Disinfection

Question 1

What processes purpose is to prevent outbreak of waterborne diseases?

Answer 1

Disinfection

Question 2

What disinfectant consists of a yellow gas, which is 2.5 times heavier than air

Answer 2

Chlorine Gas

Question 3

What byproducts are made when using Chlorine Gas as a disinfectant?

Answer 3

Hypochlorous Acid & hydrochloric Acid

Question 4

Chlorine with disinfecting power left over, which safeguards against further Chlorine Demand.

Answer 4

Free Chlorine Residual

Question 5

This type of residual has not reacted to anything in the water.

Answer 5

Free Chlorine Residual

Question 6

This type of disinfectant comes in liquid form and has a chlorine strength of 12.5%.

Answer 6

Sodium Hypochlorite

Question 7

______ is used to eliminate pathogens in drinking water.

Answer 7

Disinfection

Question 8

What situations require disinfection.

Answer 8

Laying new water mains, repair and maintenance, and sanitizing storage tanks

Question 9

This disinfectant lowers the Ph of water when introduced.

Answer 9

Chlorine Gas

Question 10

Chlorine that reacts with organic & inorganic material will determine _______.

Answer 10

Chlorine Demand

Question 11

What are the two parts of Total Chlorine Residual.

Answer 11

Free Chlorine Residual & Combined Chlorine Residual

Question 12

This type of residual has combined itself with something in the water.

Answer 12

Combined Chlorine Residual

Question 13

House hold Clorox is a type of this disinfectant.

Answer 13

Sodium Hypochlorite

Question 14

This disinfectant comes in tablet or granular form, and has a chlorine strength of 65%.

Answer 14

Calcium Hypochlorite

Question 15

What is it called when you have added chlorine to water until the chlorine demand has been met.

Answer 15

Breakpoint

Question 16

Natural Organic Material + Chlorine Disinfectant = _________.

Answer 16

Disinfectant Byproduct

Question 17

What method is used to take chlorine residual samples.

Answer 17

DPD Method

Question 18

The maximum Chlorine residual requirement is.

Answer 18

4 mg/L

Question 19

The minimum Chlorine residual requirement is.

Answer 19

0.2 mg/L

Question 20

These two disinfectants raise the Ph level of water when used.

Answer 20

Sodium Hypochlorite & Calcium Hypochlorite

Question 21

This disinfectant is also known as High Test Hypochlorite (HTH).

Answer 21

Calcium Hypochlorite

Question 22

What happens when you add chlorine after breakpoint has been met.

Answer 22

Free Chlorine Residual rises

Question 23

What Happens when you don’t store Calcium Hypochlorite in a cool and dry location.

Answer 23

Moisture will breakdown the disinfectant, and excess heat will cause Chlorine gas to form which may create an explosive hazard

Question 24

What are two types of disinfectant byproducts when using Chloromine.

Answer 24

Trihalomethane & haloacetic Acid

Question 25

What are 5 factors that affect chlorine effectiveness

Answer 25

Chlorine Residual Concentration, Contact Time, Ph Level, Temperature, and Turbidity

Question 26

When Chlorine is combined with ammonia what does it make.

Answer 26

Chloromine

Question 27

What are 3 types of Chloromine.

Answer 27

Monochloromine, Dichloromine, and Trichloramine

Question 28

What are the three major types of disinfectants.

Answer 28

Chlorine, Chloromine, and Ozone

Question 29

What are the advantages of using Ozone as a disinfectant.

Answer 29

Generated on-site, contact time is short, and it is good at destroying viruses

Question 30

What are some disadvantages of using Ozone as a disinfectant.

Answer 30

Ozone is an unstable gas and highly corosive

Question 31

What happens when bromide is present while using Ozone as a disinfectant.

Answer 31

Ozone can react and make bromate