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 CHAPTER 13.
COLD WEATHER CLIMATES
13.1 INTRODUCTION. As stated in Chapter 1, the procedures discussed in the
preceding chapters were developed as part of an extensive study program con-
ducted in San Diego, California. As such, the procedures were not validated
for cold weather environments. The information presented in this chapter
was derived from cold weather hose handling operations conducted in Norfolk,
Virginia and New London, Connecticut during the 1977-78 and 1978-79 winter
seasons. Direct observation of the disconnecting of frozen sewage hoses
demonstrated clearly that all reasonable precautions must be taken to pre-
vent hoses from freezing. A frozen hose, especially one containing substan-
tial quantities of sewage, is stiff, heavy, and extremely difficult to
handle, and generally requires more than the usual two-man shore hose han-
dling team.
In addition to added safety and sanitary handling requirements, the
potential for material damage to the hose, ship connection fitting, and/or
shore connection station is increased. However, for reasons presented below
(see 13.2), no single hose handling procedure applicable to all cold weather
environments can be recommended at this time. The remainder of this chapter
discusses various techniques or methods that should be considered for use in
a particular situation or at a particular activity. The final selection of
methods must be made by knowledgeable, experienced, on-site personnel.
13.2 COLD WEATHER EVALUATION. The wide disparity in climatic conditions,
ranging from extended periods of temperatures well below freezing to periods
as short as a few hours with temperatures slightly below freezing, imposes a
disparity in hose freeze-prevention requirements. Additionally, the period
of time a hose hookup is required must be considered. For example, ships
such as tenders usually are in port for months at a time, requiring continu-
ous hookup of sewage hoses. Conversely, some ships require only overnight
hose service or service for a few days. No passive freeze-prevention-method
(one requiring no additional attention or action after its installation) has
been identified to provide protection in all cold weather conditions and/or
periods of use. Similarly, no active freeze-prevention method (one requiring
periodic personnel attention or steam, electric, or other services) can be
specified, as these services are not always readily available.
13.3 HOSE HANDLING/CONNECTION/DISCONNECTION. Beginning at approximately
4 C (40 F) hose flexibility decreases noticeably as temperature
decreases. When the hoses are cold, they resist changes in their physical
shape and, unless restrained, tend to return to their original configura-
tions, for example, coiled before a ship connection or laid out after a
disconnection. This does not hamper handling operations seriously when a
powered hose reel is used, but can be a problem during manual operations.
Handling by more than two persons and restraint of the leading end of the
hose may be required. Storage of coiled hose in a heated area prior to a
ship connection, and transportation in an enclosed, heated truck are recom-
mended. Adequate flushing of an installed hose immediately prior to discon-
nection not only will provide the required disinfection} but also will serve
to raise the hose temperature, and thereby alleviate handling difficulties.
13-1
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