MIL-HDBK-1038
h)
Cab operated cranes are required to be equipped with "deadman"
controls; or alternatively, with a seat for a back-up operator.
i)
Components and assemblies of cantilever, gantry, and semi-gantry
cranes that correspond to those described above, must comply with those
requirements.
j)
Mobile cranes require no modification from their standard commercial
configuration, except that wedge sockets are prohibited for ordnance/explosives
handling. However, since they are variably rated and may need to be set on
unprepared surfaces, local policies and procedures must be followed to ensure safe
operation.
6.6
Longshoring Service. All variably rated cranes engaged in longshoring
service (loading and off-loading ships) are required to be equipped with load-
moment indicating devices (LMIs). (This requirement applies to each variably
rated hoist on a crane, and to each hoist of straight-line rated cranes which is
variably rated near its extreme reach.) The available choices of LMIs include
those with a continuous visual display of the percentage of rated capacity for the
lifted load at a particular radius as the load is maneuvered, a simple alarm (in
the form of a light or buzzer) to warn the operator that the stability limit has
been reached, or an automatic stop of the destabilizing outward or rotate motion.
Hoists on straight-line rated cranes require only a load indicating device (LID)
for longshoring service, since their operation is not restricted by the radius or
rotational position of the load hook. As in the case of LMIs, there are several
types of LIDs available. OSHA Regulation 1917.46, Load Indicating Devices,
contains requirements for such devices in longshoring service.
LMIs and LIDs are not intended to weigh loads by lifting them; their
function is only to verify the weight of the loads after the weights have been
closely estimated by other means. Paragraph 4.5.29 provides a description of the
available types of LMIs and LIDs. NCC policy is to require LMIs or LIDs, as
appropriate, on all new cranes, including those that may at some future date be
placed into longshoring service.
Cranes used in longshoring are required to be fitted with wind speed
indicating devices. In addition to indicating speed, NCC requires that wind
direction be indicated. The indicating device shall also alert the operator with
a visible or audible warning to a high wind condition. The warning is to be given
whenever the wind reaches the speed previously determined by the crane's designer
to require special operating procedures be followed. Operating instructions for
high wind conditions are required to be permanently posted in the operator's cab.
If the wind speed reaches the crane's shutdown speed, the crane is to be safely
moved clear of the vessel and secured.
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