prevmed 2 test review Flashcards
define distillation
process of distilling plant forms including evaporation and condensation
what is FAC
Free Available Chlorine
Chlorine available in the form of hypochlorous acid and hypochlorite ions
which is the test to detect coliform and e. coli in potable water
**EPA approved **
colilert and colisure
harmless bacteria that live in soil, water as well as guts of animals
total coliform
fecal coliform found in the intestines in animals and humans
e coli
who is responsible for the shipboard potable water system including treatment facilities and process to assure safe drinking water is available
Design, construct, maintain
NAVSEASYSCOM
who promulgates instructions for ship to shore potable water connections and for providing potable water from approved source when ship is at a naval facility
NAVFACENGCOM
what is the CO responsibilities for potable water surveillance
water sanitation bill
procedures for receipt, transfer, treatment, storage, distribution and surveillance
how many gallons per man per day for new ship construction
50 gal per man per day
what are water hours per man per day
no less than 2 gal per man per day
what type of water does marine sanitation devices use
sea water
types of water distillation
steam
waste heat
vapor compression
type of distillation uses electrical energy
vapor compression
type of distillation uses diesel engine jacket water
waste heat
types of reverse osmosis (RO) and what additional testing is required per pass
single- additional disinfection (chlorination or brominating)
Triple- none. better than distilled
what standard must potable water tank coating meet
NSF and ANSI
what do vents and over flow lines do
reduce accidental contamination
how must sounding tubes be labeled
“POTABLE WATER USE ONLY”
what color coded are filling lines and specifications
dark blue
18inch from deck
turned facing downward
screw caps w/ keeper chains
potable water hose lockers must be
vermin proof
locked
18 in off deck
printed step by step instructions for disinfection of hoses and risers
how are potable water hoses marked and labeled
“POTABLE WATER ONLY” 1inch high letters every 10 feet
what color are valves or valve handles
dark blue
potable water connections between shore and ship must be made or supervised by whom
authorized shore station personnel or properly trained ship personnel/ engineers
what’s the minimum halogen residual requirement when water from doubtful quality
2.0ppm
why is bacteriological testing conducted
ensure fitness for human consumption
to asses adequacy of disinfection process
what the frequency of monitoring for microbiological quality
weekly
when collecting WATER samples what are the required locations #S
400 or less-=4
400-800= 8
800 or more= 12
1/4 ice machines and ships potable water tanks (25% DUMBY)
halogen testing what is tested under DPD1 and DPD 4
DPD1 -FAC and TBR
DPD 4- chloramines
what is used to measure halogen testing? accuracy %?
color comparator =or - 10%
portable spectophotometer= + or - 2%
what are the sources of contamination
cross connections leaks in bulk heads leaks non-potable piping Improper disposal of chemical liquid potable water hoses used for non potable liquids excessive storage in water tanks contaminated raw water source inadequate disinfection transfer of water from shore barges and many more
what is the least desirable method of water disinfection and which is the disinfection of choice
least= Manual chloride disinfection (batch method) choice= calcium hypochlorite (HTH)
what are the halogen residual minimum measurements from an approved source? unapproved source?
Approved= 0.2ppm FAC/TBR after 30 min
unapproved= 2.0 ppm FAC/TBR after 30 min
during chlorine dose calculation one ounce of HTH per 5000 gallons of water equals how many ppm FAC
1.0ppm FAC
if brominator can not achieve a TBR of 2.0 ppm water must be chlorinated by what method
batch method
explain disinfection method 1
fill tank to over flow level add chlorine to achieve 10ppm FAC hold for 24 hours drain tank refill tank w/ potable water bacteriological test neg use water
explain disinfection method 2
spray applied directly 200ppm FAC to all tank surfaces
flush pipes with 10ppm FAC
disinfected surface should remain in contact w/ chlorine solution for
30 minutes
refill tank w/ potable water
bacteriological test
neg use water
describe “method 3” of disinfecting potable water tanks
FILL 5% TANK VOLUME W/ 50PPM FAC SOLUTION
hold solution for 6 hours
add potable water to chlorine solution to fill tank; hold for 24 hours
drain tank
refill tank w/ potable water w/ required halogen residual level
bacteriological test
negative use water
what are the 2 methods for controlling and identifying the source of taste and odor issues if problem cannot be identified first?
chlorination and steam methods
describe chlorination method for taste/odor issues
chlorinate to 5ppm FAC
distribute @ 2 ppm FAC
describe the steam method for taste/odor issues
requires NAVSEASYSCOM approval
boil sample water for 1 minute to ensure proper effect
if resolved then steam may be feasible
not resolved then steam wont work
What is the strength % of HTH? How many ounce bottles? Where and how is it stored?
65-70%
6 ounce bottles
Metal box w/ 3 ¼ inch holes drilled in box to release chlorine
No more than 48 bottles
Labeled “Hazardous material, calcium hypochlorite”
Water sanitation bill should consist of what?
Connection procedures (ship to shore) (ship to ship)
Potable water hoses
Storage tanks
Disinfection procedures
Halogen residual, bacteriological , temperature, pH, and salinity testing
Disinfection of tanks and distribution system
Distribution system
Records
How long with the MDR maintain a potable water log?
2 years
MDR responsibilities for prevention of wastewater hazards
conduct visual inspections of marine sanitation devices quarterly
indoctrination and periodic training concerning potential health hazards associated with human waste
on-site advice when requested in event of major sewages leaks or spills
must be present during clean-ups and disinfection operations involving food service spaces, living spaces, and medical spaces
what does CHT stand for
collection hold and transfer system
what are the there modes of CHT systems
restricted waters
at sea
in port
what is the most common marine sanitation device?
Type II B marine sanitation device
what poses the greatest danger to ship and personnel regarding CHT and wastewater
Hydrogen Sulfate (H2S) which can become explosive if not aerated
must be aerated when held in tanks larger than 2000 gallons must
be aerated
define EEBD. how long are EEBDs good for and where should they be kept
Emergency Escape breathing Device
10 minutes
pump rooms must have them
what are gases associated with CHT
hydrogen sulfide - rotten egg smell
methane
ammonia
carbon dioxide
requirements that must be strictly adhered to for CHT workers to prevent transmission of disease
personal hygiene and PPE
medical, food service, and berthing spaces must be disinfected with what EPA approved disinfectants? what are the 2 types?
Germicides such as phenolic type and iodine type
color coding for ships internal? external CHT systems?
Internal valve handles and operating levers: gold
external: deck discharge same as surrounding structure
Waste water disposal procedures:
- within US waters is?
- sewage and gray water at sea?
- in port?
- restricted waters?
- prohibited within 3 nautical miles
- diverted and discharged overboard
- CHT and discarded using SHIP WASTE OFF LOAD BARGES (SWOB)
- sewage in CHT, gray water discarded overboard via diverter valves
procedures for all ship tp shore transfer facilities of CHT is under what instruction?
NAVFAC PUB 340
engineer officer responsibilities for ground forces water
provides sufficient potable water quantities
selection water sources
construct, operate and maintain
MDR responsibilities for ground forces water
advice CO
assist Engineer Officer
test Halogen and Bacteriological levels
what are three influences on water choice
quality
quantity
accessibility
lakes , streams , river , pond, sea ocean
more accessible. Quality may be problem. More contaminated that other sources. Capable of supplying adequate quantities. Screen intakes carefully
types of surface water
wells and springs
usually less contaminated than surface water. Difficult to determine quantities available. Located at least 30 yards upgradient from known contamination
ground water sources