PMT 108 PRINCIPLES OF WATER
EXAM QUESTIONS WITH
CORRECT ANSWERS
Microbiological Quality - Answer- Presence of microorganisms indicated the potential for
disease transmission (coliform testing)
Marginal chlorination - Answer- Initial chlorine demand has been satisfied but some
oxidizable substances remain
Springs - Answer- A natural source of water formed when water from an aquifer
percolates up to the ground surface.
Wells - Answer- Clear, Cool, Colorless & Uniform (CCCU)
Better microbiological quality & less organic material. Highly mineralized and
categorized by construction method.
Super Chlorination - Answer- Application fo chlorine in greater concentrations then are
needed to afford acceptable bactericides efficiency.
Break point chlorination - Answer- Applied to produce a chlorine residual composed of
predominantly FAC with little or no combine chlorine
Steps in solving a waterborne disease outbreak - Answer- Prepare for field work
Establish its existence
Verify diagnosis
Define and identify cases
Describe and orient the data in terms of time, place and person
Develop hypothesis
Evaluate hypotheses
Refine hypotheses and carry out studies
Implement control and prevention
Communicate findings
unrefrigerated samples - Answer- 1 hour
Refrigerated samples - Answer- 6 hours
No more than 30 hours - Answer- Should elapse before analysis of a sample
, If more than 30 but less than 48 hours pass... - Answer- The lab may run the sample
with disclaimers that the data is possibly invalid
More than 48 hours have elapsed - Answer- Labs must refuse samples
DPD tablet #1 - Answer- FAC (free available chlorine)
DPD tablet #4 - Answer- TAC (total available chlorine)
After use of the LaMotte Kit... - Answer- Remove trash
Rinse and clean all tubes, allow them to dry. Use a brush and detergent if necessary.
Refill DPD tablets
Leave kit open to air dry
Colilert results - Answer- Definitive at 24-28 hours
Colilert Reminders - Answer- Keep away from light, stored between 2-30 deg C,
dry/free-flowing/white to off white in color,
when incubation exceeds 28 hrs only negative samples are valid,
shelf life @ 12 months from manufacturing date.
Disposal of negative samples - Answer- Pour down the sink and flush with water.
Rinse containers and throw away.
Positive sample disposal - Answer- Open the sample and fill with liquid bleach to the top
of the vessel.
Let's stand 20 minutes.
Pour down the sink and flush with water.
Throw away vessel.
Alternate disposable of a positive sample - Answer- Autoclave vessels for 20 minutes at
121°C in a bio bag and then discard properly.
U.S. Environmental Protection Agency (EPA) - Answer- federal agency tasked with
setting and enforcing national pollution standards
Prev Med authority - Answer- Advisory role, provides public health related consultant
assistance as needed.
Factors to be considered (water source selection) - Answer- Sources of pollution
Hydrological studies
Proposed intake location
Calcium hypochlorite - Answer- Widely used procedure for the routine disinfection of
water
EXAM QUESTIONS WITH
CORRECT ANSWERS
Microbiological Quality - Answer- Presence of microorganisms indicated the potential for
disease transmission (coliform testing)
Marginal chlorination - Answer- Initial chlorine demand has been satisfied but some
oxidizable substances remain
Springs - Answer- A natural source of water formed when water from an aquifer
percolates up to the ground surface.
Wells - Answer- Clear, Cool, Colorless & Uniform (CCCU)
Better microbiological quality & less organic material. Highly mineralized and
categorized by construction method.
Super Chlorination - Answer- Application fo chlorine in greater concentrations then are
needed to afford acceptable bactericides efficiency.
Break point chlorination - Answer- Applied to produce a chlorine residual composed of
predominantly FAC with little or no combine chlorine
Steps in solving a waterborne disease outbreak - Answer- Prepare for field work
Establish its existence
Verify diagnosis
Define and identify cases
Describe and orient the data in terms of time, place and person
Develop hypothesis
Evaluate hypotheses
Refine hypotheses and carry out studies
Implement control and prevention
Communicate findings
unrefrigerated samples - Answer- 1 hour
Refrigerated samples - Answer- 6 hours
No more than 30 hours - Answer- Should elapse before analysis of a sample
, If more than 30 but less than 48 hours pass... - Answer- The lab may run the sample
with disclaimers that the data is possibly invalid
More than 48 hours have elapsed - Answer- Labs must refuse samples
DPD tablet #1 - Answer- FAC (free available chlorine)
DPD tablet #4 - Answer- TAC (total available chlorine)
After use of the LaMotte Kit... - Answer- Remove trash
Rinse and clean all tubes, allow them to dry. Use a brush and detergent if necessary.
Refill DPD tablets
Leave kit open to air dry
Colilert results - Answer- Definitive at 24-28 hours
Colilert Reminders - Answer- Keep away from light, stored between 2-30 deg C,
dry/free-flowing/white to off white in color,
when incubation exceeds 28 hrs only negative samples are valid,
shelf life @ 12 months from manufacturing date.
Disposal of negative samples - Answer- Pour down the sink and flush with water.
Rinse containers and throw away.
Positive sample disposal - Answer- Open the sample and fill with liquid bleach to the top
of the vessel.
Let's stand 20 minutes.
Pour down the sink and flush with water.
Throw away vessel.
Alternate disposable of a positive sample - Answer- Autoclave vessels for 20 minutes at
121°C in a bio bag and then discard properly.
U.S. Environmental Protection Agency (EPA) - Answer- federal agency tasked with
setting and enforcing national pollution standards
Prev Med authority - Answer- Advisory role, provides public health related consultant
assistance as needed.
Factors to be considered (water source selection) - Answer- Sources of pollution
Hydrological studies
Proposed intake location
Calcium hypochlorite - Answer- Widely used procedure for the routine disinfection of
water
