii) Marking weight. A permanent, legible notice stating
the total weight of the unit must be marked on:
Trailer or skid mounted concrete pumps;
Placing booms; and
All major detachable components over five hundred pounds.
(viii) Lifting a pump.
A concrete pump must be lifted using the lift points specified
by the manufacturer or a professional engineer.
(ix) Emergency shutoff.
A concrete pump must have a clearly labeled emergency stop
switch that stops the pumping action.
(x) Inlet and outlet guarding.
(A) The waterbox must have a fixed guard to prevent unintentional
access to the moving parts.
(B) The agitator must be guarded with a point of operation
guard in accordance with chapter
296-806 WAC, Machine safety, and the guard must be:
Hinged or bolted in place;
At least three inches distance from the agitator;
Be capable of supporting a load of two hundred fifty
pounds.
(C) A person must not stand on the guard when the pump
or agitator is running.
(xi) Outriggers.
(A) Outriggers must be used in accordance with the manufacturer's
specifications.
(B) Concrete pump trucks manufactured after January 1,
1998, must have outriggers or jacks permanently marked to
indicate the maximum loading they transmit to the ground.
(xii) Load on a placing boom.
(A) The manufacturer's or a licensed, registered, structural
engineer's specifications for the placing boom must not
be exceeded by:
The weight of the load;
The length and diameter of suspended hose;
The diameter and weight of mounted pipe.
(B) A concrete placing boom must not be used to drag hoses
or lift other loads.
(C) All engineering calculations regarding modifications
must be:
Documented;
Recorded; and
Available upon request.
(xiii) Pipe diameter thickness. The pipe wall thickness must
be measured in accordance with the manufacturer's instruction,
and:
Be sufficient to maintain a burst pressure greater than
the maximum pressure the pump can produce;
The pipe sections must be replaced when measurements
indicate wall thickness has been reduced to the limits
specified by the manufacturer.
(xiv) Pipe clamps.
(A) Concrete must not be pumped through a delivery system
with grooved ends, such as those for Victualic-type couplers.
(B) Pipe clamps must have a pressure rating at least equal
to the pump pressure rating.
(C) Pipe clamps contact surfaces must be free of concrete
and other foreign matter.
(D) If quick connect clamps are used, they must be pinned
or secured to keep them from opening when used in a vertical
application.
(xv) Delivery pipe.
(A) A delivery pipe between the concrete pump and the placing
system must be supported and anchored to prevent movement
and excessive loading on clamps.
(B) Double ended hoses must not be used as whip hoses.
(C) Attachments must not be placed on whip hoses (i.e.,
“S” hooks, valves, etc.).
Table 1. Nonmandatory recommended maximum yards
per hour through hose
Hose Diameter
Hose Length (12'
and less) Max. yards per hour
Hose Length (12'
and longer) Max. yards per hour
2”
30
30
3”
90
50
4”
160
110
5”
See
Manufacturer specs
See
manufacturer specs
The above figures are based on a minimum of a 4”
slump and a 5 sack mix.
Variables in mix design can have an effect on these
ratings.
Aggregate should not exceed 1/3 the diameter on these
delivery system.
(xvi) Restraining. A restraining device must:
Be used on attachments suspended from the boom tips; and
Have a load rating not less than one-fifth of its ultimate
breaking strength.
(xvii) Equipment inspection.
(A) An inspection must be conducted annually for the first
five years and semiannually thereafter and must include
the following:
Nondestructive testing of all sections of the boom by
a method capable of ensuring the structural integrity
of the boom;
Be conducted by a qualified person or by a private agency.
(B) The inspection report must be documented and a copy
maintained by the employer and in each unit inspected. It
must contain the following:
The identification, including the serial numbers and
manufacturer's name, of the components and parts inspected
and tested;
A description of the test methods and results;
The names and qualifications of the people performing
the inspection;
A listing of necessary repairs; and
The signature of the manufacturer, an agent of the manufacturer,
or a qualified person.
Note: See WAC 296-155-628(8)(d) for the
inspection worksheet criteria.
(xviii) Equipment repair.
(A) Replacement parts must meet or exceed the original
manufacturer's specifications or be certified by a registered
professional structural engineer.
(B) A properly certified welder must perform any welding
on the boom, outrigger, or structural component.
(xix) Compressed air cleaning of the piping system. To clean
the piping system:
(A) The pipe system must be securely anchored before it
is cleaned out.
(B) The flexible discharge hose must be removed.
(C) Workers not essential to the cleaning process must
leave the vicinity.
(D) The compressed air system must have a shutoff valve.
(E) Blow out caps must have a bleeder valve to relieve
air pressure.
(F) A trap basket or containment device (i.e., concrete
truck, concrete bucket) must be available and secured to
receive the clean out device.
(G) Delivery pipes must be depressurized before clamps
and fittings are released.
(c) Qualifications and training requirements.
(i) Operator trainee-Qualification requirements. To be qualified
to become a concrete pump operator, the trainee must meet
the following requirements unless it can be shown that failure
to meet the requirements will not affect the operation of
the concrete pump boom.
(A) Vision requirements:
At least 20/30 Snellen in one eye and 20/50 in the other.
Corrective lenses may be used to fulfill this requirement;
Ability to distinguish colors, regardless of position,
if color differentiation is required;
Normal depth perception and field of vision.
(B) Hearing requirements. Hearing adequate to meet operational
demands. Corrective devices may be used to fulfill this
requirement.
(ii) Operator trainee-Training requirements. Operator trainee
training requirements include, but are not limited to, the
following:
(A) Demonstrated their ability to read and comprehend the
pump manufacturer's operation and safety manual.
(B) Be of legal age to perform the duties required.
(C) Received documented classroom training and testing
(as applicable) on these recommended subjects:
Driving, operating, cleaning and maintaining concrete
pumps, placing booms, and related equipment;
Jib/boom extensions;
Boom length/angle;
Manufacturer's variances;
Radii;
Range diagram, stability, tipping axis; and
Structural/tipping determinations.
(D) Maintain and have available upon request a copy of
all training materials and a record of training.
(E) Satisfactorily complete a written examination for the
concrete pump boom for which they are becoming qualified.
It will cover:
Safety;
Operational characteristics and limitations; and
Controls.
(iii) Operator-Qualifications requirements. Operators will
be considered qualified when they have:
(A) Completed the operator trainee requirements listed
in (c)(i) and (ii) of this subsection.
(B) Completed a program of training conducted by a qualified
person, including practical experience under the direct
supervision of a qualified person.
(C) Passed a practical operating examination of their ability
to operate a specific model and type of equipment. Possess
the knowledge and the ability to implement emergency procedures.
(D) Possess the knowledge regarding the restart procedure
after emergency stop has been activated.
(E) Possess the proper class of driver's license to drive
the concrete pump truck.
(F) Demonstrate the ability to comprehend and interpret
all labels, safety decals, operator's manuals, and other
information required to safely operate the concrete pump.
(G) Be familiar with the applicable safety requirements.
(H) Understand the responsibility for equipment maintenance.
(d) Concrete pump inspection worksheet criteria. Concrete pump
trucks will be inspected using the following criteria: The manufacturer's
required inspection criteria will be followed in all instances.
Note: DOT requirements for inspections-Ref.
49 C.F.R. 396.11, Driver Vehicle Inspections and 396.13, Driver
Pre-Trip Inspections; and WAC
296-155-610.
(i) Hydraulic systems.
(A) Oil level;
(B) Hoses;
(C) Fittings;
(D) Holding valves;
(E) Pressure settings;
(F) Hydraulic cylinders;
(G) Ensure that the emergency stop system is functioning
properly;
(H) All controls clearly marked.
(ii) Electrical.
(A) All systems functioning properly.
(B) All remote control functions are operating properly.
Ensure that the emergency stop system is functioning properly.
(C) All controls clearly marked.
(iii) Structural.
(A) Visual inspection for cracks, corrosion, and deformations
of the concrete pump with placing boom structure, and all
load carrying components such as outriggers, cross frames,
torsion box beams, and delivery line support structures
that may lead to nondestructive testing.
(B) Visual examination of all links, pivots, pins, and
bolts.
(C) Vertical and horizontal movement at the turret, turntable,
rotation gear lash, bearing tolerances, not to exceed manufacturer's
specifications.
(iv) Piping systems.
(A) Wall thickness must not exceed original manufacturer's
specifications.
(B) Mounting hardware for attaching delivery system.
(C) Correct clamps and safety pins.
(v) Safety decals.
All safety decals shall be in place as required by the
manufacturer.
(9) Concrete buckets.
(a) Concrete buckets equipped with hydraulic or pneumatic gates
shall have positive safety latches or similar safety devices
installed to prevent premature or accidental dumping.
(b) Concrete buckets shall be designed to prevent concrete
from hanging up on top and the sides.
(c) Riding of concrete buckets for any purpose shall be prohibited,
and vibrator crews shall be kept out from under concrete buckets
suspended from cranes or cableways.
(d) When discharging on a slope, the wheels of ready-mix trucks
shall be blocked and the brakes set to prevent movement.
(10) Tremies. Sections of tremies and similar concrete conveyances
shall be secured with wire rope (or equivalent materials in addition
to the regular couplings or connections).
(11) Bull floats. Bull float handles, used where they might contact
energized electrical conductors, shall be constructed of nonconductive
material or insulated with a nonconductive sheath whose electrical
and mechanical characteristics provide the equivalent protection
of a handle constructed of nonconductive material.
(12) Masonry saws shall be constructed, guarded, and operated
in accordance with WAC
296-155-367 (1) through (4).
(13) Lockout/tagout procedures. No employee shall be permitted
to perform maintenance or repair activity on equipment (such as
compressors, mixers, screens, or pumps used for concrete and masonry
construction activities) where the inadvertent operation of the
equipment could occur and cause injury, unless all potentially
hazardous energy sources have been locked out and tagged in accordance
with chapter
296-155 WAC, Part I.
(2) Where grinders, chippers, and other equipment is used which
creates a thrust force while working on scaffolding, such scaffold
shall be securely tied to a structure or held in with weighted
drop lines.
(3) Grinding and dressing operations carried on within closed
rooms, stairwells, elevator shafts, etc., shall be provided with
forced air ventilation.
(4) Grinding machine operators shall wear respirators whenever
machines are in operation or where dust hazard exists.
(5) Eye protection shall be worn by workers engaged in grinding,
chipping, or sacking concrete as required by WAC
296-155-215.
(a) Formwork shall be designed, fabricated, erected, supported,
braced, and maintained so that it will be capable of supporting
without failure all vertical and lateral loads that may reasonably
be anticipated to be applied to the formwork. Formwork which
is designed, fabricated, erected, supported, braced, and maintained
in conformance with the Appendix to this section will be deemed
to meet the requirements of this subdivision.
(b) Any form, regardless of size, shall be planned in every
particular and designed and constructed with an adequate factor
of safety. In addition to computable loading, additional form
pressures may result from impact during concrete placement,
sudden lowering of temperatures retarding the set and increasing
the liquid head or static pressure, vibrations of the form or
concrete, uneven stressing resulting from failure or weakening
of form members, or impact from concrete buckets or placing
equipment. As a result, an adequate factor of safety is required
to offset these unpredictable conditions.
(c) The thoroughness of planning and design shall be governed
by the size, complexity, and intended use of the form. Formwork
which is complex in nature or which will be subjected to unusually
high concrete pressures shall be designed or approved for use
by an engineer or experienced form designer.
(2) Drawings or plans, including all revisions, for the jack
layout, formwork (including shoring equipment), working decks,
and scaffolds, shall be available at the jobsite.
(3) Shoring and reshoring.
(a) General: Shoring installations constructed in accordance
with this standard shall be designed in accordance with American
National Standard Recommended Practice for Concrete Formwork,
ANSI-(ACI 347-78), Formwork for Concrete ACI 318-83, or with
the following publications of the Scaffolding & Shoring
Institute: Recommended Standard Safety Code for Vertical Shoring,
1970; Single Post Shore Safety Rules, 1969; and Steel Frame
Shoring Safety, Safety Rules, 1969.
(b) All shoring equipment shall be inspected prior to erection
to determine that it is as specified in the shoring layout.
(c) A shoring layout shall be prepared or approved by a person
qualified to analyze the loadings and stresses which are induced
during the construction process.
(d) A copy of the shoring layout shall be available at the
jobsite.
(e) The shoring layout shall include all details of the specification,
including unusual conditions such as heavy beams, sloping areas,
ramps, and cantilevered slabs, as well as plan and elevation
views.
(f) Shoring equipment found to be damaged such that its strength
is reduced to less than that required by WAC
296-155-684 (1)(a) shall not be used for shoring.
(g) Erected shoring equipment shall be inspected immediately
prior to, during, and immediately after concrete placement.
(h) Upon inspection, shoring equipment that is found to be
damaged or weakened shall be immediately removed and replaced.
(i) The sills for shoring shall be sound, rigid, and capable
of carrying the maximum intended load without settlement or
displacement.
(j) All base plates, shore heads, extension devices, and adjustment
screws shall be in firm contact, and secured when necessary,
with the foundation and the form.
(k) Eccentric loads on shore heads and similar members shall
be prohibited unless these members have been designed for such
loading.
(l) The minimum total design load for any shoring used in slab
and beam structures shall be not less than one hundred pounds
per square foot for the combined live and dead load regardless
of slab thickness; however, the minimum allowance for live load
and formwork shall be not less than twenty pounds per square
foot in addition to the weight of the concrete. Additional allowance
for live load shall be added for special conditions other than
when placing concrete for standard-type slabs and beams. Shoring
shall also be designed to resist all foreseeable lateral loads
such as wind, cable tensions, inclined supports, impact of placement,
and starting and stopping of equipment. The assumed value of
load due to wind, impact of concrete, and equipment acting in
any direction at each floor line shall not be less than one
hundred pounds per lineal foot of floor edge or two percent
of total dead load of the floor, whichever is greater. (See
subsection (3)(b) of this section.)
(m) When motorized carts are used, the design load shall be
increased twenty-five pounds per square foot.
(4) The design stresses for form lumber and timbers shall be
within the tolerance of the grade, condition, and species of lumber
used.
(5) The design stresses used for form lumber and timber shall
be shown on all drawings, specifications, and shoring layouts.
(6) All load-carrying timber members of scaffold framing shall
be a minimum of 1500 f (stress grade) construction grade lumber.
All dimensions are nominal sizes except that where rough sizes
are noted, only rough or undressed lumber of the size specified
shall satisfy minimum requirements.
(7) When shoring from soil, an engineer or other qualified person
shall determine that the soil is adequate to support the loads
which are to be placed on it.
(8) Precautions shall be taken so that weather conditions do
not change the load-carrying conditions of the soil below the
design minimum.
(9) When shoring from fill or when excessive earth disturbance
has occurred, an engineer or other qualified person shall supervise
the compaction and reworking of the disturbed area and determine
that it is capable of carrying the loads which are to be imposed
upon it.
(10) Suitable sills shall be used on a pan or grid dome floor
or any other floor system involving voids where vertical shoring
equipment could concentrate an excessive load on a thin concrete
section.
(11) When temporary storage of reinforcing rods, material, or
equipment on top of formwork becomes necessary, these areas shall
be sufficient to meet the loads.
(12) If any deviation in the shoring plan is necessary because
of field conditions, the person who prepared the shoring layout
shall be consulted for approval of the actual field setup before
concrete is placed.
(13) The shoring setup shall be checked to insure that all details
of the layout have been met.
(14) The completed shoring setup shall be a homogenous unit or
units and shall have the specified bracing to give it lateral
stability.
(15) The shoring setup shall be checked to make certain that
bracing specified in the shoring layout for lateral stability
is in place.
(16) All vertical shoring equipment shall be plumb. Maximum allowable
deviation from the vertical is one-eighth inch in three feet.
If this tolerance is exceeded, the shoring equipment shall not
be used until readjusted within this limit.
(17) Upon inspection, shoring equipment that is found to be damaged
or weakened shall be immediately removed and replaced.
(18) Shoring equipment shall not be released or removed until
the approval of a qualified engineer has been received.
(19) Removal of shoring equipment shall be planned so that the
equipment which is still in place is not overloaded.
(20) Slabs or beams which are to be reshored should be allowed
to take their actual permanent deflection before final adjustment
of reshoring equipment is made.
(21) While the reshoring is underway, no construction loads shall
be permitted on the partially-cured concrete.
(22) The allowable load on the supporting slab shall not be exceeded
when reshoring.
(23) The reshoring shall be thoroughly checked to determine that
it is properly placed and that it has the load capacity to support
the areas that are being reshored.
(1) Metal tubular frames used for shoring shall have allowable
loads based on tests conducted according to the Recommended Procedure
for Compression Testing of Scaffolds and Shores, Scaffolding &
Shoring Institute, 1967.
(2) Design of shoring layouts shall be based on allowable loads
which were obtained using the test procedures of subsection (1)
of this section and on at least a two and one-half to one safety
factor.
(3) All metal frame shoring equipment shall be inspected before
erection.
(4) Metal frame shoring equipment and accessories shall not be
used if heavily rusted, bent, dented, rewelded, or having broken
weldments or other defects.
(5) All locking devices on frames and braces shall be in good
working order, coupling pins shall align the frame or panel legs,
pivoted cross braces shall have their center pivot in place, and
all components shall be in a condition similar to that of original
manufacture.
(6) When checking the erected shoring frames with the shoring
layout, the spacing between towers and cross-brace spacing shall
not exceed that shown on the layout, and all locking devices shall
be in the closed position.
(7) Devices for attaching the external lateral stability bracing
shall be securely fastened to the legs of the shoring frames.
(8) All baseplates, shore heads, extension devices, or adjustment
screws shall be in firm contact with the footing sill and the
form material, and shall be snug against the legs of the frames.
(9) Eccentric loads on shore heads and similar members shall
be prohibited unless the shore heads have been designed for such
loading.
(10) When formwork is installed at an angle, or sloping, or when
the surface shored from is sloping, the shoring shall be designed
for such loading.
(11) Adjustment screws shall not be adjusted to raise formwork
after the concrete is in place.
(1) Tube and coupler towers used for shoring shall have allowable
loads based on tests conducted according to the Recommended Procedure
for Compression Testing of Scaffolds and Shores, Scaffolding &
Shoring Institute, 1967.
(2) Design of shoring layouts shall be based on working loads
which were obtained using the test procedures of subsection (1)
of this section and on at least a two and one-half to one safety
factor.
(3) All tube and coupler components shall be inspected before
being used.
(4) Tubes of shoring structures shall not be used if heavily
rusted, bent, dented, or having other defects.
(5) Couplers (clamps) shall not be used if deformed, broken,
or having defective or missing threads on bolts, or other defects.
(6) The material used for the couplers (clamps) shall be of a
structural type such as drop-forged steel, malleable iron, or
structural grade aluminum. Gray cast iron shall not be used.
(7) When checking the erected shoring towers with the shoring
layout, the spacing between posts shall not exceed that shown
on the layout, and all interlocking of tubular members and tightness
of couplers should be checked.
(8) All baseplates, shore heads, extension devices, or adjustment
screws shall be in firm contact with the footing sill and the
form material, and shall be snug against the posts.
(9) Eccentric loads on shore heads and similar members shall
be prohibited unless the shore heads have been designed for such
loading.
(10) Special precautions shall be taken when formwork is at angles,
or sloping, or when the surface shored from is sloping.
(11) Adjustment screws shall not be adjusted to raise formwork
after the concrete is in place.
(1) When checking erected single post shores with the shoring
layout, the spacing between shores in either direction shall not
exceed that shown on the layout, and all clamps, screws, pins,
and all other components shall be in the closed or engaged position.
(2) For stability, single post shores shall be horizontally braced
in both the longitudinal and transverse directions. Diagonal bracing
shall also be installed. Such bracing shall be installed as the
shores are being erected.
(3) Devices which attach to the external lateral stability bracing
shall be securely fastened to the single post shores.
(4) All baseplates or shore heads of single post shores shall
be in firm contact with the footing sill and the form material.
(5) Whenever single post shores are used in more than one tier,
the layout shall be designed and inspected by a structural engineer.
(6) Eccentric loads on shore heads shall be prohibited unless
the shore heads have been designed for such loading.
(7) When formwork is at an angle, or sloping, or when the surface
shored from is sloping, the shoring shall be designed for such
loading.
(8) Adjustment of single post shores to raise formwork shall
not be made after concrete is in place.
(9) Respecting fabricated single post shores, the following shall
apply:
(a) The clamp used for adjustable timber single post shores
shall have working load ratings based on tests conducted according
to the standard test procedures for fabricated single post shores
in Recommended Procedure for Compression Testing of Scaffolds
and Shores, Scaffolding & Shoring Institute, 1967, and on
at least a three to one safety factor.
(b) Shoring layouts shall be made using working loads which
were obtained using the test procedures of (a) of this subsection,
and on at least a three to one safety factor.
(c) All fabricated single post shores shall be inspected before
being used.
(d) Fabricated single post shores shall not be used if heavily
rusted, bent, dented, rewelded, or having broken weldments or
other defects. If they contain timber, they shall not be used
if timber is split, cut, has sections removed, is rotted, or
otherwise structurally damaged.
(e) All clamps, screws, pins, threads, and all other components
shall be in a condition similar to that of original manufacture.
(10) Respecting adjustable timber single post shores, the following
shall apply:
(a) The clamp used for adjustable timber single post shores
shall have working load ratings based on tests conducted according
to the standard test procedures for fabricated single post shores
in Recommended Procedure for Compression Testing of Scaffolds
and Shores, Scaffolding & Shoring Institute, 1967, and on
at least a three to one safety factor.
(b) Timber used shall have the safety factor and allowable
working load for each grade and species as recommended in the
Tables for wooden columns in the Wood Structural Design Data
Book, National Forest Products Association, 1970.
(c) The shoring layout shall be made using the allowable load
obtained by using the test procedure for the clamp or Tables
for timber referred to in (a) and (b) of this subsection.
(d) All timber and adjusting devices to be used for adjustable
timber single post shores shall be inspected before erection.
(e) Timber shall not be used if it is split, cut, has sections
removed, is rotted, or is otherwise structurally damaged.
(f) Adjusting devices shall not be used if heavily rusted,
bent, dented, rewelded, or having broken weldments or other
defects.
(g) All nails used to secure bracing on adjustable timber single
post shores shall be driven home and the point of the nail bent
over.
(11) Respecting timber single post shores, the following shall
apply:
(a) Timber used as single post shores shall have the safety
factor and allowable working load for each grade and species
as recommended in the Tables for wooden columns in the Wood
Structural Design Data Book, National Forest Products Association,
1970.
(b) The shoring layout shall be prepared by using working loads
obtained by using the Tables referred to in (a) of this subsection.
(c) All timber to be used for single post shoring shall be
inspected before erection.
(d) Timber shall not be used if it is split, cut, has sections
removed, is rotted, or is otherwise structurally damaged.
(e) All nails used to secure bracing on timber single post
shores shall be driven home and the point of the nail bent over.
(12) Tiered single post shores. Whenever single post shores are
used one on top of another (tiered), the employer shall comply
with the following specific requirements in addition to the general
requirements for formwork:
(a) The design of the shoring shall be prepared by a qualified
designer and the erected shoring shall be inspected by an engineer
qualified in structural design.
(b) The single post shores shall be vertically aligned.
(c) The single post shores shall be spliced to prevent misalignment.
(d) The single post shores shall be adequately braced in two
mutually perpendicular directions at the splice level. Each
tier shall also be diagonally braced in the same two directions.
(e) Adjustment of single post shores to raise formwork shall
not be made after the placement of concrete.
(f) Reshoring shall be erected, as the original forms and shores
are removed, whenever the concrete is required to support loads
in excess of its capacity.
(1) Slip forms shall be designed and constructed, and the form
movement carried out, under the immediate supervision of a person
or persons experienced in slip form design and operation. Drawings
prepared by a qualified engineer, showing the jack layout, formwork,
working decks, and scaffolding, shall be available at the jobsite,
and followed.
(2) The steel rods or pipe on which the jacks climb or by which
the forms are lifted shall be designed for this purpose. Such
rods must be adequately braced where not encased in concrete.
(3) Forms shall be designed to prevent excessive distortion of
the structure during the jacking operation.
(4) All vertical slip forms shall be provided with scaffolding
or work platforms completely encircling the area of placement.
(5) Jacks and vertical supports shall be positioned in such a
manner that the loads do not exceed the rated capacity of the
jacks.
(6) The jacks or other lifting devices shall be provided with
mechanical dogs or other automatic holding devices to support
the slip forms whenever failure of the power supply or lifting
mechanism occurs.
(7) The form structure shall be maintained within all design
tolerances specified for plumbness during the jacking operation.
(8) Lifting shall proceed steadily and uniformly and shall not
exceed the predetermined safe rate of lift. A jacking system,
which provides precise, simultaneous movement of the entire form
in small preselected increments, is recommended for large structures.
(9) Workers placing reinforcing steel shall comply with the requirements
of chapter
296-155 WAC, Part C-1 when working above the scaffold level.
(10) The total allowable load on slip form platforms shall be
determined by the design engineer and enforced by the field supervisor.
(11) Lateral and diagonal bracing of the forms shall be provided
to prevent excessive distortion of the structure during the sliding
operation.
(12) While the slide is in operation, the form structure shall
be maintained in line and plumb.
(13) A field supervisor experienced in slip form construction
shall be present on the deck at all times.
(1) When moved or raised by crane, cableway, A-frame, or similar
mechanical device, forms shall be securely attached to slings
having a minimum safety factor of five. Use of No. 9 tie wire,
fiber rope, and similar makeshift lashing shall be prohibited.
(2) Taglines shall be used in moving panels or other large sections
of forms by crane or hoist.
(3) All hoisting equipment, including hoisting cable used to
raise and move forms shall have a minimum safety factor incorporated
in the manufacturer's design, and the manufacturer's recommended
loading shall not be exceeded. Field-fabricated or shop-fabricated
hoisting equipment shall be designed or approved by a registered
professional engineer, incorporating a minimum safety factor of
five in its design. Panels and built-up form sections shall be
equipped with metal hoisting brackets for attachment of slings.
(4) Forms intended for use where there is a free fall of over
ten feet shall be equipped with adequate scaffolding and guardrails,
or employees working on the forms shall be protected from falls
in accordance with chapter
296-155 WAC, Part C-1 during forming and stripping operations.
(5) Vertical forms being raised or removed in sections shall
not be released until adequately braced or secured. Overhead forms
shall not be released until adequately braced or secured.
(6) Workers or others at lower levels shall be protected from
falling materials. Appropriate warning signs shall be erected
along walkways.
(7) Forms shall not be removed until the concrete is cured. The
concrete shall be adequately set in order to permit safe removal
of the forms, shoring, and bracing. Engineer's specifications
and local building codes shall be adhered to in determining the
length of time forms should remain in place following concrete
placement. In addition, tests shall be made on field-cured concrete
specimens in order to insure that concrete has obtained sufficient
strength to safely support the load prior to removal of forms.
WAC
296-155-690 Appendix to WAC 296-155-684 cast in place concrete.
General requirements for formwork.
(This Appendix is nonmandatory.)
This Appendix serves as a nonmandatory guideline to assist employers
in complying with the formwork requirements in WAC
296-155-684 (1)(a). Formwork which has been designed, fabricated,
erected, braced, supported, and maintained in accordance with
Sections 6 and 7 of the American National Standard for Construction
and Demolition Operations-Concrete and Masonry Work, ANSI A10.9-1983,
shall be deemed to be in compliance with the provision of WAC
296-155-684 (1)(a).
(1) It shall be the responsibility of the contractor to use accessories
which are designed to be compatible.
(2) The design capacity of all lifting devices and accessories
shall be known. The devices and accessories with the appropriate
capacity shall be used.
(3) Prior to pouring the panels of a tilt-up type construction
job, a set of plans or job specifications, including lifting procedures,
shall be drawn up.
(a) These plans shall be at the job site and made available
upon request.
(b) Any changes made in the rigging procedure of a tilt-up
panel or slab shall provide the same degree of safety as required
by the original plans.
(c) The plans or specifications shall contain the following
information:
(i) The type, size, and location of all lifting inserts.
(ii) The type, size, and location of all brace inserts or
fittings for guy wires in each panel and floor or support.
(iii) The size of braces or guys to be used.
(iv) The compression strength which concrete panels must
attain prior to being lifted.
(4) The following conditions shall be included in the erection
process and shall be incorporated in the design plan:
(a) Braces and all associated components of the bracing system
shall be designed to incorporate a safety factor of one and
one-half to resist any normal stresses to which they may be
subjected, including normal high wind velocity pressures for
the area.
(b) Precast concrete wall units, structural framing, and tilt-up
wall panels shall be adequately supported to prevent overturning
and to prevent collapse until permanent connections are completed.
(c) Floor braces used to secure panel sections shall be placed
at an angle of not less than forty-five degrees or more than
sixty degrees from horizontal when physically possible to install
in this manner.
(d) The bracing on all panel sections shall be installed in
such a manner as to prevent the panel from accidentally rotating.
(e) Each panel section not secured by other means shall have
a minimum of two braces. The braces shall be installed in such
a manner as to evenly distribute the load or guy wires, when
properly installed, may be used in lieu of stiff leg braces.
(f) If braces are attached to a panel or slab by bolts tightened
into inserts installed in holes drilled in concrete, the type
of inserts used and method of installation shall be such as
to develop the required strength to be maintained for the bracing
system.
(g) Inserts to be installed for lifting sections of tilt-up
precast panels shall be designed mechanically to maintain a
safety factor of three.
(h) Lifting inserts which are embedded or otherwise attached
to precast concrete members, other than the tilt-up members,
shall be capable of supporting at least four times the maximum
intended load applied or transmitted to them.
(i) The compression strength of the concrete shall be such
that when the proper type, size, and amount of inserts are installed
a minimum safety factor of two will be maintained.
(j) Lifting hardware shall be capable of supporting at least
five times the maximum intended load applied or transmitted
to the lifting hardware.
(k) Lifting bolts or other lifting devices which have been
bent, worn, or are defective shall be discarded.
(l) The upper and lower sections of telescoping type braces
shall be secured by high tensile steel pins or bolts which provide
adequate shear strength and which will positively secure against
accidental removal.
(m) Manufactured products shall not be altered in a manner
which would reduce the safe working load to less than its original
value.
(n) Inserts shall be positioned so that bolts, or lifting devices,
when inserted, will be perpendicular to the face on which they
are placed.
(5) Design of the panels and layout of the pour shall be made
in such a manner so that when picking, the top of the panel will
be away from the crane. If this is not possible, the contractor
shall consult with a representative of the department and the
crane company involved to determine the procedure to be followed
in lifting and placing in its permanent position safely. Panels
shall be lifted and handled in such a manner that they will not
strike the hoisting equipment, in case of failure.
(a) Physical stops shall be provided which will prevent the
bottom edge of a panel being set from slipping off the edge
of its supporting structure.
(b) Tilt-up panels shall not be set when there is a possibility
that wind velocity would create a hazardous condition.
(c) A qualified signalperson shall be designated and shall
consult with the crane operator on lifting procedures prior
to making the pick. The signalperson shall be located in such
a position during the pick of the panel that they can observe
both the crane operator and the employees working in the immediate
area.
(d) During the lifting process, workers shall keep clear of
the under side of the panel.
(e) Persons not involved in the lifting process shall be kept
clear of the hazardous area near where panels are being raised,
moved or placed.
(f) If braces must be removed temporarily during construction,
other effective means shall be provided to safely support the
panel during the interim period.
(g) Each panel shall be properly braced or otherwise secured
prior to removal of the hoisting equipment.
(h) Short panels or sections not otherwise supported by floor,
footings, columns or other structure, shall be properly shored.
WAC
296-155-694 Requirements for lift-slab construction operations.
(1) Lift-slab operations shall be designed and planned by a registered
professional engineer who has experience in lift-slab construction.
Such plans and designs shall be implemented by the employer and
shall include detailed instructions and sketches indicating the
prescribed method of erection. These plans and designs shall also
include provisions for ensuring lateral stability of the building/structure
during construction.
(2) Jacks/lifting units shall be marked to indicate their rated
capacity as established by the manufacturer.
(3) Jacks/lifting units shall not be loaded beyond their rated
capacity as established by the manufacturer.
(4) Jacking equipment shall be capable of supporting at least
two and one-half times the load being lifted during jacking operations
and the equipment shall not be overloaded. For the purpose of
this provision, jacking equipment includes any load bearing component
which is used to carry out the lifting operation(s). Such equipment
includes, but is not limited to, the following: Threaded rods,
lifting attachments, lifting nuts, hook-up collars, T-caps, shearheads,
columns, and footings.
(5) Jacks/lifting units shall be designed and installed so that
they will neither lift nor continue to lift when they are loaded
in excess of their rated capacity.
(6) Jacks/lifting units shall have a safety device installed
which will cause the jacks/lifting units to support the load in
any position in the event any jack/lifting unit malfunctions or
losses [loses] its lifting ability.
(7) Jacking operations shall be synchronized in such a manner
to ensure even and uniform lifting of the slab. During lifting,
all points at which the slab is supported shall be kept within
1/2 inch of that needed to maintain the slab in a level position.
(8) If leveling is automatically controlled, a device shall be
installed that will stop the operation when the 1/2 inch tolerance
set forth in subsection (7) of this section is exceeded or where
there is a malfunction in the jacking (lifting) system.
(9) If leveling is maintained by manual controls, such controls
shall be located in a central location and attended by a competent
person while lifting is in progress. In addition to meeting the
definition in WAC
296-155-012(4), the competent person must be experienced in
the lifting operation and with the lifting equipment being used.
(10) The maximum number of manually controlled jacks/lifting
units on one slab shall be limited to a number that will permit
the operator to maintain the slab level within specified tolerances
of subsection (7) of this section, but in no case shall that number
exceed 14.
(11) No employee, except those essential to the jacking operation,
shall be permitted in the building/structure while any jacking
operation is taking place unless the building/structure has been
reinforced sufficiently to ensure its integrity during erection.
The phrase “reinforced sufficiently to ensure its integrity”
used in this subsection means that a registered professional engineer,
independent of the engineer who designed and planned the lifting
operation, has determined from the plans that if there is a loss
of support at any jack location, that loss will be confined to
that location and the structure as a whole will remain stable.
(a) Under no circumstances, shall any employee who is not essential
to the jacking operation be permitted immediately beneath a
slab while it is being lifted.
(b) For the purpose of subsection (11) of this section, a jacking
operation begins when a slab or group of slabs is lifted and
ends when such slabs are secured (with either temporary connections
or permanent connections).
(c) Employers who comply with Appendix A to WAC
296-155-694 shall be considered to be in compliance with
the provisions of subsections (11) through (11)(c) of this section.
(12) When making temporary connections to support slabs, wedges
shall be secured by tack welding, or an equivalent method of securing
the wedges to prevent them from falling out of position. Lifting
rods may not be released until the wedges at that column have
been secured.
(13) All welding on temporary and permanent connections shall
be performed by a certified welder, familiar with the welding
requirements specified in the plans and specifications for the
lift-slab operation.
(14) Load transfer from jack/lifting units to building columns
shall not be executed unit the welds on the column shear plates
(weld blocks) are cooled to air temperature.
(15) Jacks/lifting units shall be positively secured to building
columns so that they do not become dislodged or dislocated.
(16) Equipment shall be designed and installed so that the lifting
rods cannot slip out of position or the employer shall institute
other measures, such as the use of locking or blocking devices,
which will provide positive connection between the lifting rods
and attachments and will prevent components from disengaging during
lifting operations.
In WAC
296-155-694(11), WISHA requires employees to be removed from
the building/structure during jacking operations unless an independent
registered professional engineer, other than the engineer who
designed and planned the lifting operation, has determined that
the building/structure has been sufficiently reinforced to insure
the integrity of the building/structure. One method to comply
with this provision is for the employer to ensure that continuous
bottom steel is provided in every slab and in both directions
through every wall or column head area. (Column head area means
the distance between lines that are one and one half times the
thickness of the slab or drop panel. These lines are located outside
opposite faces of the outer edges of the shearhead sections-See
Figure 1.) The amount of bottom steel shall be established by
assuming loss of support at a given lifting jack and then determining
the steel necessary to carry, by catenary action over the span
between surrounding supports, the slab service dead load plus
any service dead and live loads likely to be acting on the slab
during jacking. In addition, the surrounding supports must be
capable of resisting any additional load transferred to them as
a result of the loss of support at the lifting jack considered.
(a) Deadheads used in post tensioning of tendons shall be the
type that will increase the grip on the cable as the tension
is increased.
(b) Proper means and equipment shall be used to prevent the
over-tensioning of the tendons.
(c) Only qualified workers shall perform this type work.
(2) Prestressed and poststressed concrete operations.
(a) Anchor fitting. In utilizing anchor fittings for tensioned
strands, the recommendations and instructions of the supplier
concerning installation, maintenance, and replacement shall
be followed.
(b) Tools and strand vices shall be kept clean and in good
repair.
(c) Safety factor.
(i) Expendable strand deflection devices used to pretension
concrete members shall have a minimum safety factor of two.
(ii) Reusable strand deflection devices shall have a minimum
safety factor of three.
(d) Jacking operations.
(i) During jacking operations of any tensioning element or
group of tensioning elements, the anchors shall be kept turned
up close to the anchorplate.
(ii) No one shall be permitted to stand in line or directly
over the jacking equipment during tensioning operations.
(iii) Employees shall not stand behind the jack during tensioning
operations.
(e) Jacking and pulling equipment. Pulling headers, bolts,
and hydraulic rams shall be frequently inspected for indication
of fatigue, and the threads on bolts and nuts inspected for
diminishing cross section.
(f) Storage. Stressed members shall be stored on a level base
and adequately supported during storage and transportation to
prevent tipping.
(g) Rigging.
(i) Stressed members shall be handled at pick points specifically
designated on the manufacturer's drawings.
(ii) Stressed members shall be lifted with lifting devices
recommended by the manufacturer or the engineer in charge.
(iii) No one shall be allowed under stressed members during
lifting and erection.
(1) A limited access zone shall be established whenever a masonry
wall is being constructed. The limited access zone shall conform
to the following:
(2) The limited access zone shall be established prior to the
start of construction of the wall.
(3) The limited access zone shall be equal to the height of the
wall to be constructed plus four feet, and shall run the entire
length of the wall.
(4) The limited access zone shall be established on the side
of the wall which will be unscaffolded.
(5) The limited access zone shall be restricted to entry by employees
actively engaged in constructing the wall. No other employees
shall be permitted to enter the zone.
(6) The limited access zone shall remain in place until the wall
is adequately supported to prevent overturning and to prevent
collapse unless the height of wall is over eight feet, in which
case, the limited access zone shall remain in place until the
requirements of subsection (7) of this section have been met.
(7) All masonry walls over eight feet in height shall be adequately
braced to prevent overturning and to prevent collapse unless the
wall is adequately supported so that it will not overturn or collapse.
The bracing shall remain in place until permanent supporting elements
of the structure are in place.
(8) Employees engaged in cutting or chipping shall wear suitable
eye protection in accordance with WAC
296-155-215.
(9) Masonry saws shall be constructed, guarded and operated in
accordance with WAC
296-155-367 (1) through (4).
(10) Persons charged with operation of derricks used for stone
setting shall be qualified in that type of work.
(11) Stone shall be set directly on the wall by the derrick.
(12) Breast derricks when used in setting stone shall be secured
against a slip or kick back and guyed with wire cables. Provide
hold down line to prevent derrick from falling back.
(13) Stone cutters shall wear goggles while trimming stone or
cutting holes.
(14) Pins shall be tested for security before stone is hoisted.
(15) Hoisting cables shall be protected from chafing and wearing
over corners.
(16) Mason's mortar mixers shall have a bar-type grill installed
over the mixer opening. The guard shall be installed with an automatic
disconnect switch to stop the mixer tub rotation and prevent the
mixer from starting whenever the guard is not in place.
WAC
296-155-699 Appendix A to Part O-References to Part O of
chapter 296-155 WAC. (This Appendix is nonmandatory.)
The following nonmandatory references provide information which
can be helpful in understanding and complying with the requirements
contained in Part O.
Accident Prevention Manual for Industrial Operations; Eighth
Edition; National Safety Council.
Building Code Requirements for Reinforced Concrete (ACI 318-83).
Formwork for Concrete (ACI SP-4).
Recommended Practice for Concrete Formwork (ACI 347-78).
Safety Requirements for Concrete and Masonry Work (ANSI A10.9-1983).
Standard Test Method for Compressive Strength of Cylindrical
Concrete Specimens
(ASTM C39-86).
Standard Test Method for Making and Curing Concrete Test
Specimens in the Field
(ASTM C31-85).
Standard Test Method for Penetration Resistance of Hardened
Concrete (ASTM C803-82).
Standard Test Method for Compressive Strength of Concrete
Cylinders Cast In-Place in Cylindrical Molds (ASTM C873-85).
Standard Method for Developing Early Age Compressive Test
Values and Projecting Later Age Strengths (ASTM C918-80).
For
printing