Lead-containing materials, such as putty and white lead, are hazardous to
personnel and shall not be used for piping repairs or for buttering -up flanged
or threaded joints.
Repairs. Piping repairs and buttering- up of flanged and threaded joints shall be performed with a
silicone-based compound (e.g. , silicone adhesive, National Stock Number (NSN) 8040001182695).
a. General. Distillers (evaporators) produce fresh water from seawater for use in boiler make- up,
electronic cooling, and potable water. Reverse Osmosis (RO) desalinators produce fresh water from
seawater for potable water and, when combined with a second RO stage or a demineralizer, produce
higher-grade water for boiler make-up and electronic cooling. The product water from a distiller is
called "distillate," whereas the product water from an RO unit is referred to as "permeate." Only afte r
the distillate/permeate ("product water") is treated in the brominator, should it be referred to as
(1) Distillate is very pure. It contains less than 2.3 ppm chloride ions, which is equivalent to
4.6 ppm Total Dissolved Solids (TDS). A concentration of 4.6 ppm TDS yields a conductivity
of 9.2 micromhos/cm.
(2) Permeate from a single stage RO unit ranges in purity from 350 to 500 ppm TDS. The
limit for TDS in potable water is 500 ppm.
b. Distillers. Distillers (also referred to as evaporators) installed on watercraft fall into one of the
following three classes:
(1) Low Pressure Steam Distilling Plants. Examples include submerged tube, vertical basket,
and flash-type distilling units.
(2) Vapor Compression Distilling Plants. Examples include vertical tube and rising- film
(3) Heat Recovery Distilling Plants (also referred to as waste heat evaporators).
c. Polluted Water. Unless determined otherwise, water in harbors, rivers, inlets, bays, landlocked
waters, and the open sea within 12 miles of the entrance to these waterways, shall be considered to be
polluted. Other areas may be declared to be polluted as well by medical personnel. The desalination
of polluted harbor water/seawater for human consumption shall be avoided except in emergencies. If
distillation of polluted harbor water/seawater becomes necessary, the procedures in paragraph 12. f
shall be followed.
d. Operation in Seawater. Desalinators are designed to operate on full strength seawater in the open
ocean. Each desalinator has a salinity panel, which monitors the product water, with an associated