Hotel Service Unit 14 Fresh water Flashcards

Hotel Service Unit 14 Fresh water

What method can be used to ensure the pH of domestic water remains slightly alkaline?

B) Adding hydrated lime

Which micro-organism in water can lead to algal blooms and affect water clarity?

B) Algae

What is the primary treatment required for fresh water taken on board from ashore?

B) Adding chlorine or other disinfectants to ensure it is free from bacteria

Which of the following is a desired property of domestic water for safe use?

B) Neutral or slightly alkaline pH to prevent corrosion

How does a Silver Ion Sterilizer introduce ions into the water?

B) By using silver electrodes that release ions when an electric current is applied

How is microbial content commonly controlled in domestic water?

B) Through chlorination or ultraviolet (UV) sterilization

Which alternative method can be used to sterilize water on board without adding chemicals?

B) Using ultraviolet (UV) light

Why is it important to inspect a tank before reintroducing it to service?

B) To verify it is structurally sound and free from any signs of corrosion or damage

Which other method is commonly used to produce fresh water on vessels?

B) Reverse osmosis filtration

Which micro-organism is most likely to cause diseases such as dysentery and cholera if present in drinking water?

B) Bacteria

Which of the following is a common type of micro-organism found in untreated water?

D) All of the above

During the superchlorination process, what is the typical chlorine concentration required?

B) 20–50 mg/L

What is one method commonly used on board ships to kill bacteria in potable water?

B) Adding chlorine or chlorine-based compounds

How long should the water system be left with superchlorination levels to ensure disinfection?

C) 12–24 hours

What causes copper staining in a fresh water system?

B) Low pH or acidic water causing copper to dissolve from pipes

What is an advantage of using a Silver Ion Sterilizer over chlorination?

B) It does not alter the taste or odor of water

What is the primary purpose of superchlorinating a fresh water system?

B) To eliminate bacteria, pathogens, and biofilm buildup

What is the primary purpose of a Silver Ion Sterilizer in water treatment?

B) To kill bacteria and other harmful micro-organisms

What should be done after completing the superchlorination process?

A) Flush the system with fresh water until chlorine levels are below 0.5 mg/L

Why is chlorination often used when taking on fresh water from ashore?

B) To kill any bacteria or pathogens that might be present

After cleaning the tank, what should be done next before putting it back into service?

A) Rinse the tank with treated water to remove residual disinfectants

What other benefit does adding hydrated lime to water provide?

B) Improves the taste by adding minerals

Why is it important for domestic water to be free from turbidity?

B) Clear water without turbidity is less likely to harbor pathogens and is aesthetically pleasing

Which process is often used to remove turbidity from domestic water?

C) Sedimentation and filtration

Why must domestic water have low microbial content?

B) High microbial content increases the risk of disease

What additional method can help reduce copper staining if adjusting pH is insufficient

A) Using water filters with copper-absorbing materials

What is the role of silver ions in sterilizing water?

B) They kill micro-organisms by disrupting their cell walls and preventing reproduction

Which pH range helps prevent copper staining in fresh water systems?

C) 7–8

What is a common method to prevent copper staining in a water system?

B) Using alkaline additives to raise pH and reduce water acidity

Why is hydrated lime added to fresh water produced on board an ocean-going vessel?

B) To adjust the pH level, making the water slightly alkaline and reducing corrosion

What is the first step before bringing a fresh water tank back into service?

B) Clean and disinfect the tank
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