Manual of Preventive Medicine, Chapter 6, Water Supply Afloat Flashcards
___ is responsible for the chloride and hydrogen ion testing of the ship’s P/W
Engineering officer
___ shall ensure minimum halogen residuals are maintained in a P/W tank before placing the tank on-line to the P/W distribution system
Engineering department
Responsible for collection of sample for coliform bacteria testing as prescribed and halogen residuals from the distribution system
Medical Department Representative (MDR)
Avoid making water while operating in ___
Harbors or from polluted seawater
Seawater shall be assumed polluted when ships are operated in ___
Close formation
While making P/W, care must be taken not to strip fuel waste tanks or empty bilges forward of the ___
Salt-water intakes
VOCs
Volatile Organic Chemicals
Have a lower boiling point than water and which could be present in contaminated source waters
VOCs
VOCs can ___
Vaporize and mix with the water vapor during the distillation process, carrying over into the condensate chamber and distillate reservoir
___ water tends to be mineral free and can be highly corrosive to metal piping and storage tanks
Distilled
Used aboard for drinking, laundry, medical, personal hygiene, and other purposes
P/W
Direct chemical additives to P/W systems afloat should be tested/certified by the product manufacturer IAW ___
National Sanitation Foundation International Standard known as NSF/ANSI Standard 60
Indirect chemical additives to P/W systems afloat should be tested/certified by the product manufacturer IAW ___
NSF/ANSI Standard 61
Use of seawater in food service spaces including sculleries is ___
Prohibited and seawater outlets in these spaces must be removed
Exception to seawater in sculleries
Specific garbage grinders, which use seawater flush and have been approved by BUMED for use in designated sculleries
Installation of salt water flush garbage grinders precludes storage of ___ in the scullery because of concerns for ___
Clean dishware or other items
Aerosol contamination
Used aboard ships such as in fire mains, decontamination, and for marine sanitation devices flushing
Seawater
If unusual conditions require drastic restrictions in the use of P/W, the allowances should not be less than ____ to be used for drinking and cooking purposes
2 gallons per day per man
For new ship constructions, ____ of P/W supply is specified by NAVSEA for design considerations, including uses in drinking water, galley, scullery, personal hygiene, and laundry
50 gallons per day per man
A ___ shall be completed prior to the initial transfer of water
FAC, chloramines, or TBR
If water taken onboard does not have the required halogen residual, the ship must ___, or ____
Boost halogen residual
Shore facility boost halogen residual in source water
When P/W from the transferring source contains the proper halogen residual ___
No further treatment is necessary
P/W connections between shore and ships must be made or supervised by ___
Authorized shore station personnel
In the event of no shore personnel are available to make or supervise the connection of P/W between ship and shore ____
Properly trained ship personnel will complete this responsibility
The individual making the P/W connection shall ensure hoses are not connected to a ____
Non-potable water system
Engineering will notify the ___ prior to making P/W hose connections
MDR
The ___ shall determine if the correct halogen residual is present in the source water and if it is not, they must notify the ___
MDR
Engineering Department Representative
P/W hoses shall not be submerged in ___
Harbor water
P/W may be taken from U.S. Military sources including establishments under the cognizance of the ___
British Royal Navy
Canadian Forces
Royal Australian Navy
OCONUS water source information may be obtained from ____
U.S. military representatives ashore
Navy Environmental Preventive Medicine Units
Bottled water must be obtained from ___
DoD approved sources
All water supplied by public or private systems not listed should be considered ___
Of doubtful quality
When doubt exists of the quality of the water ___
The MDR or responsible officer must investigate the source and examine the water as thoroughly as possible, and then advise the CO relative to necessary procedures, safeguards, and disinfection
P/W hoses shall not be used for ___
Any other purpose
P/W hoses must be ___
Properly labeled, stored, and protected from sources of contamination
Shipboard P/W risers shall be at least __ off the deck and turned ___, except when the risers are located ___
18”
Down
Within the ship
P/W riser must be properly labeled and fitted with ___
A cap and keeper chain
P/W riser valve or valve handles must be properly ___
Color coded
Riser hose connections shall be ___ prior to connection
Disinfected
P/W tank sounding tubes will be equipped with ___
Screw caps attached to keeper chains
P/W tank sounding tubes screw caps will be ___
Secured with a lock
On those ships equipped with sounding rods, the rod should ___
Remain in the tube at all times
P/W sounding tapes must be ___ prior to each use and shall ___
Sanitized
Only be used for P/W tank volume measurements
Disinfect connections using ___
A solution of 100-ppm FAC
Distillation plants have three general types, depending on ___
The source of the heat used to evaporate seawater
Three types of distillation plants
Steam distilling plants
Waste heat distilling plants
Vapor compression type distilling plants
Steam distilling plants are subdivided into two groups
Submerged type
Flash type
Steam distilling plant subdivisions differ mainly in ___
The heating elements and evaporator shell
___ distilling plants are submerged in the tube type and use heat derived from the diesel engine jacket water
Waste heat
___ distilling plants require primarily only electrical energy for operations
Vapor compression type
RO consists of a pre-filtration section that typically includes ___
A course strainer
Centrifugal separator
Cartridge filters that remove suspended particles as small as 1 micron in some cases
Typically ___ of the water in the RO permeates though the membrane to become fresh water
20 - 25%
RO is not solely relied upon for accomplishing ___ in single pass RO
Pathogen removal
In ___ RO plants additional disinfection requirement is waived
Triple pass
Single pass RO purity ranges from ___
350 - 500 ppm TDS
Distilled water purity ranges from ___
1 - 2 ppm TDS
Triple pass RO purity can be less than ___
1.0 ppm TDS
Low TDS distilled water and multiple pass RO water can be more ___ to plumbing and storage tanks than single pass RO water
Corrosive
Water high in ___ after multiple passes through RO membranes can also be corrosive
Dissolved gasses
Although P/W production/treatment is an engineering responsibility, the ___ must be cognizant of the process to adequately provide surveillance and recommendations
MDR
The construction and location of P/W tanks should prevent ___
Contamination of the water
The ___ is subjected to maximum external pressure from water that may be heavily polluted
Ship bottom
P/W tanks should not be filled with ballast water unless ___
Absolutely necessary for the survival of the ship
When non-potable liquid is introduced into P/W tanks ____
All tanks, lines, fittings, and pumps must be disconnected, plugged, capped, and not reconnected until adequately cleaned, flushed, disinfected, and tested
The openings of P/W vents and overflow lines must be screened with ____
18-mesh or finer non-corrosive metal wire
P/W vents and overflow lines must not terminate in ____
Food service, medical, toilet, or other spaces where contamination or odors may be transmitted to the water, nor in any space where electrical or electronic equipment is located
In no instance will P/W tanks vent ___
Outside the ship
The construction and location of manholes should minimize the possibility of ___
Contamination
If a manhole is located on the side of the tank, ___ construction is acceptable
Flush-type
If a manhole is located on the top of the tank, a ___ must be provided and the manhole cover must ___
Coaming or curb rising at least 1/2” above the top of the tank
Extend to the outer edge of the curb or flange
The manhole cover must have ___
An intact gasket and a device for securing it in place
Ships using sounding rods, when not in use should ___
Remain in the sounding tube at all times
On those ships using steel tapes for sounding, the tapes must be ___
Sanitized prior to each use, stored in a sanitary manner, and used only for P/W measurements
To sanitize P/W sounding tape ___
Soak the entire tape in a solution of 100-ppm FAC solution for 2 minutes or wiping the tape with clean gauze soaked in an approved disinfectant solution
Where a common line is used to load and distribute P/W to non-potable tanks must be through an ____
Air gap or approved and appropriate backflow prevention device
Filling lines that have common piping arrangement for directing P/W from an approved source to non-potable water systems by means off valves or interchangeable pipe fittings are ___
Not acceptable
Filling connections must be ____, and secured with ____
Clearly labeled and color-coded
Screw caps attached with keeper chains
Filling connection hose valves must be at least ___ above the deck and ____ to protect it from contamination
18”
Turned down
Special attention must be given to P/W piping located in ___, particularly the piping on the ___ side of the P/W pump
The bilge area
Suction side
The P/W piping in the bilge area should be ___
Hydrostatically tested
P/W piping through non-potable tanks and piping non-potable liquid through P/W tanks must have ___
The pipe surrounded by sloped self-draining pipe tunnel
Ensure adequate ___ is provided between the P/W outlet and a non-potable water system, fixture or machine
Air gap or approved backflow prevention device
All P/W pumps should be ___
Air-tight and free from cross connections
____ should never be used for priming P/W pumps or maintaining packing gland seals
Non-potable water
P/W pumps that have be dismantled for repair must be ___ prior to being returned to service
Disinfected after reassembly
The temperature setting for the hot water heaters serving habitability space showers and lavatories must be set not to exceed ____ at the water tap
120*F
Point of use P/W treatment devices such as charcoal impregnated or other filter equipment use are generally ___
Not recommended
Only ___ certified point of use devices shall be used
NSF
Why are point of use devices not recommended?
Remove trace halogen residual, and charcoal filtration devices can promote bacterial growth
In the event of a break or compromise in the P/W system, or a P/W tank is entered for any reason, all involved tanks, parts, and lines must be ___
Cleaned, flushed, and disinfected
The ___ must be notified of the break or entry and the disinfection procedure accomplished by the engineering department
MDR
For P/W piping repairs including flanged joints, only sealants and lubricants certified to ___ shall be used
NSF/ANSI Standard 61
P/W sounding tubes will be ____, and the cap will be color coded ____
Labeled with an identification plate
Dark blue
On ships using steel tapes for sounding P/W tanks, the tape handle must be ___
Color coded dark blue or identified “POTABLE WATER USE ONLY”
Valves for receiving or supplying P/W must be conspicuously designated by a warning plate bearing the inscription ____ in _____
POTABLE WATER ONLY
1/4” high letters
P/W hoses must be labeled ___ with ___ every ____ and the end couplings ____
POTABLE WATER ONLY
1” high letters
10 feet
Painted dark blue
P/W piping passing through any given space must be ___
Appropriately labeled to indicate the type of service and with an arrow indicating the direction of flow
P/W hose storage lockers must be identified and labeled ___
POTABLE WATER HOSE
When not in use P/W hoses must be ___
Coupled or capped and stored in designated lockers
P/W hose lockers must be ___
Vermin-proof, locked, and be elevated at least 18” off of the deck when located on weather decks and sponsons
___ must be posted in a conspicuous location inside the hose storage locker
Printed instructions for disinfection of P/W hoses and risers
___ is required to ensure the destruction of pathogenic organisms
Disinfection of water
___ is the usual method of guarding against contamination or accidents that may occur during the production, handling, storage, and distribution of P/W
Maintenance of halogen residual
The absence of FAC or TBR in the ship’s P/W may indicate ___
Contamination
Where certain organic substances are present, very small concentrations of combined chlorine or bromine can produce ____
Undesirable tastes or odors
Safety of water
Potability
Taste of water
Palatability
The EPA has established a maximum contaminant level for all disinfectants at ___
4 ppm
The amount of chlorine or bromine used through reaction with substances present in the water
Halogen demand
Shipboard water is disinfected by the addition of sufficient chlorine or bromine to produce not less than ___ FAC or TBR after 30 minute contact time measured at ___
0.2 ppm
The P/W tank
___ methods of treatment are preferable to chlorine batch treatment procedures
Mechanical
Chlorine is available for shipboard use as ___
Calcium hypochlorite (HTH 65-70% available chlorine), 6-oz bottle, a granular solid or sodium hypochlorite in varying strengths, as a liquid
HTH is most frequently used because of its ___
Relatively long shelf life and reduced storage requirements
HTH presents a potential personnel and fire hazard due to ___
Its corrosiveness and chemically active nature
HTH is classified as ___
Hazardous
Contact between HTH and oxidizable material may result in ___
Spontaneous combustion
HTH should be obtained in ___
6-oz containers
HTH should be stored in ___
A cool, dry, well-ventilated place with no danger of contact with oxidizable material
Calcium or sodium hypochlorite will ___ gradually with age and more rapidly when ___
Lose strength
Opened or stored in hot spaces or sunlight
