1926.705(a) 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.
1926.705(b) Jacks/lifting units shall be marked to indicate their rated capacity as established by the
manufacturer.
1926.705(c) Jacks/lifting units shall not be loaded beyond their rated capacity as established by the
manufacturer.
1926.705(d) 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.
..1926.705(e)
1926.705(e) 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.
1926.705(f) 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 jacklifting unit malfunctions or loses its lifting ability.
1926.705(g) 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.
1926.705(h) If leveling is automatically controlled, a device shall be installed that will stop the operation when
the 1/2 inch tolerance set forth in paragraph (g) of this section is exceeded or where there is a malfunction in the jacking (lifting)
system.
1926.705(i) If leveling is maintained by manual controls, such controls shall be located in a central location and
attended by a competent person whole lifting is in progress. In addition to meeting the definition in 1926.32(f), the competent person must be
experienced in the lifting operation and with the lifting equipment being used.
..1926.705(j)
1926.705(j) The maximum number of annually 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 paragraph (g) of this section, but in no case shall that
number exceed 14.
1926.705(k)
1926.705(k)(1) 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 paragraph 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.
1926.705(k)(2) 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.
1926.705(k)(3) For the purpose of paragraph (k) 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).
1926.705(k)(4) Employers who comply with appendix A to 1926.705 shall be considered to be in compliance with the
provisions of paragraphs (k)(1) through (k)(3) of this section.
..1926.705(l)
1926.705(l) 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.
1926.705(m) 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.
1926.705(n) Load transfer from jacks/lifting units to building columns shall not be executed until the welds on the
column shear plates (weld blocks) are cooled to air temperature.
1926.705(o) Jacks/lifting units shall be positively secured to building columns so that they do not become
dislodged or dislocated.
1926.705(p) 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.
[55 FR 42328, Oct. 18, 1990]
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